Citation
The role of the temporomandibular joint in mediating perception of mandibular position

Material Information

Title:
The role of the temporomandibular joint in mediating perception of mandibular position
Creator:
Riski, John Edward, 1948-
Publication Date:
Language:
English
Physical Description:
xi, 157 leaves : ill. ; 28 cm.

Subjects

Subjects / Keywords:
Anesthesia ( jstor )
Capsules ( jstor )
Diphthongs ( jstor )
Interdental consonants ( jstor )
Jaw ( jstor )
Mandible ( jstor )
Nerves ( jstor )
Teeth ( jstor )
Temporomandibular joint ( jstor )
Vowels ( jstor )
Mandible ( lcsh )
Temporomandibular joint ( lcsh )
City of Springfield ( local )
Genre:
bibliography ( marcgt )
non-fiction ( marcgt )

Notes

Thesis:
Thesis--University of Florida.
Bibliography:
Includes bibliographical references (leaves 150-156).
General Note:
Typescript.
General Note:
Vita.
Statement of Responsibility:
by John Edward Riski.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
03211557 ( OCLC )
ocm03211557
0025711256 ( ALEPH )

Downloads

This item has the following downloads:

EKP2RBVIV_J3QFRT.xml

AA00012901_00001.pdf

roleoftemporoman00risk_0139.txt

roleoftemporoman00risk_0045.txt

AA00012901_00001_0039.txt

AA00012901_00001_0151.txt

AA00012901_00001_0082.txt

AA00012901_00001_0037.txt

roleoftemporoman00risk_0085.txt

AA00012901_00001_0147.txt

AA00012901_00001_0109.txt

roleoftemporoman00risk_0136.txt

AA00012901_00001_0168.txt

AA00012901_00001_0158.txt

roleoftemporoman00risk_0023.txt

AA00012901_00001_0138.txt

AA00012901_00001_0166.txt

AA00012901_00001_0135.txt

AA00012901_00001_0115.txt

roleoftemporoman00risk_0123.txt

AA00012901_00001_0069.txt

AA00012901_00001_0153.txt

AA00012901_00001_0156.txt

roleoftemporoman00risk_0093.txt

roleoftemporoman00risk_0002.txt

roleoftemporoman00risk_0153.txt

AA00012901_00001_0055.txt

roleoftemporoman00risk_0159.txt

roleoftemporoman00risk_0079.txt

roleoftemporoman00risk_0165.txt

AA00012901_00001_0122.txt

AA00012901_00001_0013.txt

roleoftemporoman00risk_0078.txt

AA00012901_00001_0076.txt

AA00012901_00001_0012.txt

roleoftemporoman00risk_0135.txt

roleoftemporoman00risk_0150.txt

roleoftemporoman00risk_0138.txt

AA00012901_00001_0050.txt

roleoftemporoman00risk_0064.txt

AA00012901_00001_0084.txt

AA00012901_00001_0088.txt

roleoftemporoman00risk_0120.txt

AA00012901_00001_0043.txt

roleoftemporoman00risk_0038.txt

AA00012901_00001_0171.txt

roleoftemporoman00risk_0158.txt

AA00012901_00001_0077.txt

roleoftemporoman00risk_0134.txt

roleoftemporoman00risk_0089.txt

roleoftemporoman00risk_0087.txt

AA00012901_00001_0157.txt

roleoftemporoman00risk_0121.txt

AA00012901_00001_0074.txt

roleoftemporoman00risk_0067.txt

AA00012901_00001_0155.txt

roleoftemporoman00risk_0095.txt

roleoftemporoman00risk_0042.txt

roleoftemporoman00risk_0052.txt

AA00012901_00001_0007.txt

AA00012901_00001_0101.txt

AA00012901_00001_0046.txt

AA00012901_00001_0049.txt

roleoftemporoman00risk_0160.txt

AA00012901_00001_0092.txt

roleoftemporoman00risk_0055.txt

AA00012901_00001_0056.txt

AA00012901_00001_0127.txt

roleoftemporoman00risk_0074.txt

roleoftemporoman00risk_0152.txt

AA00012901_00001_0022.txt

AA00012901_00001_0126.txt

AA00012901_00001_0093.txt

roleoftemporoman00risk_0029.txt

roleoftemporoman00risk_0069.txt

roleoftemporoman00risk_0097.txt

roleoftemporoman00risk_0170.txt

roleoftemporoman00risk_0119.txt

roleoftemporoman00risk_0145.txt

AA00012901_00001_0071.txt

roleoftemporoman00risk_0054.txt

roleoftemporoman00risk_0037.txt

roleoftemporoman00risk_0018.txt

AA00012901_00001_0086.txt

roleoftemporoman00risk_0016.txt

roleoftemporoman00risk_0063.txt

AA00012901_00001_0031.txt

AA00012901_00001_0087.txt

AA00012901_00001_0035.txt

roleoftemporoman00risk_0026.txt

roleoftemporoman00risk_0028.txt

AA00012901_00001_0123.txt

AA00012901_00001_0121.txt

AA00012901_00001_0099.txt

roleoftemporoman00risk_0039.txt

AA00012901_00001_0143.txt

roleoftemporoman00risk_0146.txt

roleoftemporoman00risk_0091.txt

AA00012901_00001_0033.txt

AA00012901_00001_0075.txt

AA00012901_00001_0103.txt

roleoftemporoman00risk_0033.txt

AA00012901_00001_0170.txt

roleoftemporoman00risk_0168.txt

AA00012901_00001_0164.txt

roleoftemporoman00risk_0096.txt

roleoftemporoman00risk_0109.txt

AA00012901_00001_0065.txt

roleoftemporoman00risk_0020.txt

AA00012901_00001_0070.txt

AA00012901_00001_0116.txt

AA00012901_00001_0024.txt

AA00012901_00001_0026.txt

roleoftemporoman00risk_0131.txt

roleoftemporoman00risk_0000.txt

roleoftemporoman00risk_0102.txt

AA00012901_00001_0160.txt

roleoftemporoman00risk_0115.txt

AA00012901_00001_0034.txt

AA00012901_00001_0111.txt

AA00012901_00001_0162.txt

AA00012901_00001_0032.txt

roleoftemporoman00risk_0012.txt

AA00012901_00001_0078.txt

roleoftemporoman00risk_0032.txt

roleoftemporoman00risk_0050.txt

AA00012901_00001_0045.txt

roleoftemporoman00risk_0077.txt

AA00012901_00001_0068.txt

AA00012901_00001_0105.txt

AA00012901_00001_0117.txt

roleoftemporoman00risk_0106.txt

AA00012901_00001_0161.txt

roleoftemporoman00risk_0009.txt

AA00012901_00001_0128.txt

roleoftemporoman00risk_0118.txt

roleoftemporoman00risk_0008.txt

AA00012901_00001_0145.txt

roleoftemporoman00risk_0010.txt

AA00012901_00001_0054.txt

AA00012901_00001_0144.txt

roleoftemporoman00risk_0057.txt

roleoftemporoman00risk_0058.txt

roleoftemporoman00risk_0113.txt

AA00012901_00001_0091.txt

roleoftemporoman00risk_0117.txt

roleoftemporoman00risk_0132.txt

roleoftemporoman00risk_0105.txt

roleoftemporoman00risk_0169.txt

AA00012901_00001_0163.txt

AA00012901_00001_0132.txt

AA00012901_00001_0073.txt

roleoftemporoman00risk_0167.txt

roleoftemporoman00risk_0025.txt

AA00012901_00001_0108.txt

AA00012901_00001_0027.txt

AA00012901_00001_0059.txt

AA00012901_00001_0053.txt

AA00012901_00001_0152.txt

AA00012901_00001_0015.txt

AA00012901_00001_0104.txt

AA00012901_00001_0052.txt

AA00012901_00001_0057.txt

roleoftemporoman00risk_0162.txt

AA00012901_00001_0072.txt

roleoftemporoman00risk_0116.txt

AA00012901_00001_0058.txt

AA00012901_00001_0113.txt

roleoftemporoman00risk_0040.txt

roleoftemporoman00risk_0017.txt

roleoftemporoman00risk_0049.txt

roleoftemporoman00risk_0021.txt

roleoftemporoman00risk_0072.txt

AA00012901_00001_0134.txt

roleoftemporoman00risk_0048.txt

AA00012901_00001_0124.txt

AA00012901_00001_0019.txt

roleoftemporoman00risk_0041.txt

AA00012901_00001_0008.txt

roleoftemporoman00risk_0129.txt

roleoftemporoman00risk_0030.txt

roleoftemporoman00risk_0151.txt

roleoftemporoman00risk_0056.txt

roleoftemporoman00risk_0081.txt

AA00012901_00001_0062.txt

AA00012901_00001_0106.txt

AA00012901_00001_0131.txt

AA00012901_00001_0140.txt

AA00012901_00001_0118.txt

AA00012901_00001_0085.txt

roleoftemporoman00risk_0068.txt

roleoftemporoman00risk_0098.txt

AA00012901_00001_0149.txt

roleoftemporoman00risk_0014.txt

AA00012901_00001_0112.txt

roleoftemporoman00risk_0005.txt

AA00012901_00001_0150.txt

AA00012901_00001_0047.txt

AA00012901_00001_0146.txt

roleoftemporoman00risk_0156.txt

roleoftemporoman00risk_0100.txt

AA00012901_00001_0029.txt

roleoftemporoman00risk_0084.txt

roleoftemporoman00risk_0088.txt

roleoftemporoman00risk_0092.txt

roleoftemporoman00risk_0036.txt

AA00012901_00001_0142.txt

roleoftemporoman00risk_0075.txt

roleoftemporoman00risk_0071.txt

AA00012901_00001_0067.txt

AA00012901_00001_0098.txt

AA00012901_00001_0040.txt

roleoftemporoman00risk_0027.txt

AA00012901_00001_0061.txt

roleoftemporoman00risk_0066.txt

AA00012901_00001_0095.txt

roleoftemporoman00risk_0061.txt

roleoftemporoman00risk_0070.txt

roleoftemporoman00risk_0127.txt

roleoftemporoman00risk_0166.txt

roleoftemporoman00risk_0122.txt

roleoftemporoman00risk_0104.txt

roleoftemporoman00risk_0051.txt

AA00012901_00001_0136.txt

AA00012901_00001_0051.txt

roleoftemporoman00risk_0007.txt

roleoftemporoman00risk_0062.txt

AA00012901_00001_0003.txt

AA00012901_00001_0005.txt

roleoftemporoman00risk_0035.txt

AA00012901_00001_0023.txt

roleoftemporoman00risk_0130.txt

roleoftemporoman00risk_0059.txt

AA00012901_00001_0036.txt

EKP2RBVIV_J3QFRT_xml.txt

AA00012901_00001_0044.txt

roleoftemporoman00risk_0076.txt

AA00012901_00001_0014.txt

AA00012901_00001_0148.txt

AA00012901_00001_0130.txt

AA00012901_00001_0102.txt

roleoftemporoman00risk_0140.txt

AA00012901_00001_0167.txt

roleoftemporoman00risk_0111.txt

AA00012901_00001_0120.txt

roleoftemporoman00risk_0001.txt

AA00012901_00001_0017.txt

AA00012901_00001_0129.txt

roleoftemporoman00risk_0060.txt

AA00012901_00001_0042.txt

AA00012901_00001_0041.txt

roleoftemporoman00risk_0011.txt

roleoftemporoman00risk_0094.txt

AA00012901_00001_0048.txt

AA00012901_00001_0030.txt

roleoftemporoman00risk_0163.txt

AA00012901_00001_0020.txt

roleoftemporoman00risk_0143.txt

AA00012901_00001_0110.txt

AA00012901_00001_0096.txt

AA00012901_00001_0083.txt

AA00012901_00001_0090.txt

roleoftemporoman00risk_0112.txt

roleoftemporoman00risk_0065.txt

roleoftemporoman00risk_0125.txt

AA00012901_00001_0169.txt

AA00012901_00001_0080.txt

roleoftemporoman00risk_0161.txt

AA00012901_00001_0107.txt

roleoftemporoman00risk_0053.txt

roleoftemporoman00risk_0101.txt

roleoftemporoman00risk_0031.txt

roleoftemporoman00risk_0034.txt

AA00012901_00001_0011.txt

AA00012901_00001_0125.txt

roleoftemporoman00risk_0024.txt

AA00012901_00001_0066.txt

roleoftemporoman00risk_0006.txt

roleoftemporoman00risk_0128.txt

AA00012901_00001_0009.txt

roleoftemporoman00risk_0047.txt

AA00012901_00001_0063.txt

roleoftemporoman00risk_0137.txt

AA00012901_00001_0010.txt

AA00012901_00001_0018.txt

roleoftemporoman00risk_0144.txt

roleoftemporoman00risk_0080.txt

roleoftemporoman00risk_0003.txt

roleoftemporoman00risk_0073.txt

AA00012901_00001_0097.txt

AA00012901_00001_0094.txt

roleoftemporoman00risk_0114.txt

roleoftemporoman00risk_0147.txt

AA00012901_00001_0038.txt

AA00012901_00001_0064.txt

roleoftemporoman00risk_0043.txt

roleoftemporoman00risk_0126.txt

roleoftemporoman00risk_0090.txt

roleoftemporoman00risk_0082.txt

roleoftemporoman00risk_0157.txt

roleoftemporoman00risk_0099.txt

AA00012901_00001_0001.txt

roleoftemporoman00risk_0124.txt

roleoftemporoman00risk_0148.txt

AA00012901_00001_0089.txt

roleoftemporoman00risk_0154.txt

roleoftemporoman00risk_0022.txt

roleoftemporoman00risk_0142.txt

AA00012901_00001_0081.txt

roleoftemporoman00risk_0086.txt

roleoftemporoman00risk_0019.txt

AA00012901_00001_0119.txt

AA00012901_00001_0133.txt

AA00012901_00001_0016.txt

AA00012901_00001_0114.txt

AA00012901_00001_0004.txt

AA00012901_00001_0028.txt

roleoftemporoman00risk_0155.txt

roleoftemporoman00risk_0149.txt

roleoftemporoman00risk_0133.txt

AA00012901_00001_0006.txt

roleoftemporoman00risk_0083.txt

AA00012901_00001_0025.txt

roleoftemporoman00risk_0107.txt

AA00012901_00001_0165.txt

roleoftemporoman00risk_0110.txt

roleoftemporoman00risk_0004.txt

AA00012901_00001_0100.txt

AA00012901_00001_0154.txt

AA00012901_00001_0079.txt

roleoftemporoman00risk_0044.txt

roleoftemporoman00risk_0103.txt

AA00012901_00001_0137.txt

AA00012901_00001_pdf.txt

AA00012901_00001_0002.txt

AA00012901_00001_0060.txt

roleoftemporoman00risk_0141.txt

roleoftemporoman00risk_0013.txt

AA00012901_00001_0139.txt

AA00012901_00001_0159.txt

AA00012901_00001_0141.txt

roleoftemporoman00risk_0108.txt

roleoftemporoman00risk_0046.txt

AA00012901_00001_0021.txt

roleoftemporoman00risk_0015.txt

roleoftemporoman00risk_0164.txt


Full Text










THE ROLE OF THE

TEMPOROMANDIBULAR JOINT

IN MEDIATING PERCEPTION

OF MANDIBULAR POSITION



by



JOHN EDWARD RISKI


A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF

THE UNIVERSITY OF FLORIDA

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE

DEGREE OF DOCTOR OF PHILOSOPHY



UNIVERSITY OF FLORIDA

1976














ACKNOWLEDGEMENTS


The author wishes to extend his sincerest gratitude

to his committee members, Drs. Ed Hutchinson, Bill Williams,

Chick LaPointe, and Parker Mahan. Throughout the project

they provided continued encouragement and assistance.

Acknowledgement is extended also to Dr. Joe Meier and

Mr. Harry Canter of Millersville State College, Millersville,

Pennsylvania and to Dr. Paul Ross, Franklin and Marshall

College, Lancaster, Pennsylvania. These gentlemen were

instrumental in completing the statistical analysis of the

data.

Finally, the author wishes to acknowledge the assist-

ance of Linda McCullers, who aided in all stages of the

study. It is to Linda that this study is dedicated.















TABLE OF CONTENTS

PAGE

ACKNOWLEDGEMENTS..........................................ii

LIST OF TABLES.............................................. v

LIST OF FIGURES........................................... viii

ABSTRACT................................................... ix


CHAPTER

ONE INTRODUCTION....................................1

Anatomy and Physiology...........................2

Review of Literature........................... 19


TWO STATEMENT OF PROBLEM........................... 38

Statement of Purpose........................... 39

Specific Objectives............................. 39


THREE METHODS AND PROCEDURES.........................41

Subject Selection.............................. 41

Experimental Tasks ............................. 41

Experimental Procedures.........................51

Filming Procedures..............................54

Procedures for Data Collection .................55


FOUR RESULTS.........................................65

Analysis of Perceptual Tasks and Connected
Speech .........................................65

Analysis of Speech Tasks and Nonspeech
Oral Movements.................................86

iii









TABLE OF CONTENTS continued

CHAPTER PAGE

FIVE DISCUSSION....................................106

Anesthetization of the Auriculotemporal
Nerve .................................... 107

Effect of Pressure............................. 114

Conclusions ...................................120


APPENDIX.................................................123

BIBLIOGRAPHY .............................................150

BIOGRAPHICAL SKETCH...................................... 157














LIST OF TABLES

Table Page

1 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Range of Jaw Position for Ten Trials...66

2 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard..................................... 68

3 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination ........................... 70

4 Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination .......................... 71

5 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Left................73

6 Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Left ............................................. 74

7 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Right.............. 75

8 Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Right ............................................. 76

9 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination ........................78

10 Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Anterior-Posterior Jaw Positions....................79

11 Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination..............................80
v








LIST OF TABLES CONTINUED

Table Page

12 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Tip Elevation.........88

13 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Dorsum Elevation......91

14 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/o I/ .............................................. 93
15 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/eI/ ................ ............................ 94

16 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/aU/.............................................. 96

17 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/ I/ ...............................................97
18 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/isi/ ............................................. 99

19 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/asa,/ .......... .................................. 101

20 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/iki/ .............................................103
21 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/ -ka/ ........................ ................... 104

22 The Amount of Jaw Opening (in mm) for the
Initiation of Each of Ten Tasks Under the
Normal and Pressure Conditions................... 118
23 Elevate Tongue Tip............................... 124

24 Elevate Tongue Dorsum.................. .......... 127

25 Diphthong /aI/.................................... 130

26 Diphthong /eI/.................................... 132

27 Diphthong /aU/.................................. 134








LIST OF TABLES CONTINUED


Table Page

28 Diphthong /DI/..................................... 136

29 Vowel-Consonant-Vowel /isi/........................138

30 Vowel-Consonant-Vowel /a-soc /...................... 141

31 Vowel-Consonant-Vowel /iki/ ........................144

32 Vowel-Consonant-Vowel /a~k./ ....................... 147














LIST OF FIGURES
FIGURE PAGE

I Mandible: Left Lateral Aspect ................... ..5

2 Mandible: Left Medial Aspect......................7

3 Muscular Control of Mandibular Movement........... 10

4 Temporomandibular Articulation: Sagittal View....13

5 Temporomandibular Articulation: Frontal View.....14

6 Temporomandibular Ligament: Lateral View..........17

7 Sphenomandibular and Stylomandibular Ligaments:
Medial View................................... 18

8 Acrylic Blocks for Assessing Interdental
Thickness Discrimination......................... 44

9 Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination......45

10 Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination ...............48

11 Cephalostat and Pressure Device.................53

12 Defined Measurements and Their Associated
Positive and Negative Values.....................57

13 Means, Ranges, and S.D.'s of Vertical Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4)................................. 83

14 Means, Ranges, and S.D.'s of Horizontal Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4)...................................85














Abstract of Dissertation Presented to the Graduate Council of
the University of Florida
in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy




THE ROLE OF THE
TEMPOROMANDIBULAR JOINT
IN MEDIATING PERCEPTION
OF MANDIBULAR POSITION

by

John Edward Riski

August, 1976



Chairman: Edward C. Hutchinson

Cochairman: William N. Williams

Major Department: Speech


Measures of mandibular positioning and movement are

described for a series of selected speech and nonspeech tasks

under normal and experimental conditions. The purpose of the

study was to evaluate the role of the sensory mechanism of the

temporomandibular joint in mediating perception of mandibular

position by 1) measurement of the positioning of the mandible

during selected speech and nonspeech tasks following unilateral

auriculotemporal nerve block and 2) measurement of the position-

ing of the mandible during selected speech and nonspeech tasks

during the application of a light pressure to the contralateral

temporomandibular joint capsule.

ix








Four young adult males, with normal occlusion and no

history of temporomandibular joint dysfunction, served as sub-

jects. Each subject completed all of the tasks under a nor-

mal condition, anesthetization of the right auriculotemporal

nerve, and anesthesia with a light pressure (one to two

pounds per square inch) applied to the left temporomandibular

joint capsule.

Each subject completed tasks designed to test his abil-

ity to perceive the position of his mandible in the superior-

inferior, lateral-medial, and anterior-posterior dimensions and

discriminate differences in weights of capsules held between

the teeth. In addition, each performed a series of tasks re-

quiring speech sound production and tongue elevation. The

anesthetization procedure utilized in this study did not appear

to disrupt subjects' perception of mandibular position for

any of the tasks in or significantly alter the positioning

of the mandible for the speech sample used. However, the

application of pressure disrupted subjects' ability to dis-

criminate between pairs of jaw positions to the right of

midline. Further, the application of pressure significantly

reduced the amount of jaw opening when the jaw opening was

observed to be greater than ten millimeters for the normal

condition.

The results of this study were interpreted to suggest

that the sensory mechanism of the temporomandibular joint, at

least the auriculotemporal nerve, has a minimal role in re-

gulating the positioning and movement of the mandible.









Further, these data suggested that pressure to the TMJ, on

the order of one to two pounds per square inch, inhibits the

translator motion of the condyle process.













CHAPTER ONE
INTRODUCTION


The oral structures primarily responsible for normal

speech articulation include the lips, tongue, velum, teeth,

and mandible. Considerable information is available rela-

tive to the normal placement and posture of these structures

for the production of normal speech elements. In addition,

several studies have demonstrated that there are identifiable

alterations in the speech signal following experimental

anesthetization of the oral structures (McCroskey, 1958;

McCroskey et al., 1959; Ringel and Steer, 1963; Schliesser

and Coleman, 1968; Gammon et al., 1971; and Scott and Ringel,

1971a).

Further, a growing body of literature exists which deals

with the assessment of mandibular function. Specific varia-

tions in mandibular placement have been observed for the pro-

duction of certain speech sound elements (Kent and Moll, 1972

and Owens, 1973). The independent, yet complimentary, actions

of the tongue and the mandible and the lower lip and the man-

dible have been recently described (Kent, 1972 and Sussman

et al., 1973). Other studies have demonstrated that subjects'

ability to perceive mandibular position for nonspeech tasks

is disrupted by anesthetization of the temporomandibular joint

(TMJ) capsule (Thilander, 1961). It has been reported also

that disruption in the perception of mandibular position,








caused by unilateral anesthetization of the TMJ capsule, can

be normalized by applying a painless pressure to the contra-

lateral capsule (Larsson and Thilander, 1964). A review of the

literature has failed to reveal any further information rela-

tive to the influence of anesthetization of the TMJ on the

control of mandibular position during speech function.

Therefore, the purpose of this study is basically

twofold: 1) to determine the effect of unilateral anestheti-

zation of the TMJ on normal subjects' ability to position the

mandible during selected speech and nonspeech tasks and

2) to determine the effect of a painless pressure administered

to the TMJ contralateral to the one anesthetized on subjects'

ability to position the mandible during the same selected

speech and nonspeech tasks.


Anatomy and Physiology


The mandible, or lower jaw, is comprised of a horizontal

portion, the body, and two vertical portions, the rami. The

rami unite inferiorly with the ends of the body. Superiorly,

the rami articulate with the temporal bone by way of the TMJ.

The complex movements of the mandible are made possible by

two groups of muscles, the muscles of mastication and the

suprahyoid muscles, and by the intricate function of the TMJ'S.

The purpose of this discussion is to describe the anatomy and

the physiology of the mandibular complex including the mandible,

the muscles that influence its movement and mandibular articu-

lation with the skull. The following account relies primarily

on the description of Enlow (1971), Gray (1959), Mahan (1967),









Sicher and DuBrul (1970), and Zemlin (1968).


Mandible: Origin and Growth

The body of the mandible is horseshoe shaped and ex-

tends upward and backward on both sides into the mandibular

ramus. The ramus extends upwards from the mandibular angle

and ends in two processes, the anterior, muscular coronoid

process and the posterior, articular condylar process. The

mandible is formed embryologically from the first branchial

arch, which is known also as the mandibular arch. The first

arch ultimately gives rise to the lower lip, the muscles of

mastication, the mandible, the anterior portion of the tongue,

and some of the middle ear structures. The mandibular arch

is joined with the maxillary processes at the extreme lateral

and rostral margins. The progressive anterior fusion between

these two processes reduces the width of the primative oral

fissure and forms the cheeks. At birth, the mandible is di-

vided into halves. It contains the alveoli for the deciduous

dentition. The angle of the ramus with the mandibular plane

is obtuse, about 170 Shortly after birth, the two halves

of the mandible become fused at the symphysis, beginning from

below. Fusion is usually complete by the first year. With

growth, the angle of the mandible becomes less and less obtuse.

At four years of age, it is about 140 and in the adult man-

dible, the angle is about 110* -120 .

The growing mandible enlarges in a forward and downward

manner with respect to the cranial base. However, the actual

course of growth proceeds in a complex process of bone








deposition and resorption predominantly in the posterior

and superior direction. The overall growth of the mandible

is associated with regional growth areas, which include

virtually all of the inner and outer surfaces of the mandi-

ble. These areas of growth include the neck of the condyle,

the coronoid process, the lingual tuberosity, the trihedral

eminence, and the chin. The regional growth movements are

concerned with a continuous process of relocation in which

the various local parts become shifted progressively in order

to maintain constant positions relative to the remainder of

the growing enlarging mandible as a whole.

Adult Mandible

As noted earlier, the mandible consists of a horseshoe

shaped body, which continues upward and backward into the

mandibular ramus. The ramus ends in two processes, the con-

dylar and the coronoid. Figures 1 and 2 illustrate the lat-

eral and medial aspects respectively of the adult mandible.

The mental symphysis joins the left and right mandibu-

lar bodies. Externally, it appears as a faint ridge. The

ridge divides inferiorly and encloses a triangular eminence,

the mental protuberance, which is depressed in the center,

but is raised on either side to form the mental tubercles.

The incisive fossa are the depressions lateral to the sym-

physis and just below the incisor teeth. The incisive fossa

are the origin of the mentalis and a small portion of the

orbicularis oris muscles. The mental foramen is found below

the second premolar tooth, midway between the inferior and


























,-'





. .. ; ... .,,<,


Body

Mental Protuberance

Mental Foramen

Oblique Line

9. Mandibular


5. Alveolar Process

6. Ramus

7. Condylar Process

8. Coronoid Process
Notch


Figure 1
Mandible: Left Lateral Aspect








superior borders of the body. The mental vessels and nerve

exit at the foramen. The oblique line is the faint ridge,

which proceeds posteriorly and superiorly from the mental

foramen becoming continuous with the anterior border of the

ramus. It provides attachments for the quadratus labii

inferior and triangularis; the platysma attaches just infer-

ior to the oblique line. The superior surface of the man-

dibular body is the tooth-bearing alveolar process. It is

hollowed into numerous cavities alveolii) for the reception

of teeth. The alveolar process resorbs with tooth loss re-

sulting in a reduced vertical dimension of the mandible.

The ramus of the mandible is directed superiorly from

the posterior portion of the body of the mandible. The ramus

divides superiorly into the condylar and the coronoid pro-

cesses. These processes are separated by the mandibular or

the semilunar notch. The anterior, coronoid process serves

as the point of attachment for the temporalis muscle. The

condyloid process frames the mandibular head, which articu-

lates with the mandibular fossa of the temporal bone by way

of the TMJ. The lateral surface of the ramus gives attach-

ment to the masseter muscle throughout nearly its whole ex-

tent.

The medial aspect of the mandible is illustrated in

Figure 2. Two small posteriorly directed spines are pro-

jected near the symphysis. These ridges or mental spines

are placed one above the other and serve as the origin for

the genioglossus muscle. The geniohyoid muscle originates

just inferior to the mental spines. Inferior and lateral to

the mental spines are the attachments for the anterior belly













































1. Mental Spines 3. Mandibular Foramen

2. Mylohyoid Line 4. Mylohyoid Groove

5. Angle of Mandible


Figure 2
Mandible: Left Medial Aspect








of the digastricus. The mylohyoid line extends posteriorly

and superiorly from the interior part of the symphysis. The

mylohyoid originates along this line. The superior pharyn-

geal constrictor originates, in part, from the posterior por-

tion of the line near the alveolar margin.

The medial surface of the ramus is marked near its

center by the mandibular foramen for the entrance of the in-

ferior alveolar vessels and nerve. The mylohyoid groove

runs obliquely inferiorly and anteriorly from the foramen

and houses the mylohyoid vessels and nerve. The angle of

the mandible provides attachments for the masseter laterally

and the internal pterygoid on its medial aspect. The internal

aspect of the ramus also provides attachments for several

ligaments. The attachments and ligaments will be discussed

later as a group.

Mandibular Musculature

The mandible is influenced in its movements and posi-

tioning by all of the muscles that attach to it. Further-

more, all mandibular muscles are active in all movements of

the mandible as their roles shift from movers to balancers

to holders (Sarnat, 1964). Two groups of muscles are of

prime concern. They are the muscles of mastication and the

suprahyoid muscles. Two other group of muscles are of se-

condary importance. They are the infrahyoid muscles, which

serve to stabilize the hyoid bone and the cervical column

and the post vertebral muscles, which serve to stabilize the

cranium, (Sicher and DuBrul, 1970 and Perry, 1973). The









focus of this discussion will be the two primary muscle

groups. The mandibular musculature can be divided by func-

tion or by muscles groups. For the purpose of this discus-

sion the musculature will be considered in muscle groups.

The direction of mandibular movement by each of the muscles

is illustrated in Figure 3.


Muscles of Mastication

Masseter. This muscle originates along the zygomatic

arch and zygomatic process and inserts along the ramus, the

coronoid process and the angle of the mandible. It is in-

nervated by the mandibular branch of the Trigeminal nerve and

serves to elevate the mandible.

Temporalis. This muscle has its origin on the floor of

the temporal fossa and the temporal facia. It inserts along

the anterior border of the coronoid process and the anterior

border of the ramus of the mandible. It is also innervated

by the mandibular branch of the Trigeminal nerve. It func-

tions to elevate and retract the mandible.

External Pterygoid (Lateral). This muscle originates

from the greater wing of the sphenoid and the lateral sur-

face of the lateral pterygoid plate. It inserts on the

anterior portion of the neck of the condylar process and the

meniscus of the mandibular joint. It is innervated by the

mandibular branch of Trigeminal nerve and serves to protrude

the mandible and pull the articular disc anteriorly. It

also assists in the rotary movement of the mandible for

chewing.











































Muscles of Mastication

M: Masseter

Te: Temporalis

EPy: External Pterygoid

IPy: Internal Pterygoid


Suprahyoid Muscles

Mh: Mylohyoid

Gh: Geniohyoid

Dab: Anterior Belly
of Digastric


Figure 3
Muscular Control of Mandibular Movement
After Cole (1971)








Internal Pterygoid (Medial). The origin of this muscle

is along the lateral pterygoid plate and the perpendicular

plate of the palatine bone. Insertion into the mandible is

along the posterior medial surface of the ramus and the

angle of the mandible, and innervation is from the mandibu-

lar branch of the Trigeminal nerve. It serves to protrude

and to elevate the mandible and also assists in the rotary

movement for chewing.


Suprahyoid Muscles

Mylohyoid. This muscle originates along the mylohyoid

line of the mandible and inserts along the median raphe from

the chin to the hyoid bone. It is innervated by the mylo-

hyoid branch of the Trigeminal. It elevates the hyoid bone

and the base of the tongue, but also assists in depressing

the mandible.

Geniohyoid. The mental spine of the mandible is the

origin of this muscle. It inserts on the body of the hyoid

bone and is innervated by the first and second cervical

nerves through the Hypoglossal nerve. It functions to ele-

vate the hyoid bone and move it anteriorly as well as to de-

press the mandible.

Digastricus (anterior belly). The anterior belly of

the Digastricus originates from the inner surface of the

mandible near the symphysis. It inserts into the inter-

mediate tendon of the hyoid bone. It is innervated by the

mylohyoid branch of the Trigeminal nerve. It also serves

to elevate the hyoid bone and to depress the mandible.








Temporomandibular Articulation

The TMJ is unique among all the joints of the human

body. It is a gynglmoarthrodial (sliding hinge) joint.

Unlike most articulating surfaces, the TMJ is not covered

by hyaline cartilage, but rather, is covered by an avascu-

lar, fibrous protein, collagen. Also unique to the TMJ

articulation is the fact that the two articulating complexes

house teeth, whose shape and position guide the joint when

teeth come to occlusion. Finally, the bilateral articula-

tion with the skull restricts certain mandibular motions,

such as lateral movement. The sliding and hinge movement

of the TMJ is possible because of an articular disc or

meniscus interposed between the temporal bone and the con-

dylar process of the mandible, thus dividing the articular

space into an upper and a lower compartment. Figure 4

illustrates a sagittal section of the TMJ articulation. The

hinge or rotational movement occurs between the condyle and

articular disc while the sliding or translational movement

occurs between the temporal bone and the meniscus.

The articular disc is a thin oval plate with tight

lateral and medial attachments to the condyle, an elastic

posterior attachment to the tympanic plate of the temporal

bone and an anterior attachment to the articular capsule

and to the lateral pterygoid muscle. The shape of the disc

is such that it accommodates itself with the surface of the

condylar process below and temporal bone above.

The TMJ is surrounded by a thin articular capsule,

which is illustrated in Figure 5. The capsule is loosely





















44 .-., /'.._ .-






















1. Mandibular Condyle 4. Upper Synovial Cavity

2. Articular Disc (Meniscus)5. Lower Synovial Cavity

3. Temporal Bone 6. Mandibular Fossa

7. Articular Eminence


Figure 4
Temporomandibular Articulation: Sagittal View
























*Li Le


1. Articular Capsule

2. Mandibular Fossa

3. Condylar Process


Articular Disc (Meniscus)

Upper Synovial Cavity
Lower Synovial Cavity


Figure 5
Temporomandibular Articulation: Frontal View








attached to the articulatory surfaces of the mandibular

fossa and to the neck of the condylar process laterally,

medially, and anteriorly. The capsule thickens laterally

into the temporomandibular ligament which will be included

in the following discussion. Except for the thickening, the

capsule is loosely organized in its lateral aspect and the

lateral aspect of the anterior wall. The medial aspect of

the anterior wall has attachments to the articular disc and

to the lateral pterygoid muscle. The medial and posterior

walls of the capsule are present but also loosely organized.

In translational movements, the condyle is pulled anteriorly

onto the articular eminence. As the meniscus is tightly

attached to the condyle while having only an elastic attach-

ment posteriorly to the tympanic plate of the temporal bone,

the meniscus translates anteriorly with the condyle. How-

ever, the attachment of the meniscus to the condyle is not

rigid enough to prevent movement of the condyle against the

meniscus in a horizontal plane during hinge as rotary move-

ment of the mandible.

The first stage of mandibular depression is a simple

hinge action, and only the lower compartment is used as the

head of the condyle rotates along the inferior surface of

the articular disc. As the mandible is further depressed,

translation begins between the disc and the articular emi-

nence resulting in forward displacement of the condyle.

There are three ligaments which participate in TMJ

articulation. These ligaments are now believed to function

in limiting jaw movement at maximum open jaw positions and








to provide proprioceptive input to the central nervous

system via their Golgi tendon organs. These ligaments are

illustrated in Figures 6 and 7.

The temporomandibular ligament is comprised of two short

bundles, one anterior to the other. As noted earlier, this

ligament is a thickened portion of the articular capsule. The

ligament is attached superiorly to the zygomatic arch and

inferiorly to the lateral, posterior surface of the condylar

process.

The sphenomandibular ligament is a remnant of Mechel's

cartilage. The ligament arises from the angular spine of the

sphenoid bone and spreads fanlike downward and outward

finally attaching to the mandible ar the lingula of the man-

dibular foramen.

Lastly, the stylomandibular ligament extends from near

the apex of the styloid process of the temporal bone to the

angle and posterior border of the ramus of the mandible.

Sensory innervation to the TMJ capsule is supplied

primarily by the auriculotemporal nerve of the mandibular

branch of the Trigeminal nerve. Small slips of the masseteric

and posterior deep temporal nerve also supply the capsule

anteriorly.

Histological studies have provided further information

regarding the sensory innervation of the capsule. Thilander

(1961) demonstrated that the posterior and lateral aspects

of the capsule are the most richly innervated, while the

anterior and medial aspects are sparsely innervated and the

articular disc lacks any sensory innervation. Thilander found



















V '


1. Temporomandibular Ligament
2. Capsular Ligament
(Articular Capsule)



Figure 6
Temporomandibular Ligament:


Zygomatic Arch
Condylar Process


Lateral View













































1. Sphenomandibular Ligament

2. Angular Spine of Sphenoid

3. Mandibular Foramen


4. Stylomandibular Ligament

5. Styloid Process

6. Angle of Mandible


Figure 7
Sphenomandibular and Stylomandibular Ligaments:
Medial View








four types of nerve endings in the capsule. Free nerve

endings were the most abundant. Organized endings such as

Ruffini endings, Golgi tendon organs, and the Vater-Pacini

corpuscles are represented, but only sparsely.

Investigations of the role of joint receptors in

perception of position sense and kinesthesis by Mountcastle

and Powell (1959) provide further information of the sensory

capabilities of the TMJ joint receptors. They identified

two types of slowly adapting nerve endings. These endings

discharged at a steady rate that was influenced only by the

angle of the joint. Individual receptors responded to arcs

of 15 to 20 degrees. Thus, they functioned as absolute

detectors of joint angle. The two groups of endings were

the spray type Ruffini endings and the Golgi tendon organs,

both of which are present in the TMJ.

The blood supply to the TMJ capsule is through the

superficial temporal and maxillary arteries posteriorly and

from the twigs of the masseteric artery anteriorly. The

articular disc, which is avascular in its center, has an

unusually rich plexus of veins on the periphery. The plexus

serves to equalize pressure in the tissues by filling and

emptying as the condyle rocks rythmically forward and back-

ward in chewing.



Review of Literature

The purpose of this review is to present the current

understanding of oral sensation and perception with specific

reference to mandibular kinesthesia. In addition, mandibular








function will be discussed in reference to the physiological

processes of mastication, deglutition, and speech.


Sensory Interruption

Fairbanks (1954) proposed a feedback loop theory of

speech production in which he hypothesized that tactile and

kinesthetic feedback, in addition to auditory feedback, are

necessary for normal speech production. The importance of

auditory feedback for speech production is supported by the

results of investigations which have demonstrated that de-

laying the air borne auditory signal (delayed auditory feed-

back) of normal speakers typically results in an aberrant

speech pattern characterized by dysfluency, general articu-

lation inaccuracy and modification of speech sound duration,

the fundamental frequency and the sound pressure level (Lee,

1950; Black, 1951; and Fairbanks, 1955). The need for tactile-

kinesthetic information has been supported by researchers who

have demonstrated that there is a relationship between oral-

sensory integrity and articulation proficiency (McCroskey,

1958; McCroskey et al., 1959; Ringel and Steer, 1963: Schliesser

and Coleman, 1968; Thompson, 1969; Gammon et al., 1971; Scott

and Ringel, 1971a; Scott and Ringel, 1971b; Horii et al., 1972;

and Borden, 1973).

The task of oral stereognosis, which involves the iden-

tification of plastic shapes presented intra-orally has evolved

recently as a possible indicator of oral sensory integrity.

Research has indicated that the subjects' performance








on this task, which has been suggested to involve intra-oral

movements similar to those in speech production, is severely

disrupted by mandibular block anesthesia (Schliesser and

Coleman, 1968 and Thompson, 1969).

A positive relationship between speech skills and oral

stereognosis has been established also (Moser et al., 1967;

Ringel et al., 1968; Weinberg 1970; Fucci and Robertson,

1971; and McNutt, 1973). These studies have demonstrated that

articulatory defective individuals without any known structural

or organic pathologies perform poorer on tasks of oral stere-

ognosis than do their normal speaking counterparts. Further

evidence of a positive relationship between speech skills and

oral stereognosis is offered by Bishop et al. (1973). These

researchers compared the performance of manually educated

deaf individuals and to normal hearing speakers on a task of

oral stereognosis. The experimental group made more errors

on this task as well as making different types of errors as

compared to the other two groups. The authors suggested that

orosensorimotor functions develop, in part, through the prac-

tice of speech skills.

A discussion of sensory disruption is necessarily

followed by a discussion of feedback systems. The researchers

who initially investigated articulation under nerve block

anesthesia assigned monitoring abilities for any uneffected

articulatory events to other channels, presumably undisturbed

by the anesthesia. This reflects the view that all articula-

tory activities are monitored by some sensory channel. This








view of a closed-loop feedback system was reported by

MacNeilage (1970) and Abbs and Netsell (1973).

Hixon and Hardy (1964), on the other hand, proposed

that speech movements were programmed. This view was

supported by Kent (1973) who found time intervals between

articulatory events were too short to accommodate the use of

feedback. Kent (1973) proposed that speech is more likely

operating under open-loop control or that speech is pre-

programmed centrally. He postulated that feedback might be

employed in a reset capacity to allow for occasional

adjustment of the motor program.

Although much of the discussion regarding feedback

control is theoretical, interpretation of current evidence

suggests that both closed-loop and open loop control systems

are actively involved in motor control of speech (Putnam

and Ringel, 1972 and Abbs, 1973). Thus, after a speech

sequence is triggered initially as a unit, peripheral sensory

mechanisms make fine adjustments. Such a theory may help

explain why only minor distortions of the speech signal are

observed when bilateral mandibular blocks are performed.


Mandibular Position Movement

The limited amount of research on mandibular positioning

can be attributed to the absence of convenient and accurate

transduction techniques. Geissler (1971) outlined three

requirements for instrumentation. It should be able to record

a large number of patients, should not interfere with normal

mandibular movements, and should allow continuous recording

during mandibular movement.








Within the past several years, a number of techniques

have been developed to record mandibular movement during a

variety of functions. The techniques include cinefluoro-

graphy (Jankelson et al., 1953), the Case Gnathic Replicator

(Gibbs et al., 1966), the Perspex screen (Atkinson and

Shepherd, 1955), Photoelectric Mandibulography (Gillings

and Graham, 1964), and strain gauge devices (Sussman and

Smith, 1970). There are advantages and disadvantages to each

method. Some provide information of only two planes of

movement (Photoelectric Mandibulography, cinefluorography,

and the perspex screen). Others are expensive to operate

(Case Gnathic Replicator) or appear to interfere with normal

mandibular movement (strain gauges). Nonetheless, with this

variety of instrumentation, an understanding of mandibular

movement is developing.

Several measurement strategies have been developed

recently to study mandibular kinesthesia. These techniques

include duplicating an interdental space (Thilander, 1961)

and several methods of assessing interdental space discrim-

ination (Ringel et al., 1967; Williams and LaPointe, 1972;

and Williams et al., 1974). As a result of available

instrumentation and test methodology, there is a growing

body of literature on assessment of mandibular function.

Researchers have begun to define quantitatively mandibular

kinesthesia and mandibular function for the biophysiological

processes of the mastication, deglutitipn, and speech. Initial

attempts also have been made to define the sensory mechanism

responsible for









neuromuscular control of mandibular movement and positioning

for these processes. The following literature review presents

the current understanding of mandibular kinesthesia and man-

dibular and TMJ function for the processes of deglutition,

mastication, and speech.


Mandibular kinesthesia

Oral kinesthesia has been defined by Ringel et al.

(1967) as the sense by which muscular motion, weight, and po-

sition of an oral structure is perceived. Rose and Mountcas-

tle (1959) previously established that intact joint receptors

and central nervous system relay networks are required for

kinesthesia. Mountcastle and Powell (1959) confirmed that

specific joint endings with cortical projections respond to

absolute degrees of arc or joint angles. Thus, defining

mandibular kinesthesia as the sense of perceiving the posi-

tion, motion, and weight of the mandibular structure appears

completely acceptable. Research indicates, however, that

Subjects' performance on tasks of interdental thickness dis-

crimination mandibularr position) is unrelated to their per-

formance on tasks of interdental weight discrimination and

that different receptors may be responsible for the percep-

tion of mandibular position and the interdental perception

of weight (Williams and LaPointe, 1972).

The study of mandibular kinesthesia in normal human

individuals has concentrated primarily on subjects' ability

to discriminate differences in mandibular positions. Although

instrumentation has varied, the results reported by various








investigators have been remarkably similar. Thilander (1961)

described a task which required subjects to choose a random

jaw position between the rest position and maximum jaw open

position and then to replicate that position ten times. Under

normal conditions, the subjects came within plus or minus

1.6 mm of duplicating this position over 20 trials. Ringel

et al. (1967) used a modified vernier-type caliper placed

between the biting surfaces of the upper and lower central

incisors. Their results indicated that absolute difference

limen values are relatively independent of the degree of

mouth opening. They reported an average difference limen of

2.04 mm. Williams and LaPointe (1972) and Williams et al.

(1974) used pairs of plastic blocks and pairs of plastic

wedges to attain difference limens. With the use of pairs

of plastic blocks, they reported an average difference limen

of 1.91 mm. They concluded also that interdental thickness

discrimination was independent of mouth opening. Williams

et al. (1974) used pairs of plastic wedges (the wedges

required quided mandibular motion to a given position), to

establish difference limens and reported an average difference

limen of 1.37 mm. They suggested that the lower difference

limen, using the wedges, reflected the mandibular movement

required by the instrumentation and provided subsequent

activation of additional sensory receptors in the TMJ.

Further understanding of the sensory mechanism of

mandibular kinesthesia has been gained from other studies

of interdental thickness discrimination. Originally, the








receptors responsible for mediating the sense of mandibular

position were thought to be housed in the TMJ capsule, muscles

of mastication, or possibly the periodontal ligament

(Thilander, 1961). Studies of interdental thickness discrim-

ination comparing the performance of dentulous and edentulous

subjects suggest that the periodontal ligament is not respon-

sible for perception of mandibular position (Manly et al., 1952;

Kawamura and Watanabe, 1960; Woodford, 1964; and Siirila and

Laine, 1963). Again, although instrumentation and methodology

differed slightly, several groups of researchers have reported

that the ability to detect thicknesses or difference in thick-

nesses does not differ appreciably between dentulous and

edentulous subjects. Discrimination of thickness appears

equally good between natural incisors and natural molars

(Kawamura and Watanabe, 1960 and Siirila and Laine, 1963).

Neither is there any significant difference in perception

threshold when both upper and lower antagonistic teeth are

anesthetized (Siirila and Laine, 1963), nor when the alveolar

mucosa is topically anesthetized (Manly et al., 1952).

Woodford (1964) found that edentulous subjects performed

equally as well on a task of thickness discrimination with or

without their dentures.

The TMJ's sensory mechanism has been implicated as

performing an active role in mandibular kinesthesia in re-

search by Thilander and her colleagues. Thilander (1961)

hypothesized that disrupting the sensory mechanism would impair

perception of mandibular position. She developed a task for








assessing mandibular kinesthesia which required subjects to

choose an arbitrary jaw position between mandibular rest

position and maximum opened jaw position and then attempt

to replicate that position ten times in close succession.

From the results of a series of experiments, including uni-

lateral and bilateral anesthetization of the TMJ capsules

and anesthetization of the inferior nerve, she concluded

that the TMJ capsule is responsible at least in part, for

mediating perception of mandibular position. More speci-

fically, subject performance varied from normal only under

conditions of unilateral and bilateral anesthetization of the

TMJ capsule. Subject performance was disrupted equally under

unilateral and bilateral anesthetization.

The findings of Larsson and Thilander (1964) prove

quite provocative. These researchers evaluated the effects

of certain "distracting" stimuli including stroboscopic light

flicker, sound stimulis (clicks), stimulation of the right

median nerve, painful pressure applied on the joint, and pain-

ful pressure applied anterior to the joint on subjects' abi-

lity to replicate arbitrary jaw position (Thilander, 1961).

The subjects performed significantly poorer than normal un-

der all conditions of "distracting" stimuli except when

painful pressure was applied to the joint. Performance under

this condition did not vary from normal. Further investiga-

tion of this phenomena revealed that a more moderate, pain-

less pressure could normalize the disruptive effects of any

of the "distracting" stimuli and even more remarkably, a








painless pressure could normalize the disruptive effects

of unilateral anesthetization of the TMJ capsule when the

pressure was administered to the contralateral joint capsule.

The authors theorized that the normalizing effect was the re-

sult of activation of nervous elements in the richly inner-

vated lateral aspect of the capsule. They also explained

that there may be alteration in the tension of the capsule

requiring less movement than normal to discharge receptors.

Thus, positional changes could be perceived more readily.

Ransjo and Thilander (1963) demonstrated that the func-

tion of the TMJ receptors is impaired in TMJ disorders

ascribed to malocclusion, but not dysfunctions of myogenic

origin. Storey (1968) interpreted these results as indi-

cating that the masticatory muscles are not involved in per-

ception of mandibular position. Ransjo and Thilander (1963)

reported also that in cases of unilateral TMJ dysfunction

again a painless pressure applied to either the intact joint

or both joints would normalize the perception of mandibular

position. The impaired perception of mandibular position in

the malocclusion group could also be normalized by adjusting

and correcting the malocclusion.

Finally, Posselt and Thilander (1965) studied the role

of the TMJ receptors in controlling border movements (extreme

positions) of the mandible. They reported significant in-

creases in maximum vertical jaw opening under conditions of

unilateral and bilateral anesthestization of the TMJ capsules.

They concluded that the TMJ ligaments participate not only in








mediating the perception of position, but also appear to act

as a protective mechanism during extreme open positions of

the mandible.

The evidence to date suggests that a subject's ability

to perceive and/or to discriminate between different mandi-

bular positions, as measured by tasks of interdental thickness

discrimination, is independent of the presence of natural

or artificial dentition. In addition, this ability also

appears to be independent of the sensory integrity of the an-

tagonistic teeth. However, there is strong evidence that the

nerve endings in the TMJ are responsible, at least in part,

for mediating perception of mandibular position.

More recently, Siirila and Laine (1972) presented the

results of a study designed to study the effect of anesthesia

of the TMJ capsule on subjects' ability to judge between dif-

ferences in mouth opening. These researchers used a modi-

fied caliper to establish the difference necessary to descrim-

inate mouth openings from a series of standard openings.

Subjects' performance under bilateral intracapsular TMJ

anesthesia was equivalent to their performance for the normal

condition. They concluded that different sensory mechanisms

might be involved in replicating a mouth opening (Thilander,

1961) and their task of size discrimination. However,

Siirila and Laine's (1972) test protocol allowed subjects

to tap their teeth against the test instrument. Tapping

very likely activated sensory endings in the periodontal

ligament and receptors in the TMJ that respond to movement.








Williams and LaPointe (1974), reported earlier, suggested that

smaller values of mouth opening may be discriminated when TMJ

movement is allowed.

Deglutition mastication

The process of deglutition and mastication have been

described narratively by Fletcher (1970 and 1971). Fletcher

(1970) described the role of the mandible in a mature

swallow as providing a stable base from which the oral

structures function as they collect a bolus and force it

posteriorly. A graphic description of mandibular movement

during mastication has been provided recently by Gibbs et al.

(1971) and Gibbs and Messerman (1972). Using the Case Gnathic

Replicator (Gibbs et al., 1966), they were able to record

graphically mandibular motion in three planes of movement.

Many of their comparisons of the mandibular masticatory

process were relative to mandibular movement for speech

function. For example, they found that the maximum vertical

opening for chewing was typically two to four times more than

the vertical opening for speech. The amount of vertical

opening during speech was relatively equal between subjects

while it varied considerably for chewing. Speech function

involved little lateral motion of the mandible whereas there

was a great deal of lateral movement during chewing. Hori-

zontal or anterior-posterior movement of the mandible appeared

equal for both processes, however, it was proportionately

greater in relationship to vertical movement for speech. There

was asymetrical motion of the condyles during mastication.








The working condyle, on the side with the food, reached the

maximum opening first. The mandible stopped movement during

chewing for a brief time at its closed stage. Condylar move-

ment was prominent in masticatory function, but not for speech.

Finally, the average maximum velocities for chewing were

considerably greater than for speech (6.05 in./sec. and 1.65

in./sec. respectively). Gibbs and Messerman (1972) concluded

that much important information concerning mandibular movement

for speech could be obtained from measuring the vertical and

horizontal motion exclusively.

Interest in mandibular movement for deglutition and the

masticatory process necessarily implies interest in the systems

neurocontrol mechanism. Ingervall et al. (1971) examined the

occlusal positions of the mandible and the movements of the

hyoid bone with and without anesthesia of the TMJ capsules.

These researchers reported that dental contact was common

during swallowing and could find no differences in positions

between swallowing prior to or during anesthetization. The

hyoid bone movement patterns were also independent of the

anesthesia condition.

Ingervall et al. (1972) utilized the films collected

earlier (Ingervall et al., 1971) and evaluated the influence

of the receptors in the TMJ capsules on the duration of

swallowing and movements of the hyoid bone. They reported

that bilateral anesthetization of the TMJ capsule had no effect

on the duration of the movement of the hyoid bone. This is not








too surprising since the swallow patterns include dental

occlusion and thus provided added feedback from the perio-

dontal ligament. In addition, there is no reason to suspect

that the temporomandibular articular receptors provide any

feedback which would influence the oral structures involved

in swallowing as they appear to be more active in conscious

positioning of the mandible and the mandible is already po-

sitioned at the iniation of the swallow sequence.

Several other researchers have explored the nature of

the control of the mandible for dynamic masticatory function

either directly or indirectly. Shepherd (1960) reported that

the total movement of the mandible decreased with age, use

of dentures, and introvert personality type. Denture wearers

demonstrated similar masticatory patterns with and without

their dentures, however, as might be expected, the amount of

vertical movement was much greater without dentures. The

masticatory pattern was also unchanged prior to and after

complete teeth extraction. However, abnormal masticatory

patterns were evident in individuals who demonstrated exces-

sive occlusal wear and who had pain, clicking, or other symp-

toms of TMJ dysfunction. The author reported that in no case

where the TMJ was showing abnormal symptoms was the associated

masticatory cycle considered to be normal. In many cases,

marked irregularities occurred in the patterns with a lack of

smoothness in individual cycles and sometimes there was a

complete lack of rythm from cycle to cycle.

These findings were supported by Atkinson and Shepherd

(1961). In one patient whose TMJ dysfunction was diagnosed








as resulting from malocclusion, the malocclusion was adjusted

with an appliance. The resulting masticatory movement was

found to be much smoother.

In a study reported by Schaerer et al. (1966), anesthesia

of the TMJ capsules and periodontal ligament did not effect

mandibular movements, muscle activity, or contact between teeth

during chewing. Thus, it appears that mandibular movement and

positioning during the processes of deglutition and mastication

in normal individuals is not disrupted by anesthetizing the

TMJ. However, abnormal masticatory patterns have been observed

in individuals who have demonstrated excessive occlusal wear

and have had pain, clicking, or other symptoms of TMJ dysfunc-

tion. This might suggest that long standing disruption of

TMJ function is necessary before there is observable altera-

tion in the masticatory stroke.


Speech function

The initial interest in mandibular movement and position

during speech appears to have been generated by researchers in

the field of prosthetic dentistry. Simple phonetic tests, such

as counting from one to ten or repeating /s/ loaded words,

hve been used to establish "closest speaking space" or closest

interdental space in the construction of clinically accepted

dentures (Geissler, 1971 and Gillings, 1973).

Recently, speech researchers have begun to measure

mandibular position for speech function while systematically

varying phonetic context. The results of the research from








these two areas is in close agreement and can be summarized

and discussed together. Another current investigation of

speech and masticatory function (Gibbs and Messerman, 1972)

has been discussed earlier and will not be included here.

There seems to be a general agreement among researchers

that jaw position is lower for vowel sounds (/a/,/2/), diph-

thongs (/al/), and back consonant (/k/,/g/) production and is

more elevated for high vowels (/i/,/u/) and front consonant

(/p/,/s/) production. The mandible has been observed to dis-

place posteriorly as it displaces inferiorly. Kent and Moll

(1972) and Owens (1973) have explained that this is due to

the hinge-type movements of the condyle for the mandible's

speech movements. It is also recognized that adjacent pho-

nemes may cause mandibular position to vary slightly for any

one phoneme. Geissler (1971) has demonstrated further that

mandibular movement may vary with speaking rate, becoming

less as speaking rate increases. Geissler (1971) and Gillings

(1973) have observed also that while mandibular position for

closed sounds tends to be fairly consistent from individual

to individual, the position of the mandible varies from in-

dividual to individual for open sounds. Although there is

obviously room for continued research in this area, it is

apparent that specific mandibular positions are responsible

for specific phonetic productions.

Other areas of mandibular dynamics are also currently
under investigation. New research is providing information

that is beginning to explain the complex interplay between

the dynamic mandible and other articulators including the lips








and the tongue. It is now obvious that the tongue does not

move in complete harmony with the mandible (Kent, 1972).

Kent (1972), who studied the relationship of tongue body and

mandibular movement during speech, concluded that the overall

displacements of the tongue body and jaw vary with phonetic

context. He also identified a "trading relationship" between

the tongue and the mandible; the smaller the amount of jaw

movement, the greater must be the extent of tongue motion.

Sussman et al. (1973) reported that although the jaw

and the lower lip are mechanically linked and constrained by

each other, they also act as independent articulators, each

reflecting their own specific movement characteristics. He

also reported that the less the jaw contributes to the forma-

tion of a bilabial stop, the higher the elevation of the lower

lip.

This independence in movement between jaw and tongue

and jaw and lip might be interpreted as evidence for separate,

yet interconnecting feedback systems where one system is

responsible for monitoring the other and compensating for it.

Further research of mandibular and tongue body dynamics

reveals similarities in the relationship of movement velocity

to displacement. That is, the greater the displacement of the

structure during speech, the greater the velocity of movement

(Abbs et al., 1972; Sussman et al., 1973; and Kent and Moll,

1972).

There is research in the literature that assists in

understanding the complex interplay between the mandible and








the other oral structures during speech. Hansen (1952)

studied speech intelligibility using single words under

varying conditions of jaw restriction from full restriction

to no restriction. He found no differences in intelligi-

bility among any of the conditions. This researcher noted,

however, that a speech sample simulating connected speech

might yield different results. These findings are in agree-

ment with those of Kent (1972), who reported the indepen-

dence of tongue and jaw dynamics and the apparent compensa-

tory action between the two.

Weiss (1969a) disrupted lingual and palatal action

in eleven year olds and reported that this disruption does

not significantly effect the acoustic parameters of articu-

lation. Weiss (1969b) evaluated the lingual-palatal and

mandibular placement of the subjects of his earlier study.

He discovered that the tongue tip placement for some phonetic

productions were disrupted, although there was no signifi-

cant overall disruption. However, he did report that there

was greater mandibular displacement after anesthesia for the

phonemes /1/ and /I/, two phonemes that seem to involve less

tactile feedback than most. Following anesthetization, there

was also greater variation in the physiologic rest position

of the mandible. Weiss (1969b) questioned whether disrupted

action of one structure in the articulatory system affects

the function of another in the same system.

Sussman and Smith (1971) monitored and recorded jaw

movements under varying degrees of DAF. They reported no








overall disruptive effects of DAF on jaw positioning nor on

the duration of the velocity of jaw movement. However, they

did find isolated instances of disruption. Although not

statistically significant, there seemed to be a trend for the

jaw to overshoot its position for some vowels under the 0.3

second delay condition. They also reported a significant in-

crease in the length of jaw activity for the 0.1 second delay

condition. These results offer some evidence that auditory

feedback may be important in controlling mandibular position.

Research on mandibular function for speech processes

has demonstrated the vertical and horizontal positioning is

dependent on the phonemic makeup of the speech sample.

Current research has provided information of the independent,

yet complimentary actions of the mandible and the tongue

during articulation. Investigators who have disrupted lingual

tactile and auditory feedback during speech have reported only

minimal and inconsistent alterations of mandibular position.














CHAPTER TWO
STATEMENT OF PROBLEM


The literature reviewed in CHAPTER ONE suggests that

experimental anesthetization of the oral structures results

in quantifiable alterations in subjects' performance on

oral-sensory-perceptual tasks as well as alteration of cer-

tain characteristics of speech production. The literature

reviewed has revealed also that mandibular position is spe-

cific for certain phonetic productions. In addition, these

studies reveal that the sensory mechanism within the TMJ

apparently controls, to some degree, the movement and posi-

tioning of the mandible. Moreover, it would appear that

measurement strategies, such as duplicating an interdental

space (Thilander, 1961) or interdental thickness discrimin-

ation (Williams and LaPointe, 1972 and Williams et al.,

1974) might be used in determining as index of sensory in-

tegrity of the TMJ. The literature reviewed has demonstrated

further that the effect of anesthetizing one TMJ can be nor-

malized by a painless pressure applied to the contralateral

capsule (Larsson and Thilander, 1964).

If anesthetization of the TMJ causes impairment in the

regulation and control of mandibular position, and if fine

sensory motor coordination of jaw placement and movement is,

in fact, critical for the production of normal speech sounds,








it seems reasonable to suggest that disruption of the TMJ

sensory system would have a demonstrable effect on the overall

articulatory pattern of the mandible for speech production.

It might be suggested also then that the application of

pressure to the unanesthetized TMJ might be expected to have

a normalizing effect on mandibular patterns of movement and

positions for speech. However, a review of literature has

failed to identify any investigation directly concerned with

the role of the TMJ sensory mechanism as related to the

regulation and control of mandibular movement and positioning

for speech sound production.


Statement of Purpose


Therefore, the purpose of this study is basically two-

fold: 1) to determine what effects occur with unilateral

anesthetization of the TMJ relative to the positioning and

movement patterns of the mandible during selected perceptual

tasks, nonspeech oral movements, and a selected speech sample

and 2) to determine what effects occur with a subsequent

administration of a painless pressure to the TMJ capsule

opposite the one anesthetized on the positioning and movement

patterns of the mandible during selected perceptual tasks,

nonspeech oral movements, and a selected speech sample.


Specific Objectives

A series of tasks was devised in an attempt to measure

the effect of the anesthesia and pressure on the positioning








of the mandible. All of the tasks were performed under the

two experimental conditions and under a normal, control

condition with no anesthesia and no pressure. The three

categories of tasks included: 1) four perceptual measures

of mandibular position discrimination and one perceptual

measure of interdental weight discrimination, 2) two tasks

requiring nonspeech oral movements, and 3) nine tasks

requiring speech sound production. Thus, there was a total

of sixteen separate tasks.

The specific objectives of the study were:

1) to compare subjects' performance on each of the

five perceptual tasks under the two experimental conditions

and the one control condition,

2) to compare subjects' performance on each of the

two tasks requiring nonspeech oral movements under the two

experimental conditions and one control condition, and

3) to compare subjects' performance on each of the

three tasks requiring speech sound production under the two

experimental condition and one control condition.














CHAPTER THREE
METHODS AND PROCEDURES



Subject Selection

Four young adult males served as subjects. Their ages

range from 22 years, 4 months to 29 years, 4 months with a

mean age of 25 years, 11 months. The individuals who served

as subjects possessed all of their natural central incisors,

had an Angle Class ONE occlusion with a normal bite. None of

the subjects complained of any current or past history of TMJ

dysfunction. All subjects were monolingual speakers of the

General American Dialect and had no articulation or voice

disorders.


Experimental Tasks


Perceptual Measures

The perceptual measures utilized in this study were de-

signed to assess subjects' abilities to discriminate between

differences in mandibular positions and to discriminate be-

tween differences in weights placed between the maxillary and

mandibular incisors. The first perceptual measure required

each subject to duplicate an arbitrary interdental space.

This task was included as an attempt to replicate and verify

Thilander's initial research in the area of TMJ anesthetiza-

tion.








Three of the perceptual tasks were designed to assess

subjects' ability to discriminate between pairs of mandibular

positions in the three planes of space. These tasks include

discrimination of pairs of positions in the vertical dimension

(interdental thickness discrimination), in the lateral dimen-

sion (discrimination of lateral mandibular positions), and in

the anterior-posterior dimension (discrimination of anterior-

posterior mandibular positions).

The fifth and final perceptual task required subjects

to make judgements between pairs of weighted capsules placed

between the maxillary and mandibular incisors. This task was

included in an attempt to either implicate or rule out the

sensory mechanism of the TMJ as having a role in interdental

weight discrimination. Tasks were presented in a random order.


Duplication of an interdental space

This task required each subject to reproduce an arbi-

trarily determined, comfortable open mouth position somewhere

between the closed or physiologic rest position and a maximum

open mouth position (Thilander, 1961). The amount of mouth

opening was determined by measuring the distance between the

upper and lower central incisors with a plastic ruler.

Measurements were taken to the nearest millimeter. The ruler

was shaped so that one end would fit over the incisal edge of

the lower incisors to insure standard measurement conditions.

Each subject was instructed to remember the initial mouth

or jaw open position and then to attempt to replicate this

same position ten times in close








succession. The distance between the upper and lower central

incisors was measured and recorded by the examiner for each

of the ten subsequent trials. The subject was not informed

as to the accuracy of his responses.


Interdental thickness discrimination

This task required each subject to make judgements

concerning the thickness of blocks placed in pairs, one at

a time, between the maxillary and mandibular central incisors.

The instrumentation used in this task, which was developed

by Williams and LaPointe (1972), is illustrated in Figure

8 and consists of 21 acrylic blocks, each 4.5 cm long by

1.5 cm wide. The thickness of the blocks varies in 1 mm

increments and ranges from 10 to 25 mm. In performing this

task, each subject was asked to judge whether the second

block of each pair was "the same," "thicker," or "thinner"

than the first block of the pair. The first block in

each pair presentation was considered the "standard" and was

always 10 mm thick. The second block presented in each pair

was a different thickness. A modified "method of limits"

procedure, with two ascending runs, was used to arrive at

each subject's difference limen. A "run" was defined as

the presentation to the subject of as many different pairs

of blocks as necessary until two consecutive correct judge-

ments were made.


Discrimination of lateral mandibular positioning

Each subject's ability to discriminate differences in







































Figure 8
Acrylic Blocks for Assessing
Interdental Thickness Discrimination







































Figure 9
Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination








mandibular position lateral to a midline position was

assessed using an instrument designed and developed by

Williams and LaPointe (1973). This instrument is illustrated

in Figure 9. The device consists of two interlocked, sliding

plates that are adjustable in one-half millimeter increments

by means of a thumb screw which allows for controlling the

position of one plate in relation to the other. The v-shaped

wedge on the upper plate was positioned in the space between

the two maxillary incisors. The subject then moved his jaw

about until the lower plate seated between the space of the

two mandibular incisors. This task required the subject to

make judgements concerning the lateral position of his lower

jaw as determined by the positions of the lower wedge, which

were presented to him, in pairs, one at a time. Each subject

was asked to judge whether the second position was "the same,"

"to the left," or "to the right" of the first position. The

first position, considered the "standard," was always that

position where upper and lower wedges were in a vertical line.

The second position in each pair was a different position

either to the left or to the right of midline. Again, a

modified "method of limits" procedure, with two ascending runs,

was used to arrive at each subject's difference limen in a left

or right direction. As in the interdental thickness task, a
"run" was defined as the presentation of as many different

pairs of wedge settings as necessary until two consecutive

judgements were made.








Discrimination of anterior-posterior mandibular positions

Each subject's ability to discriminate between mandibular

positions anterior to a position in which the maxillary and the

mandibular incisors are in a vertical line was assessed

utilizing the same instrument which was used in assessing

lateral discrimination ability. For the anterior-posterior

task, however, the inverted v-shaped wedge on the upper plate

(shown at left of instrument in Figure 9) was placed over

the maxillary incisors seated in the wedge on the lower plate.

This task required the subject to make judgements concerning

the anterior position of his jaw as determined by the positions

of the lower wedge which were presented to him in pairs, one at

a time. Each subject was asked to judge whether the second

position of each pair was "the same," "forward," or "backward"

compared to the first position. The first position, again

considered the "standard," was always that position where the

upper and lower wedges were in a vertical line. The second

position of each pair was a different position anterior to the

first. The same modified "method of limits" procedure, with

ascending runs, was used to determine each suject's threshold

of detecting differences in jaw positions in the anterior

direction. A "run" was defined as it had been for the pre-

ceding tasks.


Interdental weight discrimination

This task was used to assess each subject's ability to

discriminate between pairs of weighted capsules. The task

utilized the instrumentation shown in Figure 10. The







































Figure 10
Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination








instrumentation was developed by Williams and LaPointe (1972)

and uses 21 capsules ranging in weight from 5 to 25 grams.

This task required each subject to make judgements between

pairs of weighted capsules which were presented, one at a time,

between the maxillary and the mandibular central incisors.

Each subject was asked to judge whether the second of each

pair of capsules was "the same," "heavier," or "lighter" than

the first capsule. The first capsule was always the "standard"

weight of 5 grams. The second capsule of each pair was always

heavier than the first. A modified "method of limits," with

two ascending runs, was used to arrive at each subject's

difference limen. A "run" was defined as for the previous

perceptual tasks.


Nonspeech Oral Movements

Tasks of nonspeech oral movement were included in the

study since evidence suggests that the neurological process

governing speech and nonspeech oral movements are dissimilar.

Hixon and Hardy (1964) suggested that speech movements may be

the result of automatic, programmed motor patterns, while less

practiced nonspeech oral movements, such as repetitive raising

the tongue to and dropping it from the alveolar ridge, would

require voluntary, concentrated motor movements.

Two nonspeech oral movements were used on this study to

examine the role of the sensory mechanism of the TMJ for

regulating mandibular movement and positioning for nonspeech

activities. These tasks required each subject to: 1) elevate

the tongue tip up against the alveolar ridge and to drop it








from this contact and 2) elevate the dorsum of the tongue up

against the roof of the mouth and drop it from this contact.

Each of these two tasks were performed three times by each

subject.


Speech Sample

A primary purpose of the study was assessment of the

effects of the experimental conditions on mandibular posi-

tion during speech production. A speech sample was devel-

oped which provided varied amounts of lingual-palatal con-

tact, required a wide range of mandibular positioning, and

contained a wide range of speech sounds. The speech sample

required each subject to produce a series of diphthongs, a

series of vowel-consonant-vowel (VCV) combinations, as well

as a sample of connected speech.


Vowel-consonant-vowels: /isi/, o/s-./, /iki/, and /lkka/

The VCV combinations were formed using consonants and
vowels that have been reported to require a wide range of

mandibular placements. Kent and Moll (1972) and Owens (1973)

have shown that front consonants, such as the /s/, and high

vowels, such as /i/, are produced with a more elevated man-

dibular placement than are the back consonants, such as /k/

and the low vowels, such as /a/. Therefore, the following

VCV combinations were developed: /isi/, /asoa, /iki/, and

/akLk/. Each of the VCV combinations were spoken three times

by each subject for three of the conditions. Subjects were

instructed to put the same stress on the second vowel as

they did on the first one.








Diphthongs: /al/, /eI/, /aU/, /oI/

A diphthong has been defined by Wise (1957) as two

vowels pronounced in a quick, unbroken succession within a

syllable, and connected by a gliding series of unrelated

sounds. Four diphthongs were included in the speech sample

because of their unique arrangement consisting of a low or

mid vowel and a high vowel. Production of these diphthongs

requires considerable mandibular and lingual movement with

minimal lingual-palatal contact. The diphthongs used in this

study were: /al/, as in the word "high," /el/, as in the word

"hay," /3I/, as in the word "hoist," and /aU/, as in the word

"how." As for production of the VCV combinations, each of the

diphthongs were spoken three times by each subject for each of

the three conditions.


Connected speech

The sentence "In the evening Connie watches TV with me."

was selected as a representative sample of ongoing speech. It

contains a distribution of front and back consonants, such as

/t/ and /k/, as well as vowels which represent the extremes of

the vowel triangle, such as /i/ and /-/. Each subject was

instructed to repeat the sentence in their usual speaking

manner relative to such factors as intensity, duration, and

inflectional patterns.


Experimental Procedures
Two experimental conditions were developed for this

study. The experimental conditions were: 1) unilateral anes-
thetization of the right auriculotemporal nerve (innervating

the right TMJ)








and 2) anesthetization of the right auriculotemporal nerve

with a painless pressure administered to the contralateral

TMJ capsule. All of the experimental tasks outlined were

performed by each subject under each of the experimental

conditions and under a normal condition where the subject

received neither anesthesia nor pressure stimulus.


Anesthetization

Anesthetization of the auriculotemporal nerve was

performed and observed by Parker E. Mahan, D.D.S., College

of Dentistry, University of Florida. A 2% xylocaine solution,

with a vaso-constrictor, was injected into the nerve as it

ascends near the posterior border of the mandible. Approx-

imately 0.8 cc of xylocaine was used for each anesthetization.

The anesthetized state was maintained for approximately

three to four hours as evidenced by subject report. All

subjects received the anesthesia on their right side.


Pressure

The second experimental condition involved applying

pressure to the left TMJ capsule while the right TMJ was

anesthetized. The pressure device, illustrated in Figure 11,

incorporates a calibrated, spring-loaded disc 2.5 cm in

diameter. The design allows for monitoring the amount of

force that the disc exerts against the TMJ capsule. The

amount of pressure, acknowledged as less than painful

by each subject, varied from 1.0 to 2.0 pounds. The mean








































Figure 11
Cephalostat and Pressure Device








amount of pressure used was 1.8 pounds.

The pressure device was attached to a cephalostat,

which is also illustrated in Figure 11. The cephalostat

was designed to fit around the subject's head, in a halo

fashion, with four points of contact for stabilization, two

anteriorly and two posteriorly. This design prevented any

interference with the movement of the muscles of mastica-

tion. Both the cephalostat and the pressure device were

designed by the author and were constructed in the Bioinstru-

ment Shop at Shands Teaching Hospital, University of Florida.



Filming Procedures

The nonspeech oral movements and speech tasks were re-

corded cinefluoroscopically. A 16 mm Auricon Cine II Voice

camera mounted on a Picker fluoroscope, with a five inch

image intensifier, was used to obtain the cinefluorographic

films of the speech structures during the production of the

nonspeech oral movements and during production of the speech

sample. Eastman Kodak Double X film (type 7222) with a mag-

netic sound strip was used. The filming speed was 24 frames

per second. The film was processed in a Smith-Picker auto-

matic processor. The radiographic and the film processing

equipment are located in Shands Teaching Hospital, University

of Florida.

Each subject was filmed in a upright sitting position

with his head positioned and stabilized in the cephalostat.

A radiopaque, stainless steel ruler, with holes drilled into








it at centimeter intervals, was inserted in the subject's

mouth at the initiation of filming. It was, therefore, pos-

sible to project the filmed image at some known magnification

relative to life size.


Procedures For Film Data Collection


Measuring Apparatus

A Lafayette Analyzer 16 mm Projector was used to analyze

the cinefluorographic films. The Lafayette Projector is cap-

able of frame by frame oroiection or continuous projection at

variable speeds. The image of the subject and the ruler was

projected one and one half times larger than life size by ad-

justing the position of the perpendicularly mounted tracing

board relative to the projector. It was necessary to project

the image to this size because of the limitation of the pro-

jector to focus the image any smaller. All of the measure-

ments were corrected to life size following compilation of

the data.


Construction of Template

Prior to measurement, a template was constructed from

the projected image of the initial frame depicting the mid-

line structures. The midline structures included the hard

palate from the anterior nasal spine to the posterior nasal

spine, the upper central incisors, and the alveolar ridge.

These structures were used for constucting lines of reference

as well as for adjusting the template to the frame to be mea-

sured in order to insure accuracy of measurement.








Planes of Reference

Three lines of reference were constructed on the template

for measurement of the vertical and horizontal positions of

the mandible. Figure 12 illustrates these lines of reference.

Line PP. This line defines the palatal plane which is a

standard reference line in cephalometric studies. This line

is defined as a line which passes through the midpoint of the

anterior nasal spine and the midpoint of the posterior nasal

spine. This line was chosen because it approximates the

horizontal plane and provides a reference line for measuring

the vertical position of the mandible.

Line AB. This line represents a plane which is parallel

to the palatal plane and is tangent to the most inferior point

of the central maxillary incisor. This line also approximates

a horizontal plane and allows for easier measuring of vertical

jaw positions than would making measurements from the central

mandibular incisor to the palatal plane. The vertical posi-

tion of the mandible was recorded relative to this line.

Line CD. This line represents a plane which is perpen-

dicular to the palatal plane. This line passes through the

most inferior midpoint of the upper central incisor. This line

approximates a vertical plane and serves as the reference for

measuring the horizontal positioning of the mandible.


Definition of Measurements

The vertical and horizontal positions of the mandible

were measured relative to the planes of reference defined











































Measurement of vertical mandibular displacement noted
in a downward or positive (+) direction.

Measurement of vertical mandibular displacement noted
in an upward or negative (-) direction.

Measurement of horizontal mandibular displacement noted
in a backward or positive (+) direction.

Measurement of horizontal mandibular displacement noted
in a forward or negative (-) direction.

Figure 12
Defined Measurements of Mandibular Displacement
and Associated Positive and Negative Values








above and illustrated in Figure 12. The following discussion

defines the vertical and horizontal measurements of mandibular

displacement.

Measurement of vertical mandibular position. Measurement

of the vertical position of the mandible was defined as the

perpendicular distance between the superior tip of the mandi-

bular central incisor and line AB. A positive value was

assigned when the tip of the lower central incisor was below

AB and a negative value was recorded when the tip of the

incisor was above line AB.

Measurement of horizontal mandibular position. The

horizontal position of the mandible was defined as the perpen-

dicular distance between the tip of the mandibular incisor

and line CD. Positive values were assigned when the position

of the tip of incisor was posterior to the line CD. Negative

values were assigned when the tip of the incisor was observed

to be in front of line CD.


Identification of Frames Measured for the Speech and Nonspeech
Tasks

The initial and the final frames of each of the nonspeech

and the speech tasks were located and marked. The segment of

film portraying the production of each of the tasks was then

numbered consecutively, frame by frame, for ease of identifi-

cation.


Nonspeech tasks

Tongue tip to alveolar ridge. The frame identified as the

initiation of this nonspeech task of elevating the tongue tip








to the alveolar ridge was defined as that frame showing the

tongue first making contact with the alveolar ridge. The

final frame for that task sequence was identified as that frame

showing the tongue in its lowest position just prior to its

elevation for the beginning of the next trial. In addition,

a third frame was identified in which the tongue was observed

to be releasing contact from the alveolar ridge. It was,

therefore, possible to define the position of the mandible at

the beginning and at the end of the three trials for this

task, as well as the range of mandibular movement throughout

each trial. The length of time (in number of frames) for the

completion of each trial and the length of time of lingual

palatal contact was defined also.

Tongue dorsum to palate. The frame identified as the ini-

tiation of this nonspeech act was defined as that frame showing

the tongue contacting the palate approximately at the posterior

nasal spine. The frame showing the tongue in its lowest posi-

tion just prior to elevation for the beginning of the following

trial was defined as the final frame in each trial. A third

frame showing the tongue releasing contact from the palate

was also identified. Again, it was possible to define the

position of the mandible at the initiation and completion of

each trial for this task and the range of mandibular movement

through each trial. The length of time for the completion of

each trial and the amount of time during which the tongue

was in contact with the palate was recorded also.








Vowel-consonant-vowels: /isi/, /asa/, /iki/, and /aka/

Those frames identified as the beginning and the end of

each VCV sequence were defined in terms of optimal lingual

placement for the production of the two vowels /i/ and /a/.

The frame showing the vowel /i/ as it occurred in the

initial position of the VCV sequence was defined as that frame

picturing the tongue in its highest position prior to its

movement for the production of the following consonant. The

frame showing the vowel /a/ as it occurred in the initial

position was defined as that frame showing the lowest tongue

position prior to its movement for the production of the

following consonant.

The frame showing the vowel /i/ as it occurred in the

final position of the VCV sequence, was defined as that frame

showing the tongue in its highest position prior to its move-

ment to a rest position. The frame showing the vowel /a/, as

it occurred in the final position of the VCV sequence, was

defined as that frame showing the tongue in its lowest position

prior to its movement to a rest position.

In addition to the initial and the final frames of each

trial, those frames depicting the lingual palatal contact

required for consonant production were identified. Thus, it

was possible to define the vertical and the horizontal position

of the mandible at start and finish of each trial as well as

during consonant production. These measurements also provided

the range of mandibular motion throughout each trial. The

length of time for the completion of each trial and the amount

of time required for the production of the consonants and the

vowels were recorded also.








Diphthongs: /al/, /el/, /aU/, and /,I/

The initial and the final frames representing the pro-

duction of each of the diphthongs were identified as those

frames showing optimal tongue or lip placement for the produc-

tion of the respective vowels.

The frames identified as the production of the vowels

/a/, /e/, and /3/ as they occur in the initial positions of
the diphthongs /al/, /el/, and /)I/ respectively were defined

as those frames showing the tongue in its lowest position

prior to elevation for the production of the second vowel in

the diphthong. The frame identified as the production of the

vowel /a/ in the initial position of the diphthong /aU/ was

defined as that frame showing the lip in its lowest position

prior to its elevation for rounding in the production of the

second vowel in the diphthong.

The frames identified as the production of the vowel

/I/ as it occurs in the final position of the diphthongs /aI/,

/el/, and /.I/ were defined as those frames showing the
tongue in its highest position prior to its lowering for the

initiation of the next trial. The frame identified as show-

ing the production of the vowel /U/ as it occurs in the final

position of the diphthong /aU/ was defined as the frame show-

ing the lower lip in its highest position prior to its lowering

for the beginning of the next trial.

It was possible, therefore, to define the vertical and
horizontal position of the mandible at the beginning and at

the end of the production of each trial as well as the range








of mandibular motion through each trial. The length of time

required to complete each trial was recorded also.

Sentence

Seventeen frames depicting the production of seventeen

speech phonemes were selected from the sentence, "In the

evening Connie watches TV with me." The selected phonemes are

represented by the underlined graphemes in the sentence below.

IN TH E E V E N I N G C 0 N NIE W A T C H E S TEE
1 2 3 4 5 6 7 8 10 11 T2

V E E W I T H M E.
T3 14 15 1 6 17

The definitions for identifying these phonemes within the

sentence from cinefluorographic recordings have been described

in detail by Owens (1973) and have been duplicated here for

convenience.

1. The /5/ of "the" was defined as the lingual-dental contact

immediately following the lingual-alveolar contact required

for the production of the phoneme /n/ of "in".

2. The /i/ of "evening" was defined as the highest point of

lingual elevation preceding the labial-dental contact re-

quired for the production of the phoneme /v/ of "evening".
3. The /v/ of "evening" was defined as the labial-dental

contact necessary for its production.

4. The /1/ of "evening" was defined as the part of lingual-

velar contact between the back of the tongue and the velum

while the velum was down.

5. The /k/ of "Connie" was defined by the lingual-velar contact

required for its production while the velum was








closing off the velopharyngeal port.

6. The /,/ of "Connie" was defined as the lowest and most

posterior point of lingual movement preceding the lingual-

alveolar contact required for the production of the phoneme

/n/ of "Connie".

7. The /n/ of "Connie" was defined as the lingual-alveolar

contact required for its production.

8. The /w/ of "watches" was defined by the maximum forward

movement of the lips required for its production,

9. The /a/ of "watches" was defined as the lowest and most

posterior point of lingual movement preceding the lingual

alveolar contact required for the production of the /V /

of the word "watches".

10. The /y/ of "watches" was defined as the lingual-alveolar

(sometimes lingual-palatal) contact required for its pro-

duction while the teeth were closed and the lips pro-

truded slightly.

11. The /t/ of "TV" was defined as the lingual-alveolar con-

tact required for its production.

12. The first /i/ of "Tee Vee" was defined as the highest point

of ligual movement preceding the labial-dental contact re-

quired for the production of the phoneme /v/ of "TV".
13. The /v/ of "TV" was defined as the labial-dental contact

required for its production.

14. The second /i/ of "Tee Vee" was defined as the highest

point of lingual elevation preceding the forward move-

ment of the lips required for the production of the

phoneme /w/ of "with".








15. The /8/ of "with" was defined as the lingual-dental

contact required for its production.

16. The /m/ of "me" was defined as the bilabial contact re-

quired for its production.

17. The /i/ of "me" was defined as the highest point of

lingual elevation following the bilabial contact required

for the production of the phoneme /m/ of "me".

Reliability

Since the author made all measurements, only inter-

measurer reliability was assessed. The vertical and horizontal

measurements were remeasured for forty-five frames. The cor-

relation between the initial and the second measurements was

calculated. A correlation coefficient of .99 was obtained for

the forty-five vertical measurements and a coefficient of .97

was obtained for the forty-five horizontal measurements. These

correlation coefficients are considered to be within acceptable

limits.













CHAPTER FOUR
RESULTS


The results of this study will be presented relative to

1) descriptive analysis of the data and 2) statistical analysis

of differences between the experimental and control conditions.

Descriptive analysis was completed for the five perceptual mea-

sures and the connected speech passage. Measurements of cen-

tral tendency and the dispersion of performance on each of the

test measures accompanies a narrative description of the re-

sults. Statistical analysis was completed for ten test mea-

sures including the two nonspeech tasks, the four tasks of

diphthong production, and the four tasks of vowel-consonant-

vowel production. The statistical analysis included an ana-

lysis of repeated measures and the Newman-Keuls analysis. A

more detailed description of the statistical procedures fol-

lows the presentation of the results for the perceptual mea-

sures and sentence production.


Analysis of Perceptual Tasks and Connected Speech

Perceptual Measures

Duplication of interdental space

This task was included in an attempt to replicate a

portion of Thilander's (1961) study. Table 1 displays subject














Table 1
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Range of Jaw Position for Ten Trials



Condition

Subject Normal Anesthetized Anesthetized and Pressure


3.0 mm

8.0

2.0

11.0


5.0 mm

4.0

6.0

7.0


Means 6.00 mm 5.50 mm

Standard
Deviation 4.24 1.29


3.0 mm

2.0

7.0

4.0


4.00 mm


2.16








performance during attempts to duplicate the standard position

ten times under the three conditions. Included in Table 1 are

means and standard deviations for the group of four subjects.

Anesthesia appeared not to make it more difficult for the

subjects to find the standard jaw opening; the mean for the

normal condition is 6.00 mm, while the mean for the anesthesia

condition is 5.50 mm. However, three subjects (A, B, and D)

of the four found it easier to duplicate the standard position

when a light pressure was applied to the left TMJ. This is

also reflected in a reduced mean performance score for the

pressure condition; X = 4.0 mm.

The mean difference in jaw position from the standard

position, as well as standard deviation, is presented in Table

2. The means obtained for each of the three conditions sug-

gest that neither the anesthesia nor the anesthesia and pres-

sure had an affect on the ability of the subjects to dupli-

cate the standard. The means vary from a 3.25 mm for the

anesthesia and pressure condition to a 3.65 mm for the normal

condition.

Analysis of individual subject means presents somewhat

conflicting results. The ability of subjects A and C to du-

plicate the standard was impaired somewhat by the anesthesia

condition. However, performance was improved by pressure to

the opposite TMJ only for subject A. Subject D's performance

also was improved by pressure, however, his performance under

anesthesia was better than under the control condition. More-

over, the performance of subjects A and C was impaired by














Table 2
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard



Condition


Normal Anesthetized ed and Pressure


2.4 mm


Means

Standard
Deviation


4.4 mm


3.65 mm 3.52 mm


0.8 mm


3.25 mm


2.83


Subject


Subject_ __ __ _


~


0.96








anesthesia compared to normal and the performance of A and D

was improved by pressure compared to anesthesia. Only subject

A fit the profile of performance presented by Thilander of

impaired performance under anesthesia condition and improved

under the pressure condition.

Interdental thickness discrimination

Individual subject performance scores for each of the

two runs are presented for the task of interdental thickness

discrimination in Table 3. The mean amount of thickness re-

quired for two consecutive correct descriminations is greater

for anesthesia condition (1.75 mm) than for the normal con-

dition (1.38 mm). Subjects required an average of 1.50 mm

difference under the pressure condition. This suggests that

some mild disruption occurred due to the anesthesia and some

recovery of discriminative abilities occurred with the ap-

plication of pressure. Further analysis (Table 4) revealed

that 100% correct discrimination occurred under the normal

condition and pressure condition when the difference in

block size was 2 mm. However, 4 mm were required under the

anesthesia condition in order to obtain 100 % discrimination.


Discrimination of lateral mandibular position

Each subject's ability to discriminate between pairs of

lateral positions of the mandible was assessed to the left of

and to the right of midline, No difference in subjects' per-

formance was observed between the control and anesthesia con-

dition when ability on this task was tested to the left of














Table 3
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination



Condition
Subject Trial Normal Anesthetized Anesthetized and Pressure


A 1)

2)

B 1)

2)

C 1)

2)

D 1)

2)






Means

Standard
Deviation


1.0 mm

1.0

1.0

2.0

2.0

1.0

1.0

2.0


2.0 mm

1.0

1.0

1.0

1.0

2.0

2.0

4.0


1.38 mm 1.75 mm


1.0 mm

1.0

1.0

1.0

2.0

2.0

2.0

2.0


1.50 mm


0.52 1 .04 0.53


0.52


1.04


0.53





71






Table 4
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination


Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure

10 mm 11 mm 62.5% 57% 50%

10 mm 12 mm 100 87.5 100

10 mm 13 mm 100 87.5 100

10 mm 14 mm 100 100 100








midline. (Table 5: X = 1.69 mm and X = 1.62 mm, respectively)

Subjects, as a group, found it easier to discriminate between

positions to the left of midline under the pressure condition

(X = 1.25 mm).

The mean percent of correct subject responses per

stimulus pairs for jaw positions to the left of midline are

presented in Table 6. These data illustrate that subject

performance reached 100% for the normal and anesthesia con-

ditions when the difference between the pair of positions

reached 2.5 mm. Only 2.0 mm difference was necessary for

100% performance under the pressure condition. Moreover, the

group means presented in Table 5 and the mean percent of cor-

rect subject responses presented in Table 6 for discrimina-

tion of jaw positions to the left of midline suggest that

anesthesia had no effect on the subject's discriminative

abilities while pressure to the TMJ, contralateral to the

anesthesia, enhanced performance somewhat. It should be

noted that pressure was always applied to left TMJ capsule,

or, for this task, to the side of jaw movement.

Subject performance scores, group means, and S.D.'s

are presented in Table 7 for the task of discrimination be-

tween pairs of lateral jaw positions to the right of midline.

The group means presented in Table 7 suggest that this group

of subjects performed most accurately under the normal

condition (X = 1.12 mm) and performed least accurately under

the pressure condition (X = 2.06 mm). The group mean for the

anesthesia condition (X = 1.45 mm) fell between the two other














Table 5
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination for the Left


Condition

Subject Trial Normal Anesthetized Anesthetized and Pressure

A 1) 3.0 mm 1.0 mm 1.0 mm

2) 2.0 1.5 1.5

B 1) 0.5 1.0 0.5

2) 1.5 1.0 2.0

C 1) 1.0 1.5 0.5

2) 1.0 1.0 0.5

D 1) 2.0 2.5 1.5

2) 2.5 3.5 2.5






Means 1.69 mm 1.62 mm 1.25 mm

Standard
Deviation 0.84 0.92 0.76













Table 6
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Jaw Position Discrimination to the Left


Condition

stimulus Pairs Normal Anesthetized Anesthetized and Pressure

mm 0.5 mm 37.5% 87.5% 37.5%

mm 1.0 mm 50 62.5 75

mm 1.5 mm 50 75 75


0 mm 2.0 mm

0 mm 2.5 mm

0 mm 3.0 mm

0 mm 3.5 mm

0 mm 4.0 mm

0 mm 4.5 mm

0 mm 5.0 mm


75

87.5

100

100

100

100

100


100

87.5

100

100

100

100

100


87.5

100

100

100

100

100

100


St

0

0

0














Table 7
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Right


Condition

Subject Trial Normal Anesthetized Anesthetized and Pressure


A 1)

2)

B 1)

2)

C 1)

2)

D 1)

2)


Means


1.5 mm

1.0

2.0

1.0

1.0

0.5

0.5

1.5


2.5 mm

1.0

1.0

1.5

0.5

0.5

1.5

3.0


1.12 mm 1.45 mm


2.5 mm

1.0

2.0

2.0

1.0

0.5

4.5

3.0


2.06 mm


Standard
Deviation 0.52


0.23


0.74













Table 8
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Mandibular Position Discrimination to
the Right


Stimulus Pairs


mm 0.5 mm

mm 1.0 mm

mm 1.5 mm

mm 2.0 mm

mm 2.5 mm

mm 3.0 mm

mm 3.5 mm

mm 4.0 mm

mm 4.5 mm

mm 5.0 mm


Condition

Normal Anesthetized Anesthetized and Pressure


37.5%

75

87.5

100

100

100

100

100

100

100


25%

50

87.5

87.5

87.5

100

100

100

100

100


25%

50

50

75

75

87.5

100

87.5

100

100








condition means.

Table 8 presents the mean percent of correct subject

responses per stimulus pair for the task of lateral jaw posi-

tion discrimination to the right of midline. These data

demonstrate also that subjects' ability to perceive differ-

ences in positions to the right of midline was hampered by

the application of pressure to the left TMJ capsule.


Anterior-posterior jaw position discrimination

Table 9 presents the individual and group performance

scores for anterior-posterior jaw position discrimination.

The group means illustrate that the subjects'; performance

was equal for the anesthesia and the pressure conditions.

Table 10 presents the mean percent of correct subject re-

sponses per stimulus pair for this task. Subjects per-

formed less accurately in discrimination between pairs of

anterior-posterior jaw positions under the normal control

condition than under the experimental conditions. 100%

performance was attained when the difference between pairs

was 1.0 mm for the anesthesia and the pressure conditions.

For the normal condition, 100% performance was not reached

until the difference between pairs of jaw positions was

2.5 mm.


Discrimination of interdental weights

Individual and group performance scores for the task

of interdental weight discrimination can be found in Table

11. The anesthesia condition had little effect on subjects'













Table 9
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination


Condition

Subject Trial Normal Anesthetized Anesthetized and Pressure

A 1) 1.5 mm 0.5 mm 0.5 mm

2) 2.5 0.5 0.5

B 1) 0.5 0.5 0.5

2) 0.5 0.5 1.0

C 1) 0.5 0.5 0.5

2) 0.5 1.0 1.0

D 1) 0.5 1.0 1.0

2) 2.0 0.5 0.5






Means 1.06 mm 0.62 mm 0.68 mm

Standard
Deviation 0.82 0.94 0.23













Table 10
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Anterior-Posterior Jaw Positions


Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure

0 mm 0.5 mm 87.5% 75% 75%

0 mm 1.0 mm 100 100 100

0 mm 1.5 mm 75 100 100

0 mm 2.0 mm 87.5 100 100

0 mm 2.5 mm 100 100 100

0 mm 3.0 mm 100 100 100














Table 11
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination


Condition

Subject Trial Normal Anesthetized Anesthetized and Pressure

A 1) 5.0 gms 14.0 gms 5.0 gms

2) 6.0 6.0 5.0

B 1) 13.0 4.0 11.0

2) 11.0 4.0 12.0

C 1) 7.0 5.0 2.0

2) 8.0 6.0 6.0

D 1) 4.0 6.0 12.0

2) 7.0 12.0 16.0






Means 7.62 gms 7.12 gms 8.62 gms

Standard
Deviation 3.01 3.75 4.47








ability to discriminate between paired weights. Group means

are 7.62 gms for the normal condition and 7.12 gms for the

anesthesia condition. Pressure appeared to make discrimina-

tion between interdental weights more difficult. The mean

difference required was 8.62 gms for this condition.


Summary: perceptual measures

Anesthesia to the right auriculotemporal nerve appeared

to have a mild disruptive influence on this group of subjects'

abilities to discriminate between the thickness of pairs of

blocks placed interdentally. Pressure to the contralateral

(left) TMJ capsule restored discriminative ability somewhat

(Tables 3 and 4).

Pressure to the left TMJ appeared to enhance subject

performance of tasks where anesthesia had no disruptive

effects. These tasks include Thilander's task of replicating

a standard interdental space ten times (Table 1), discrimi-

nation between pairs of lateral jaw positions to the left of

midline (Table 5), and discrimination between pairs of

anterior-posterior jaw positions (Table 9). On the other

hand, pressure to the left TMJ capsule appeared to be dis-

ruptive of subjects' ability to discriminate between pairs

of lateral jaw positions to the right of midline (Tables 7

and 8). Pressure appeared to have a disruptive effect on

subjects' ability to discriminate between the weights of

capsule pairs placed between the incisors (Table 11). Neither

of the experimental conditions appeared to influence the

subjects' performance on Thilander's task of duplicating a

standard jaw position when that task ia analyzed by the mean








difference of jaw positions from the standard position.


Sentence

Figure 13 combines a tabular and graphic representation

of the vertical jaw displacement (N = 4) for the seventeen

phonemes under each of the three conditions. The mean, range,

and standard deviation are entered below each phoneme. Figure

14 presents the complimentary data for horizontal mandibular

displacement. Since measures from the film were made at one

and one-half life size (Chapter Two), all measurement values

were reduced by one-third to achieve absolute values. Statis-

tical significance could not be assessed due to the small

number of observations.

Figure 13 demonstrates that similar vertical patterns of

jaw movement are maintained under each of the test conditions.

The most closed jaw postures are observed for the /tJ / in

"watches" and the /t/ in "TV." The greatest amount of mandi-

bular displacement is observed for the /a/ in "Connie" and the

/a/ in "watches." These observations are compatible with

previous research findings (Kent and Moll, 1972 and Owens,

1973).

In general, vertical jaw displacement was greatest for

the anesthesia condition and least for the pressure condition.

Under anesthesia, jaw displacement was equal to normal for the

initial speech sounds in the sentence. As the amount of re-

quired displacement increased for the open sounds in "Connie"

and "watches," the jaw opened more for the anesthesia condi-

tion than for the normal condition. As the



























Phoneme A 1 v
IN T HE E V
Normal -
Mean 3.35 5.19 3.35
Range 4.69 5.36 5.36
Std.Dev. 2.12 2.34 2.44

Anesthetized
Mean 3.52 5.02 3.52
Range 6.03 4.69 3.35
Std.Dev. 2.59 2.08 1.76
Anesthetized and Pressure
Mean 2.85 4.36 2.85
Range 5.36 5.36 4.69
Std.Dev. 2.34 2.47 2.28


3.52
6.03
2.75


Co n w f t I v 1 8 m i
C 0 N N I E W ATC E S TEE V E EW I T H M E
7.37 5.53 5.70 7.70 0.84 -.34 2.18 1.67 3.02 3.52 3.35 3.5
9.38 8.04 8.71 8.04 2.68 3.35 4.02 3.35 4.69 5.36 4.69 6.7
4.17 3.92 4.11 3.52 1.38 1.39 1.84 1.59 1.93 2.64 2.12 2.S


4.52 4.36 8.21 6.70 5.19 6.36 0.34 -.34 3.68 2.85 3.68 4.52
6.70 5.36 8.04 4.02 7.37 8.71 3.35 4.02 3.35 3.35 4.69 4.02
2.81 2.28 3.64 2.12 3.34 3.89 1.59 1.77 1.59 1.58 1.93 2.14


2.8513.68
4.02 4.69
1.84 1.93


6.03 4.52 3.68 4.69 -.84 -.00 1.68 1.34 1.84
4.02 2.60 4.02 5.36 3.35 4.69 4.02 2.68 4.69
1.97 1.38 1.77 2.25 1.58 2.08 2.01 1.54 2.27


4.19
3.35
1.76


2.85 2.34
3.35 4.02
1.70 2.01


Figure 13
Means, Ranges and S.D.'s of Vertical Jaw Positions Under Three
Conditions for 17 Sounds Selectea From a Connected Apeech Sample (N-4)








amount of required jaw displacement decreased for the conso-

nants at the end of "watches" and in "Tee Vee", the jaw began

to close sooner for anesthesia. Jaw displacement for the

/tf/ in "watches" and /t/ in "Tee Vee" appeared equivalent

for the two conditions. As the amount of required jaw dis-

placement increased for the open sounds at the end of the

passage, the jaw opened more for the normal condition. This

is interpreted as over-shooting of the target position for

the production of open speech sounds.

On the other hand, pressure appeared to reduce vertical

displacement. It appeared to do so consistently over all the

speech elements in the speech sample, both open and closed,

The pattern of jaw posturing in the horizontal dimen-

sion is similar also for the three conditions, Figure 14.

The most anterior jaw postures are observed for the /tf/ in

"watches" and the /t/ in "Tee Vee". The most retruded pos-

tures are observed for the /a/ and /n/ in "Connie" and the

/a/ in "watches". These observations, again, are compatible

with previous research findings (Kent and Moll, 1972 and

Owens, 1973). The findings also support observations of the

hinge action of the mandible. That is, the greater the

vertical displacement of the mandible, the more retruded the

structure will be.

The effects of anesthesia and pressure observed in the

vertical dimensions are not readily apparent in the horizontal

plane. The path of jaw movement for any one condition inter-

sects the others.













6
E E
WE
E 5-
CC
C-- 4



S2-
o:
4.-
0
0 0

Phoneme
I
Normal -
Mean
Range
Std.Dev.


Pressure
.69 4.0
3.35 2.68
1.85 1.22


5.02 4.69 3.52 4.19 2.18 2.01
3.35 4.02 4.02 4.02 4.02 4.02
1.59 1.81 1.76 1.76 1.77 1.73


SE E V E I H M E
S TE E V EE EW I T H M E


1.84 2.68 3.02
2.01 2.68 2.68
1.00 1.22 1.59


2.34 2.84 3.02
2.68 3.35 4.02
1.16 1.48 1.77


3.68 4.36
2.68 2.01
1.28 1.16


4.36 4.36 4.86
2.01 2.68 2.35
1.16 1.28 1.48


4.02 4.02 3.86 4.86
4.02 2.68 3.35 2.68
1.73 1.09 1.38 1.14


Figure 14
Means, Ranges and S.D.'s of Horizontal Jaw Positions Under Three
Conditions for 17 Sounds Selected From a Connected Speech Sample (N-4)


a i 6 L n W L j
N T HE E V E N IN G C 0 N NI E W AT C H E

4.52 4.52 3.35 4.36 4.02 4.02 4.02 4.19 4.36 3.02
3.35 3.35 3.35 2.68 2.68 4.69 4.02 2.01 4.02 4.69
1.76 1.76 1.64 1.28 1.22 1.97 1.81 0.84 1.73 2.08

ed --
4.19 3.68 3.18 4.19 4.36 5.19 5.02 4.19 4.69 3.02
3.35 2.68 2.68 2.01 2.01 3.35 3.35 2.68 3.35 4.02
1.48 1.16 1.38 0.84 0.86 1.38 1.39 1.14 1.64 1.59


Anesthetized
Mean
Range
Std.Dev.

Anesthetized
Mean
Range
Std.Dev.


ed an,
4.86
3.35
1.48








Analysis of Speech Tasks and Nonspeech Oral Movements


The measurements of jaw position obtained from the pro-

jected cinefluorographic frames (as outlined in Chapter Two)

have been summarized relative to five parameters of mandibu-

lar activity for the ten tasks. These parameters are: verti-

cal jaw displacement, horizontal jaw displacement, range of

vertical jaw movement, range of horizontal jaw movement, and

duration or length of production. For each of these five

parameters, measurements were recorded to represent mandibu-

lar activity throughout each task. These data were then sub-

jected to descriptive analysis, that is, mean and standard

deviation and to a test of statistical significance based

upon the analysis of a repeated measures design. The results

of the descriptive analysis and a summary of the analysis of

repeated measures with the mean square, sum of squares, de-

grees of freedom, and F statistic are presented in the ap-

pendix. An F value was considered significant when p4.05.

In the repeated measures design, each subject is ob-

served under each of the test conditions. This study repre-

sents a single factor repeated measures design where there

are three levels to the factor. Those levels are three test

conditions, that is, control, anesthesia, and anesthesia-

pressure.

The analysis of repeated measures provides an analysis

of variance in that the mean score for each condition is

compared with every other mean score. The analysis provides








a test of the statistical hypothesis (null hyphthesis),

Ho: all test condition means are equal. The alternate

hypothesis, H1 states that at least one pair of condi-

tion means differ significantly.

In order to determine between which pair of means

statistical significance exists, the Newman-Keuls Procedure

(Keppel, 1973) was utilized as a second step in the statis-

tical analysis. This procedure allows for multiple com-

parisons of the test condition means and indicates between

which pairs a statistical significance exists. A summary

of the Newman Keuls analysis, that is, the paired condi-

tion values, are presented for each of the ten tasks ana-

lyzed statistically, Tables 12 through 21.

The values for vertical and horizontal displacement

and the values for the range of motion are presented in

millimeters. The values for duration of production are

presented in number of frames. At a filming rate of 24

frames per second, the time between each frame is 40 milli-

seconds.


Nonspeech Oral Movements


Elevation of tongue tip

The amount of vertical mandibular displacement was

measured at three points during the movement, requiring

each subject to elevate his tongue tip. As listed in

Table 12, these measurements of vertical jaw displacement

were taken when the tongue contacted the alveolar ridge,










Table
Results of Newman
Condition Pairs
of Tongue Tip


12
Keuls Analysis:
for Measures
Elevation


Measures


Condition Pairs


Vertical Displacement
Tongue Contact
Tongue Release
Lowest Tongue

Horizontal Displacement
Tongue Contact
Tongue Release
Lowest Tongue

Range of Vertical Movement
Tongue Contact to Lowest
Tongue
Tongue Contact to Tongue
Release
Tongue Release to Lowest
Tongue


Range of Horizontal Movement
Tongue Contact to Lowest
Tongue
Tongue Contact to Tongue
Release
Tongue Release to Lowest
Tongue

Duration of Production
Tongue Contact to Lowest
Tongue
Tongue Contact to Tongue
Release
Tongue Release to Lowest
Tongue

p<.05


Normal/
Anesthesia
10.45/10.72
10.92/10.38
12.80/13.00


6.28/6.62
6.36/6.36
6.77/6.97


Normal/
Anesthesia-
Pressure
10.45/7.97*
10.92/7.24*
12.80/9.31*


6.28/6.12
6.36/5.86
6.77/6.28


2.51/2.26 2.51/2.34

1.17/1.51 1.17/1.43

2.43/2.68 2.43/2.60



0.34/0.67 0.34/0.84

0.59/0.76 0.59/0.84

0.67/1.09 0.67/0.92


Anesthesia/
Anesthesia-
Pressure
10.72/7.97
10.38/7.24*
13.00/9.31*


6.62/6.12
6.36/5.86
6.97/6.28



2.26/2.34

1.51/1.43

2.68/2.60



0.67/0.84

0.76/0.84

1.09/0.92


20.50/25.50 20.50/24.63 25.50/24.63

10.00/14.63*10.00/12.75 14.63/12.75

10.50/10.88 10.50/11.88 10.88/11.88


~








when the tongue just released contact with the alveolar

ridge, and when the tongue was in its lowest posture prior

to elevation for the following trial. Analysis of these

three vertical measures revealed that no significant dif-

ferences existed between the control and the anesthesia

condition, Table 12. However, further analysis revealed

that the vertical displacement of the jaw was reduced

significantly (p<.05) by the application of a light pres-

sure. The amount of horizontal displacement, measured at

these same three points, was not significantly altered under

either of the experimental conditions.

The range of mandibular movement in the vertical and

horizontal planes was calculated between tongue contact with

the alveolar ridge and at the point when the tongue was in

its lowest posture, between the time the tongue contacted the

alveolar ridge and released contact, and between the time the

tongue released contact and assumed its lowest posture. Sta-

tistical analysis of these data revealed no significant dif-

ferences between any of the three pairs of conditions.

Therefore, the range of jaw movement was not altered by anes-

thesia of the right auriculotemporal nerve, nor was the range

of movement altered by a subsequent application of pressure

to the left TMJ capsule.

The amount of time between these same three points was

calculated also. Although the duration of production appeared

increased by the experimental procedures, only the time re-

quired to complete the move from tongue contact to tongue re-

lease was significantly increased by the application of




Full Text
28
painless pressure could normalize the disruptive effects
of unilateral anesthetization of the TMJ capsule when the
pressure was administered to the contralateral joint capsule
The authors theorized that the normalizing effect was the re
sult of activation of nervous elements in the richly inner
vated lateral aspect of the capsule. They also explained
that there may be alteration in the tension of the capsule
requiring less movement than normal to discharge receptors.
Thus, positional changes could be perceived more readily.
Ransjo and Thilander (1963) demonstrated that the func
tion of the TMJ receptors is impaired in TMJ disorders
ascribed to malocclusion, but not dysfunctions of myogenic
origin. Storey (1968) interpreted these results as indi
cating that the masticatory muscles are not involved in per
ception of mandibular position. Ransjo and Thilander (1963)
reported also that in cases of unilateral TMJ dysfunction
again a painless pressure applied to either the intact joint
or both joints would normalize the perception of mandibular
position. The impaired perception of mandibular position in
the malocclusion group could also be normalized by adjusting
and correcting the malocclusion.
Finally, Posselt and Thilander (1965) studied the role
of the TMJ receptors in controlling border movements (extreme
positions) of the mandible. They reported significant in
creases in maximum vertical jaw opening under conditions of
unilateral and bilateral anesthestization of the TMJ capsules
They concluded that the TMJ ligaments participate not only in


140
Table 29 continued
Vowel-Consonant-Vowel /isi/
Summa ry:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure SS
df
MS
F
Thirteen:
A
8.51
9.38
8.71
Time from
B
6.90
7.17
6.50
V-| to V2
C
8.91
6.70
6.50
Mean
8.11
7.75
7.24 8.07
2
4.04
2.081
S.D.
0.61
0.83
0.74
Fourteen:
A
2.90
2.90
2.90
Time from
B
2.68
2.90
4.24
Vt to C
C
2.46
2.23
2.46
Mean
2.68
2.68
3.20 6.89
2
3.44
1 .632
Fifteen :
A
5.58
6.48
5.81
Time from
B
4.24
4.24
2.23
C to V,
C
7.37
4.47
4.02
Mean
5.73
5.06
4.02 29.85
2
14.93
2.843*
S.D.
0.91
0.71
1 .03


71
Table 4
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination
Conditio n
Stimul us
Pai rs
Normal
Anes thetized
Anesthetized and Pressure
10 mm -
11 mm
62.5%
57%
50%
1 0 mm -
1 2 mm
100
87.5
100
1 0 mm -
1 3 mm
100
87.5
100
1 0 mm -
14 mm
100
100
100


26
receptors responsible for mediating the sense of mandibular
position were thought to be housed in the TMJ capsule, muscles
of mastication, or possibly the periodontal ligament
(Thilander, 1961). Studies of interdental thickness discrim
ination comparing the performance of dentulous and edentulous
subjects suggest that the periodontal ligament is not respon
sible for perception of mandibular position (Manly et al., 1952;
Kawamura and Watanabe, 1960; Woodford, 1964; and Siirila and
Laine, 1963). Again, although instrumentation and methodology
differed slightly, several groups of researchers have reported
that the ability to detect thicknesses or difference in thick
nesses does not differ appreciably between dentulous and
edentulous subjects. Discrimination of thickness appears
equally good between natural incisors and natural molars
(Kawamura and Watanabe, 1960 and Siirila and Laine, 1963).
Neither is there any significant difference in perception
threshold when both upper and lower antagonistic teeth are
anesthetized (Siirila and Laine, 1363), nor when the alveolar
mucosa is topically anesthetized (Manly et al. 1 952).
Woodford (1964) found that edentulous subjects performed
equally as well on a task of thickness discrimination with or
without their dentures.
The TMJ's sensory mechanism has been implicated as
performing an active role in mandibular kinesthesia in re
search by Thilander and her colleagues. Thilander (1961)
hypothesized that disrupting the sensory mechanism would impair
perception of mandibular position. She developed a task for


136
Table 28
Diphthong /ol/
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
14.
.07
14.
.74
11 .
,61
Vertical
B
5.
,58
4.
,91
3.
.13
Jaw Posi-
C
5.
,58
7 .
,59
5.
.36
tion for
D
8.
,93
6.
.48
9.
,38
Initial
Mean
8.
,54
8.
43
7.
.37
22,
. 39
2
11
.20
2.
.006
Frame
S.D.
2.
,00
2.
.17
1 .
,92
Two:
A
4.
,24
5.
.81
6,
.92
Horizontal
B
7.
.15
5.
,81
5.
81
Jaw Posi-
C
6.
.70
5.
,81
5 ,
.58
tion for
D
4.
,02
4.
. 24
5.
.14
Inital
Mean
5,
.53
5.
.42
5.
,86
2
.89
2
1
.44
0,
.751
Frame
S.D.
0,
,81
0.
.39
0,
.38
Three:
A
12,
.51
13,
.18
8.
.93
Vertical
B
2,
.23
1 .
, 79
2.
.23
Jaw Posi-
C
0,
.22
1 .
.34
0.
.00
tion for
D
6,
.25
5.
.14
6.
.92
Final
Mean
5,
.30
5.
. 36
4,
.52
11 .
.72
2
5
.86
1 .
.407
Frame
S.D.
2,
.71
2.
.74
2.
.06
Four:
A
4.
.02
5,
.81
5.
.81
Horizontal
B
5 ,
. 36
5.
.14
4,
.91
Jaw Posi-
C
6,
.25
5.
.14
5,
.36
tion for
D
4
.47
5.
.14
6.
,03
Final
Mean
5,
,02
5 .
.31
5.
.53
3,
.39
2
1
.69
0
.855
Frame
S.D.
0.
.49
0,
. 1 7
0.
.25
Five:
A
1 .
. 79
1 .
.79
2.
.68
Range of
B
3,
.57
3,
.12
1 .
.56
Vertical
C
5.
.58
6 ,
.70
5.
.58
Movement
D
2,
.68
1 ,
.56
2.
.46
Mean
3,
.40
3.
.29
3.
.07
1
.56
2
0
CO
0.
.336
S.D.
0.
.81
1 .
,19
0.
.87


98
Summary of diphthong production
The application of a light pressure to the left TMJ
capsule had the effect of reducing the amount of vertical
jaw displacement. The reduction was statistically signifi
cant for those diphthongs requiring greater initial displace
ment: that is /al/, /el/, and / alf/. The range of vertical
movement from the initial to final position was also reduced
significantly by the application of pressure for the diph
thongs / a I / and /ali/. It should be noted that the produc
tion of these diphthongs requires greater initial jaw dis
placement than for the other diphthongs /el/ and loll.
The amount of horizontal displacement for the initial
and final positions of the mandible were not altered by the
experimental procedures. The range of horizontal movement
was altered significantly (reduced) by pressure only for the
production of /el/.
The length of time required to produce each diphthong
was not altered significantly by the application of pressure
The amount of time required to produce /a I/ and /el/ was
reduced significantly by anesthesia.
Vowel-Consonant-Vowel Production
/ i s i /
Anesthesia appeared to reduce the amount of vertical
and horizontal displacement for all sound elements of this
VCV. However, only the initial /i/ was reduced signifi
cantly, Table 18. The range of horizontal movement also


BIOGRAPHICAL SKETCH
The author was born in Chicago, Illinois on June 19,
1948. He moved with his family to Tampa, Florida, at the age
of four. In Tampa, he attended grammar school and high school.
In 1966, he enrolled at the University of South Florida (USF)
in Tampa and in 1970 he completed the requirements for a
Bachelor of Arts degree in Speech Science. Subsequently, he
was accepted into the Master's program at USF in Speech
Pathology and completed a six month internship at the Mailman
Center for Child Development in Miami, Florida. A Master of
Science degree was awarded in 1971. The author was accepted,
susequently, into the Doctoral progran in Speech Pathology
at the University of Florida, Gainesville, Florida. While
at the University of Florida, the author gained experience
as a research assistant, teaching assistant, and as a Speech
Pathology intern at the Veterans Administration Hospital in
Gainesville, Florida. In 1973, he was awarded a summer
internship to the University of Oregon Dental School by the
Joint Committee on Dentistry and Speech Pathology-Audiology.
The author is currently employed as a Research Speech Patholo
gist at the H.K. Cooper Institute for Oral-Facial Anomolies
and Communicative Disorders in Lancaster, Pennsylvania.
157


147
Table 32
Vowel-Consonant-Vowe 1 /aka/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
4.47
2.23
4.69
Verti cal
B
8.49
13.40
8.93
Jaw Psoi-
C
10.05
9.60
9.16
tion for
Mean
7.67
8.41
7.59
8.22
2
4.11
0.393
V1
S.D.
1 .66
3.28
1 .45
Two:
A
6.25
4.91
6.25
Horizontal
B
5.36
5.81
4.24
Jaw Posi-
C
5.14
4.91
6.03
tion for
Mean
5.58
5.21
5.51
1. 56
2
0.78
0.444
V1
S.D.
0.34
0.30
0.64
Three:
A
2.01
-0.45
2.23
Vertical
B
3.13
2.01
3.35
Jaw Posi-
C
8.04
7.59
7.59
tion for
Mean
4.39
3.05
4.39
24.00
2
12.00
2.571
C
S.D.
1 .85
2.38
1.63
Four:
A
5.36
3.57
5.81
Horizontal
B
5.81
5.58
4.91
Jaw Posi-
C
5.14
4.91
5.81
tion for
Mean
5.44
4.69
5.51
8.22
2
4.11
1.805
C
S.S.
0.20
0.59
0.30
Five:
A
6.25
2.01
2.46
Vertical
B
3.57
1.12
2.68
Jaw Posi-
C
10.72
8.26
7.82
tion for
Mean
6.85
3.80
4.32
106.90
2
53.44
13.942*
V2
S.D.
2.08
2.25
1 .75
Six:
A
6.48
5.14
6.03
Horizontal
B
5.81
5.58
5.14
Jaw Posi-
C
3.80
4.24
5.36
tion for
Mean
5.36
4.99
5.51
2.89
2
1 .44
1 .253
V2
S.D.
0.80
0.39
0.27


127
Table 24
Elevate Tongue Dorsum
Condition
Anes thes i a/
Summary:
Analysis
Repeated
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
One:
A
14.07
11.39
12.73
Vertical
B
2.01
-.67
1 .01
Jaw Posi-
C
4.02
5.70
4.36
tion at
D
11.39
8.71
11.39
TC
Mean
7.87
6.28
7.37
23.58
2
S.D.
2.89
2.59
2.81
Two:
A
9.72
9.38
11.01
Horizontal
B
5.70
4.02
4.36
Jaw Posi-
C
7.71
7.04
6.36
tion at
D
10.38
8.38
8.04
TC
Mean
8.38
7.20
7.45
13.58
2
S.D.
1 .06
1.16
1 .42
Three:
A
14.40
11 .06
12.40
Vertical
B
2.01
1.01
0.67
Jaw Posi-
C
4.36
6.70
4.02
tion at
D
12.06
13.60
15.08
TR
Mean
8.38
7.45
8.04
7.75
2
S.D.
3.05
2.71
3.40
Four:
A
10.05
9.72
10.05
Horizontal
B
5.36
3.02
4.02
Jaw Posi-
C
8.04
8.71
7.04
tion at
D
12.40
11.06
10.05
TR
Mean
8.97
8.12
7.79
13.00
2
S.D.
1 .49
1.77
1 .44
Five:
A
18.09
15.41
13.06
Vertical
B
2.68
2.01
1 34
Jaw Posi-
C
8.04
7.37
9.04
tion at
D
12.06
10.38
10.72
LT
Mean
10.22
8.79
8.54
29.09
2
S.D.
3.25
2.80
2.54
of
Measures
MS F
.79 2.809
.79 2.900
.88 0.725
.50 2.471
.54 2.678


155
Siirila, H. S. and Laine, P., Sensory thresholds in discrim
inating differences in thickness between the teeth, by
different degrees of mouth opening. PROG. FINN. DENT. SOC.,
68: 134-139 (1972).
Storey, A. T., Sensory functions of the temporomandibular
joint. J. CAAD. DENT. ASSN., 34: 294-30Q (1968),
Sussman, H. M. and Smith, K. U,, Transducer for measuring
mandibular movements, 0. ACOUST. SOC. AMER., 48; 857-858
( 1 970).
Sussman, H. M. and Smith, K. U,, Jaw movements under delayed
auditory feedback. J. ACOUST. SOC. AMER., 50: 685-691 (1971).
Sussman, H. M., MacNeilage, P. F., and Hanson, R. J., Labial
and mandibular dynamics during the production of bilabial
consonants: preliminary observations. J. SPEECH HEARING
RES., 16: 397-420 (1973).
Thilander, B., INNERVATION OF THE TEMPOROMANDIBULAR JOINT
CAPSULE IN MAN. Almquist and Niksells, Uppsala, Sweden:
Almquist and Niksells (1961).
Thompson, R. C., The effects of oral sensory disruption upon
oral stereognosis and articulation. A paper presented at
the annual convention of the American Speech and Hearing
Association, New York (1969).
Weinberg, B., Liss, G. M., and Hi 11 is, J. A., A comparative
study of visual, manual, and oral form identification in
speech impaired and normal speaking children. In J. F.
Bosma (Ed.) SECOND SYMPOSIUM ON ORAL SENSATION AND PERCEP
TION, Springfield, Illinois: Charles C Thomas (1970).
Weiss, C. E., The effects of disrupted 1ingual-palatal taction
on articulation. J. OF COMM. DIS. 2 : 14-1 9 ( 1 969a).
Weiss, C. E., The effects of disrupted 1ingual-palatal taction
on physiologic parameters of articulation. J. OF COMM. DIS.,
2: 312-321 (1969b).
Williams, W. N. and LaPointe, L.L., Relationships among oral
form recognition, interdental thickness discrimination, and
interdental weight discrimination. PERCEPT. MOTOR SKILLS,
35: 191-194 (1972).
Williams, W, N. and LaPointe, L.L., and Thornby, J. I., Inter
dental thickness discrimination by normal subjects. J, OF
DENT. RES,, (1974),
Wise, A., APPLIED PHONETICS, New York: Appleton-Century-
Crofts (1957).


124
Table 23
Elevate Tongue Tip
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
S u b ,i e c t
Normal
Anes thes i a
Pressure
SS
If
MS
F
One:
A
19.76
18.76
13.40
Vertical
B
3.35
3.02
2.34
Jaw Posi-
C
8.04
8.04
9.38
tion at
D
10.72
13.06
6.70
Tongue
Mean
10.47
10.72
7.96
83.25
2
41 .63
3.906*
Contact
S.D.
3.45
3.37
2.32
(TC)
Two:
A
7.70
9.72
9.72
Hori zontal
B
5.36
5.36
6 70
Jaw Posi-
C
4.69
4.36
4.36
tion at TC
D
7.37
7.04
5.70
Mean
6.28
6.62
6.11
2.33
2
1.17
0.779
S.D.
0.74
1.17
1.23
Three:
A
20.77
16.75
12.40
Vertical
B
3.02
1 34
0.34
Jaw Posi-
C
8.38
9.76
9.04
tion at
0
11.39
13.74
7.04
Tongue
Mean
10.89
10.38
7.20
142.30
2
71.17
7.078*
Release
S.D.
3.72
3.34
2.54
(TR)
Four:
A
7.37
8.71
9.04
Horizontal
B
5.36
4.69
4.02
Jaw Posi-
C
5.02
4.69
4.69
tion at TR
D
7.70
7.37
5.70
Mean
6.36
6.36
5.86
3.00
2
1 .50
0.877
S.D.
0.68
1 .00
1.11
Five:
A
21 78
20.10
13.06
Vertical
B
3.35
3.35
1 .01
Jaw Posi-
C
10.72
14.07
13.40
tion at
D
15.41
14.40
9.72
Lowest
Mean
12.81
12.98
9.29
154.33
2
77.17
5.491*
Tongue (LT)
S.D.
3.88
3.50
2.88


104
Table 21
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /aka/
Measures Condition Pairs
Vertical Displacement
Normal/
Anesthesia
Normal/
Anesthesia-
Pressure
Anesthesia/
Anesthesia-
Pressure
Initial Vowel /a/
Consonant /k/
Final Vowel /a-/
7.67/8.41
4.40/3.05
6.85/3.80*
7.67/7.59
4.40/4.39
6.85/4.32*
8.41/7.59
3.05/4.39
3.80/4.32
Horizontal Displacement
Initial Vowel la-1
Consonant /k/
Final Vowel /a./
5.58/5.21
5.43/4.68
5.34/4.98
5.58/5.51
5.43/5.51
5.34/5.51
5.21/5.51
4.68/5.51
4.98/5.51
Ranqe of Vertical Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
2.61/4.61*
3.50/5.51*
2.61/1.79
2.61/2.38*
3.50/3.20
2.61/0.82*
4.61/2.38
5.51/3.20*
1 .79/0.82
Ranqe of Horizontal Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
1 .27/1 .19
0.82/0.96
0.96/0.89
1.27/0.74
0.82/0.67
0.96/0.52
1.19/0.74
0.96/0.67
0.89/0.52
Duration of Production
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
9.89/10.22
3.67/4.33
6.22/5.89
9.89/9.89
3.67/3.67
6.22/6.22
10.22/9.89
4.33/3.67
5.89/6.22
p<. 05


58
above and illustrated in Figure 12. The following discussion
defines the vertical and horizontal measurements of mandibular
displacement.
Measurement of vertical mandibular position. Measurement
of the vertical position of the mandible was defined as the
perpendicular distance between the seperior tip of the mandi
bular central incisor and line AB. A positive value was
assigned when the tip of the lower central incisor was below
AB and a negative value was recorded when the tip of the
incisor was above line AB.
Measurement of horizontal mandibular position. The
horizontal position of the mandible was defined as the perpen
dicular distance between the tip of the mandibular incisor
and line CD. Positive values were assigned when the position
of the tip of incisor was posterior to the line CD. Negative
values were assigned when the tip of the incisor was observed
to be in front of line CD.
Identification of Frames Measured for the Speech and Nonspeech
Tasks
The initial and the final frames of each of the nonspeech
and the speech tasks were located and marked. The segment of
film portraying the production of each of the tasks was then
numbered consecutively, frame by frame, for ease of identifi
cation.
Nonspeech tasks
Tongue tip to alveolar ridge. The frame identified as the
initiation of this nonspeech task of elevating the tongue tip


142
Table 30 continued
Vowel-Consonant-Vowel /asa./
Summary:
Analysis of
Condi ti on Repeated Measures
Anes thesia/
Measure
Sub.iect
Normal
Anes thesia
Pressure
SS
df
MS
F
Seven:
A
0.
.89
1 .
79
0.
.67
Range of
B
5.
58
6.
70
6.
.03
Vertical
C
1 .
.34
2.
23
2.
01
Movement
Mean
2.
,60
3.
57
2.
.90
9.
,56
2
4.
,78
1 .
.085
from V-.
to V2
S.D.
1 .
.49
1 .
57
1 .
.61
Eight:
A
3.
,35
2.
90
3.
35
Range of
B
2.
.46
2.
46
0.
.89
Horizontal
C
3.
.80
4.
24
4.
,02
Movement
Mean
3.
20
3.
,20
2.
.75
2,
.67
2
1
.33
0.
.828
from Vi
S.D.
0.
.39
0.
. 54
0.
.95
to V2
Nine:
A
5.
.81
5.
.14
5.
.14
Range of
B
7,
. 59
9.
.60
9.
.60
Vertical
C
8.
,93
7.
,82
6.
.70
Movement
Mean
7.
.44
7.
,52
7.
,15
1
.56
2
0.
.77
0
.117
from Vi
to C
S.D.
0.
.90
1 .
.30
1 .
.31
Ten:
A
3.
.35
2.
.90
4.
.13
Range of
B
2.
.46
2.
.46
1 .
.12
Horizontal
C
3.
.57
3.
.80
3.
.80
Movement
Mean
3.
.13
3.
.05
2,
.68
2
.30
2
1
.15
1
.078
from Vi
to C
S.D.
0
.34
0.
.39
0.
.80
El even:
A
5,
.58
4,
.47
4.
.47
Range of
B
2
.01
2.
.90
3.
.57
Vertical
C
8
.04
5.
.81
4.
.91
Movement
Mean
5.
.21
4.
.39
4.
. 32
9
.85
2
4
.93
0
.636
from C
S.D.
1 .
.75
0.
.84
0
. 39
to V 2
Twelve:
A
3.
. 57
2.
.46
3,
.13
Range of
B
1
.34
1 .
.79
i.
.34
Horizontal
C
3
.35
3.
.35
2
.90
Movement
Mean
2
.75
2.
.53
2,
.46
0
.96
2
0
.48
0
.581
from C
S.D.
0
.71
0
.45
0.
.56
to V2


145
Table 31 continued
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condi ti on Repeated Measures
Anesthesia/
Measure Subject Normal Anesthesia Pressure £S df MS £
Seven:
A
0.89
0.67
0.45
Range of
B
1.34
1 34
1.12
Vert cal
C
0.22
0.67
0.45
Movement
Mean
0.82
0.89
0.67
0.52
2
0.26
0.336
from V,
to V2
S.D.
0.32
0.22
0.22
Eight:
A
0.22
0.67
0.22
Range of
B
0.22
0.22
0.67
Horizontal
C
0.89
0.67
0.67
Movement
Mean
0.44
0.52
0.52
0.22
2
0.11
0.143
from V-i
to V 2
S.D.
0.22
0.15
0.15
Ni ne :
A
0.89
1.12
0.67
Range of
B
1 .56
1 .34
1 .79
Vertical
C
0.45
0.45
0.22
Movement
Mean
0.97
0.97
0.89
0.07
2
0.04
0.043
from V
to C 1
S.D.
0.32
0.27
0.46
Ten:
A
0.22
0.22
0.00
Range of
B
0.67
0.67
0.89
Horizontal
C
0.22
0.45
0.45
Movement
Mean
0.37
0.47
0.47
0.07
2
0.04
0.084
from Vi
to C
S.D.
0.15
0.13
0.26
Eleven:
A
1.12
0.89
0.67
Range of
B
0.67
0.67
0.45
Vertical
C
1.34
1.79
0.67
Movement
Mean
1 .04
1.12
0.60
3.18
2
1.16
4.649*
from C
to Vj
S.D.
0.20
0.34
0.07
Twelve:
A
0.22
0.45
0.67
Range of
B
0.00
0.45
0.22
Horizontal
C
1.12
0.67
0.67
Movement
Mean
0.45
0.52
0.52
0.07
2
0.04
0.077
from C
S.D.
0.34
0.07
0.15
to V2


Figure 8
Acrylic Blocks for Assessing
Interdental Thickness Discrimination


Ill
studied. However, for the diphthongs /a I/ and /el/, anes
thesia significantly reduced the length of time used to pro
duce these sounds. This is interesting since anesthesia
appeared to increase the duration of the nonspeech oral
movements.
Vowel-Consonant-Vowel Production
Although significant differences resulted between values
for the normal and anesthesia conditions, ther did not appear
to be any consistent trend. There were no significant dif
ferences between the two conditions for the production of
/as cl/ or / i k i / The significant reduction of horizontal
displacement for the initial /i/ in /isi/ Table 18, and sig
nificant reduction in the vertical displacement of the final
/a/ in /a.ka/, Table 21, are difficult to explain except by
testing artifact. The significant increase in the measures
of the range of vertical movement for /o-ka./ most likely are
reflecting the affect of the significant reduction in vert
ical displacement for the final /a./.
Effect of Anesthesia: Summary
The data generated from this study suggests that there
appear to be some small disruptions in perception of jaw posi
tion, length of production, positioning of the mandible for
speech, and the range of motion throughout a speech task.
However, these data are not sufficient enough to support the
research findings of Thilander and her colleagues that sug
gested that the TMJ is active in the perception of jaw


2
caused by unilateral anesthetization of the TMJ capsule, can
be normalized by applying a painless pressure to the contra
lateral capsule (Larsson and Thilander, 1964). A review of the
literature has failed to reveal any further information rela
tive to the influence of anesthetization of the TMJ on the
control of mandibular position during speech function.
Therefore, the purpose of this study is basically
twofold: 1) to determine the effect of unilateral anestheti
zation of the TMJ on normal subjects' ability to position the
mandible during selected speech and nonspeech tasks and
2) to determine the effect of a painless pressure administered
to the TMJ contralateral to the one anesthetized on subjects'
ability to position the mandible during the same selected
speech and nonspeech tasks.
Anatomy and Physiology
The mandible, or lower jaw, is comprised of a horizontal
portion, the body, and two vertical portions, the rami. The
rami unite interiorly with the ends of the body. Superiorly,
the rami articulate with the temporal bone by way of the TMJ.
The complex movements of the mandible are made possible by
two groups of muscles, the muscles of mastication and the
suprahyoid muscles, and by the intricate function of the TMJ'S.
The purpose of this discussion is to describe the anatomy and
the physiology of the mandibular complex including the mandible,
the muscles that influence its movement and mandibular articu
lation with the skull. The following account relies primarily
on the description of Enlow (1971), Gray (1959), Mahan (1967),


CHAPTER FOUR
RESULTS
The results of this study will be presented relative to
1) descriptive analysis of the data and 2) statistical analysis
of differences between the experimental and control conditions.
Descriptive analysis was completed for the five perceptual mea
sures and the connected speech passage. Measurements of cen
tral tendency and the dispersion of performance on each of the
test measures accompanies a narrative description of the re
sults. Statistical analysis was completed for ten test mea
sures including the two nonspeech tasks, the four tasks of
diphthong production, and the four tasks of vowel-consonant-
vowel production. The statistical analysis included an ana
lysis of repeated measures and the Newman-Keuls analysis. A
more detailed description of the statistical procedures fol
lows the presentation of the results for the perceptual mea
sures and sentence production.
Analysis of Perceptual Tasks and Connected Speech
Perceptual Measures
Duplication of interdental space
This task was included in an attempt to replicate a
portion of Thilander's (1961) study. Table 1 displays subject
65


CHAPTER ONE
INTRODUCTION
The oral structures primarily responsible for normal
speech articulation include the lips, tongue, velum, teeth,
and mandible. Considerable information is available rela
tive to the normal placement and posture of these structures
for the production of normal speech elements. In addition,
several studies have demonstrated that there are identifiable
alterations in the speech signal following experimental
anesthetization of the oral structures (McCroskey, 1958;
McCroskey et a 1, 1 959 ; Ringel and Steer, 1 963; Schliesser
and Coleman, 1 968; Gammon et al 1971; and Scott and Ringel,
1971a) .
Further, a growing body of literature exists which deals
with the assessment of mandibular function. Specific varia
tions in mandibular placement have been observed for the pro
duction of certain speech sound elements (Kent and Moll, 1972
and Owens, 1973). The independent, yet complimentary, actions
of the tongue and the mandible and the lower lip and the man
dible have been recently described (Kent, 1972 and Sussman
et al., 1973). Other studies have demonstrated that subjects'
ability to perceive mandibular position for nonspeech tasks
is disrupted by anesthetization of the temporomandibular joint
(TMJ) capsule (Thilander, 1961). It has been reported also
that disruption in the perception of mandibular position,
1


39
it seems reasonable to suggest that disruption of the TMJ
sensory system would have a demonstrable effect on the overall
articulatory pattern of the mandible for speech production.
It might be suggested also then that the application of
pressure to the unanesthetized TMO might be expected to have
a normalizing effect on mandibular patterns of movement and
positions for speech. However, a review of literature has
failed to identify any investigation directly concerned with
the role of the TMJ sensory mechanism as related to the
regulation and control of mandibular movement and positioning
for speech sound production.
Statement of Purpose
Therefore, the purpose of this study is basically two
fold: 1) to determine what effects occur with unilateral
anesthetization of the TMJ relative to the positioning and
movement patterns of the mandible during selected perceptual
tasks, nonspeech oral movements, and a selected speech sample
and 2) to determine what effects occur with a subsequent
administration of a painless pressure to the TMJ capsule
opposite the one anesthetized on the positioning and movement
patterns of the mandible during selected perceptual tasks,
nonspeech oral movements, and a selected speech sample.
Specific Objectives
A series of tasks was devised in an attempt to measure
the effect of the anesthesia and pressure on the positioning


73
Table 5
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination for the Left
Condition
Subject
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
3.0 mm
1 .0 mm
1 .0 mm
2)
2.0
1 .5
1 .5
B
1)
LO
o
1.0
0.5
2)
1.5
1.0
ro
o
C
1)
1.0
1 .5
0.5
2)
1.0
1 .0
0.5
D
1)
2.0
2.5
1.5
2)
2.5
3.5
2.5
Means
1.69 mm
1.62 mm
1.25 mm
Standard
Deviation
0.84
0.92
0.76


77
condition means.
Table 8 presents the mean percent of correct subject
responses per stimulus pair for the task of lateral jaw posi
tion discrimination to the right of midline. These data
demonstrate also that subjects' ability to perceive differ
ences in positions to the right of midline was hampered by
the application of pressure to the left TMJ capsule.
Anterior-posterior jaw position discrimination
Table 9 presents the individual and group performance
scores for anterior-posterior jaw position discrimination.
The group means illustrate that the subjects'; performance
was equal for the anesthesia and the pressure conditions.
Table 10 presents the mean percent of correct subject re
sponses per stimulus pair for this task. Subjects per
formed less accurately in discrimination between pairs of
anterior-posterior jaw positions under the normal control
condition than under the experimental conditions. 100%
performance was attained when the difference between pairs
was 1.0 mm for the anesthesia and the pressure conditions.
For the normal condition, 100% performance was not reached
until the difference between pairs of jaw positions was
2.5 mm.
Discrimination of interdental weights
Individual and group performance scores for the task
of interdental weight discrimination can be found in Table
11. The anesthesia condition had little effect on subjects'


32
too surprising since the swallow patterns include dental
occlusion and thus provided added feedback from the perio
dontal ligament. In addition, there is no reason to suspect
that the temporomandibular articular receptors provide any
feedback which would influence the oral structures involved
in swallowing as they appear to be more active in conscious
positioning of the mandible and the mandible is already po
sitioned at the iniation of the swallow sequence.
Several other researchers have explored the nature of
the control of the mandible for dynamic masticatory function
either directly or indirectly. Shepherd (1960) reported that
the total movement of the mandible decreased with age, use
of dentures, and introvert personality type. Denture wearers
demonstrated similar masticatory patterns with and without
their dentures, however, as might be expected, the amount of
vertical movement was much greater without dentures. The
masticatory pattern was also unchanged prior to and after
complete teeth extraction. However, abnormal masticatory
patterns were evident in individuals who demonstrated exces
sive occlusal wear and who had pain, clicking, or other symp
toms of TMJ dysfunction. The author reported that in no case
where the TMJ was showing abnormal symptoms was the associated
masticatory cycle considered to be normal. In many cases,
marked irregularities occured in the patterns with a lack of
smoothness in individual cycles and sometimes there was a
complete lack of rythm from cycle to cycle.
These findings were supported by Atkinson and Shepherd
(1961). In one patient whose TMJ dysfunction was diagnosed


UNIVERSITY OF FLORIDA
3 1262 08554 7163


66
Table 1
Individual Performance Scores and Group Means,
Ranges
Space
Subject
, and S.D.'s for Duplication
Task: Range of Jaw Position
Condition
of Interdental
for Ten Trials
Norma 1
Anesthetized Anesthetized and Pressure
A
3.0 mm
5.0 mm
3.0 mm
B
8.0
4.0
2.0
C
2.0
6.0
7.0
D
11.0
7.0
4.0
Means
6.00 mm
5.50 mm
4.00 mm
Standa rd
Deviation
4.24
1.29
2.16


146
Table 31 continued
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure SS
df
MS
F
Thirteen:
A
8.71
7.82
8.04
Time from
B
7.15
6.92
6.25
V, to V,
C
7.82
7.37
6.92
Mean
7.89
7.37
7.07 6.89
2
3.44
3.221
S.D.
0.45
0.26
0.52
Fourteen:
A
2.90
1.56
2.23
Time from
B
2.68
2.46
2.90
V1 to C
C
2.01
1 .79
2.01
Mean
2.53
1 .94
2.38 3.85
2
1 .93
2.144
S.D.
0.27
0.27
0.27
Fifteen:
A
5.81
6.25
5.81
Time from
B
4.47
4.47
3.35
C to V2
C
5.81
5.58
4.91
Mean
5 36
5.43
4.69 6.74
2
3.37
3.165
S.D.
0.45
0.52
0.72


63
closing off the velopharyngeal port.
6. The /a/ of "Connie" was defined as the lowest and most
posterior point of lingual movement preceding the lingual-
alveolar contact required for the production of the phoneme
/n/ of Connie" .
7. The /n/ of "Con_nie" was defined as the 1 i ngual-al veol ar
contact required for its production.
8. The /w/ of "watches" was defined by the maximum forward
movement of the lips required for its production,
9. The A>V of "watches" was defined as the lowest and most
posterior point of lingual movement preceding the lingual
alveolar contact required for the production of the / tf /
of the word "watches".
10. The / ff / of "watches" was defined as the 1 i ngual-al veol ar
(sometimes 1ingual-pa 1 a tal ) contact required for its pro
duction while the teeth were closed and the lips pro
truded slightly.
11. The /t/ of "TV" was defined as the lingual-alveolar con
tact required for its production.
12. The first /i/ of "Tee Vee" was defined as the highest point
of ligual movement preceding the 1abial-dental contact re
quired for the production of the phoneme /v/ of "TV_".
13. The /v/ of "TV/1 was defined as the labial-dental contact
requiredforitsproduction.
14. The second /i/ of "Tee Vee/' was defined as the highest
point of lingual elevation preceding the forward move
ment of the lips required for the production of the
phoneme /w/ of "with".


144
Table 31
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure
SS
df
MS
F
One:
A
1 .56
2.01
2.90
Vertical
B
3.35
3.57
2.46
Jaw Posi-
C
5.58
5.36
4.91
tion for
Mean
3.50
3.65
3.42
0.52
2
0.26
0.173
h
S.D.
1.16
0.97
0.75
Two:
A
5.36
4.91
5.58
Horizontal
B
3.35
2.46
2.90
Jaw Posi-
C
5.36
4.91
4.69
tion for
Mean
4.69
4.09
4.39
3.56
2
1 .78
1 .730
V1
S.D.
0.67
0.82
0.79
Three:
A
1.12
1.12
2.46
Vertical
B
1 .79
2.68
0.67
Jaw Posi-
C
5.14
5.36
4.69
tion for
Mean
2.68
3.05
2.61
2.30
2
1.15
0.679
C
S.D.
1 .24
1 .24
1.16
Four:
A
5.14
4.69
5.58
Horizontal
B
3.35
2.68
2.46
Jaw Posi-
C
5.58
5.36
5.14
tion for
Mean
4.69
4.24
4.39
2.07
2
1 .04
1 .931
C
S.D.
0.68
0.80
0.97
Five:
A
0.67
1 34
2.46
Vertical
B
2.01
2.23
1 .34
Jaw Posi-
C
5.81
6.03
4.91
tion for
Mean
2.83
3.20
2.90
1 .56
2
0.78
0.629
V2
S.D.
1.54
1 .44
1 .05
Six:
A
5.14
4.69
6.03
Horizontal
B
3.35
2.90
2.68
Jaw Posi-
C
4.69
4.69
4.47
tion for
Mean
4.39
4.09
4.39
1 .18
2
0.59
0.934
S.D.
0.54
0.60
0.97


LIST OF TABLES CONTINUED
Table Page
28 Diphthong /D\/ 136
29 Vowel-Consonant-Vowel /i si / 138
30 Vowel-Consonant-Vowel /asa-/ 141
31 Vowel-Consonant-Vowel /i ki/ 144
32 Vowel-Consonant-Vowel /oXa-/ 147
vi i


90
anesthesia (p<.05).
Elevation of tongue dorsum
The measurements and calculations made for this task
requiring each subject to elevate the dorsum of the tongue
three times were similar to those for the preceding task of
tongue tip elevation, Table 13. No statistically significant
differences existed between conditions for the measures of
tongue dorsum elevation. However, there was a trend for the
length of production to increase with anesthesia and increase
even more with the application of pressure.
Summary: nonspeech oral movements
When comparing the two tasks of tongue elevation, it
was observed that the jaw was vertically displaced more for
tongue tip elevation than for tongue dorsum elevation. This
was unexpected since speech tasks involving similar speech
movements would result in less vertical displacement of the
mandible for 1ingual-alveolar sound production than for
production of 1 ingua1 -velar sounds.
More expected was the greater horizontal displacement
of the mandible for tongue dorsum elevation. The range of
horizontal movement was also greater for this task suggesting
that in order to achieve 1ingual-velar contact, the tongue
and jaw act in unison to retrude and elevate the tongue.
The time required to complete a trial appears to be equivalent
for both of the nonspeech tasks. In addition, 1ingual-alveo-
lar and 1ingual-velar contact appeared to be maintained
equally as long for each task.


35
and the tongue. It is now obvious that the tongue does not
move in complete harmony with the mandible (Kent, 1972).
Kent (1972), who studied the relationship of tongue body and
mandibular movement during speech, concluded that the overall
displacements of the tongue body and jaw vary with phonetic
context. He also identified a "trading relationship" between
the tongue and the mandible; the smaller the amount of jaw
movement, the greater must be the extent of tongue motion.
Sussman et al. (1973) reported that although the jaw
and the lower lip are mechanically linked and constrained by
each other, they also act as independent articulators, each
reflecting their own specific movement characteristics. He
also reported that the less the jaw contributes to the forma
tion of a bilabial stop, the higher the elevation of the lower
lip.
This independence in movement between jaw and tongue
and jaw and lip might be interpreted as evidence for separate,
yet interconnecting feedback systems where one system is
responsible for monitoring the other and compensating for it.
Further research of mandibular and tongue body dynamics
reveals similarities in the relationship of movement velocity
to displacement. That is, the greater the displacement of the
structure during speech, the greater the velocity of movement
(Abbs et al , 1 972; Sussman et al 1 973; and Kent and Moll,
1 972).
There is research in the literature that assists in
understanding the complex interplay between the mandible and


CHAPTER TWO
STATEMENT OF PROBLEM
The literature reviewed in CHAPTER ONE suggests that
experimental anesthetization of the oral structures results
in quantifiable alterations in subjects' performance on
oral-sensory-perceptual tasks as well as alteration of cer
tain characteristics of speech production. The literature
reviewed has revealed also that mandibular position is spe
cific for certain phonetic productions. In addition, these
studies reveal that the sensory mechanism within the TMJ
apparently controls, to some degree, the movement and posi
tioning of the mandible. Moreover, it would appear that
measurement strategies, such as duplicating an interdental
space (Thilander, 1961) or interdental thickness discrimin
ation (Williams and LaPointe, 1972 and Williams et al. ,
1974) might be used in determining as index of sensory in
tegrity of the TMJ. The literature reviewed has demonstrated
further that the effect of anesthetizing one TMJ can be nor
malized by a painless pressure applied to the contralateral
capsule (Larsson and Thilander, 1964).
If anesthetization of the TMJ causes impairment in the
regulation and control of mandibular position, and if fine
sensory motor coordination of jaw placement and movement is,
in fact, critical for the production of normal speech sounds,
38


81
ability to discriminate between paired weights. Group means
are 7.62 gms for the normal condition and 7.12 gins for the
anesthesia condition. Pressure appeared to make discrimina
tion between interdental weights more difficult. The mean
difference required was 8.62 gms for this condition.
Summary: perceptual measures
Anesthesia to the right auriculotemporal nerve appeared
to have a mild disruptive influence on this group of subjects'
abilities to discriminate between the thickness of pairs of
blocks placed interdentally. Pressure to the contralateral
(left) TMJ capsule restored discriminative ability somewhat
(Tables 3 and 4) .
Pressure to the left TMJ appeared to enhance subject
performance of tasks where anesthesia had no disruptive
effects. These tasks include Thilander's task of replicating
a standard interdental space ten times (Table 1), discrimi
nation between pairs of lateral jaw positions to the left of
midline (Table 5), and discrimination between pairs of
anterior-posterior jaw positions (Table 9). On the other
hand, pressure to the left TMJ capsule appeared to be dis
ruptive of subjects' ability to discriminate between pairs
of lateral jaw positions to the right of midline (Tables 7
and 8). Pressure appeared to have a disruptive effect on
subjects' ability to discriminate between the weights of
capsule pairs placed between the incisors (Table 11). Neither
of the experimental conditions appeared to influence the
subjects' performance on Thilander's task of duplicating a
standard jaw position when that task ia analyzed by the mean


Figure 9
Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination


116
Diphthong Production
Vertical jaw displacement was also significantly
reduced for the initial position for / a I /, /el/, and /al)/
(Tables 14, 15, and 16). Additionally, the range of verti
cal movement was significantly reduced for /a I/ and /aU/.
Again, these data suggest that pressure to the TMJ re
stricts jaw displacement and presents evidence that pres
sure also reduces the range of vertical movement.
Vowel-Consonant-Vowel Production
The data generated for the measures of mandibular
positioning, range of motion, and length of production for
the vowel-consonant-vowels suggest that the application of
pressure did not restrict jaw opening as severely as was
observed for the diphthong tasks. These data agree with
those obtained for diphthong production, in that maximum
jaw displacement for the low vowel /a./ did not exceed
8.5 mm. It was observed previously, for the diphthong
tasks, that jaw opening was not significantly reduced until
jaw displacement exceeded 10 mm.
It is interesting to note that pressure reduced the
time required to produce /isi/ (p<.05) and /iki, but not
/-Sa./ and /aka/. This supports previous observations that
the TMJ offers some feedback in the temporal domain. It
suggests further that feedback is supplied differentially
between closed movements, such as for /isi and /iki/ and
for open jaw positions, such as for /a.so./ and /aka/.
Also observed for the production of these sound


11
Internal Pterygoid (Medial). The origin of this muscle
is along the lateral pterygoid plate and the perpendicular
plate of the palatine bone. Insertion into the mandible is
along the posterior medial surface of the ramus and the
angle of the mandible, and innervation is from the mandibu
lar branch of the Trigeminal nerve. It serves to protrude
and to elevate the mandible and also assists in the rotary
movement for chewing.
Suprahyoid Muscles
My 1ohyoid This muscle originates along the mylohyoid
line of the mandible and inserts along the median raphe from
the chin to the hyoid bone. It is innervated by the mylo
hyoid branch of the Trigeminal. It elevates the hyoid bone
and the base of the tongue, but also assists in depressing
the mandible.
Geniohyoid The mental spine of the mandible is the
origin of this muscle. It inserts on the body of the hyoid
bone and is innervated by the first and second cervical
nerves through the Hypoglossal nerve. It functions to ele
vate the hyoid bone and move it anteriorly as well as to de
press the mandible.
Digastricus (anterior belly). The anterior belly of
the Digastricus originates from the inner surface of the
mandible near the symphysis. It inserts into the inter
mediate tendon of the hyoid bone. It is innervated by the
mylohyoid branch of the Trigeminal nerve. It also serves
to elevate the hyoid bone and to depress the mandible.


115
of subjects' ability to discriminate lateral positions to the
right of midline, Table 7, This might have been expected
since jaw movement to the right requires lateral condylar mo
tion on the left side. These data suggest that pressure in
terfered with subjects' discriminative abilities either me
chanically or by reduction of sensory feedback.
Sentence
The effect of pressure on vertical and horizontal jaw
positioning for a connected speech passage are presented in
Figures 13 andl4 respectively. Although pressure had no
discernable effect of the horizontal positioning of the jaw,
this experimental procedure consistently reduced the amount
of vertical displacement throughout the speech sample. This
consistency suggests that pressure mechanically restricted
or reduced jaw movement during connected speech.
Nonspeech Tasks
The data for these tasks were presented in Tables 12
and 13. Table 12 illustrates that pressure significantly
reduced the amount of vertical displacement throughout the
task of tongue tip elevation. Again, the reduction in dis
placement is believed to be the result of a restriction of
the translational movement of the condyle. It is interesting
to note that pressure did not have the same reducing affect
for tongue dorsum elevation. It appears that pressure re
stricts movement past a certain vertical opening and that
opening was not reached for dorsum elevation.


82
difference of jaw positions from the standard postion.
Sentence
Figure 13 combines a tabular and graphic representation
of the vertical jaw displacement (N = 4) for the seventeen
phonemes under each of the three conditions. The mean, range,
and standard deviation are entered below each phoneme. Figure
14 presents the complimentary data for horizontal mandibular
displacement. Since measures from the film were made at one
and one-half life size (Chapter Two), all measurement values
were reduced by one-third to achieve absolute values. Statis
tical significance could not be assessed due to the small
number of observations.
Figure 13 demonstrates that similar vertical patterns of
jaw movement are maintained under each of the test conditions.
The most closed jaw postures are observed for the /tj / in
"watches" and the /t/ in "XV." The greatest amount of mandi
bular displacement is observed for the /a/ in "Cojnnie" and the
/a./ in "watches." These observations are compatible with
previous research findings (Kent and Moll, 1972 and Owens,
1 973).
In general, vertical jaw displacement was greatest for
the anesthesia condition and least for the pressure condition.
Under anesthesia, jaw displacement was equal to normal for the
initial speech sounds in the sentence. As the amount of re
quired displacement increased for the open sounds in "Connie"
and "watches," the jaw opened more for the anesthesia condi
tion than for the normal condition. As the


60
Vowel-consonant-vowel s : /isi/, /asa./, / i k i / and /aka,/
Those frames identified as the beginning and the end of
each VCV sequence were defined in terms of optimal lingual
placement for the production of the two vowels /i/ and /a/.
The frame showing the vowel /i/ as it occurred in the
initial position of the VCV sequence was defined as that frame
picturing the tongue in its highest position prior to its
movement for the production of the following consonant. The
frame showing the vowel /a./ as it occurred in the initial
position was defined as that frame showing the lowest tongue
position prior to its movement for the production of the
following consonant.
The frame showing the vowel /i/ as it occurred in the
final position of the VCV sequence, was defined as that frame
showing the tongue in its highest position prior to its move
ment to a rest position. The frame showing the vowel /a/, as
it occurred in the final position of the VCV sequence, was
defined as that frame showing the tongue in its lowest position
prior to its movement to a rest position.
In addition to the initial and the final frames of each
trial, those frames depicting the lingual palatal contact
required for consonant production were identified. Thus, it
was possible to define the vertical and the horizontal position
of the mandible at start and finish of each trial as well as
during consonant production. These measurements also provided
the range of mandibular motion throughout each trial. The
length of time for the completion of each trial and the amount
of time required for the production of the consonants and the
vowels were recorded also.


75
Table 7
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Ri ght
Condition
Subj ect
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
1 ,
. 5 mm
2.
. 5 mm
2.
. 5 mm
2)
1 .
.0
1 .
.0
1 .
.0
B
1)
2.
.0
1 .
,0
2.
.0
2)
1 .
.0
1 .
.5
2.
.0
C
1)
1 .
.0
0.
,5
1 .
.0
2)
0.
. 5
0.
.5
0.
.5
D
1)
0.
.5
1 .
,5
4.
.5
2)
1 ,
.5
3.
.0
3.
.0
Means
1.12 mm
1.45 mm
2.06 mm
Standard
Deviation
0.52
0.23
0.74


20
function will be discussed in reference to the physiological
processes of mastication, deglutition, and speech.
Sensory Interruption
Fairbanks (1954) proposed a feedback loop theory of
speech production in which he hypothesized that tactile and
kinesthetic feedback, in addition to auditory feedback, are
necessary for normal speech production. The importance of
auditory feedback for speech production is supported by the
results of investigations which have demonstrated that de
laying the air borne auditory signal (delayed auditory feed
back) of normal speakers typically results in an aberrant
speech pattern characterized by dysfluency, general articu
lation inaccuracy and modification of speech sound duration,
the fundamental frequency and the sound pressure level (Lee,
1950; Black, 1951; and Fairbanks, 1955). The need for tactile-
kinesthetic information has been supported by researchers who
have demonstrated that there is a relationship between oral-
sensory integrity and articulation proficiency (McCroskey,
1958; McCroskey et al., 1959; Ringel and Steer, 1963: Schliesser
and Coleman, 1968; Thompson, 1969; Gammon et al., 1971; Scott
and Ringel, 1971a; Scott and Ringel, 1971b; Horii et al, 1972;
and Borden, 1 97 3).
The task of oral stereognosis, which involves the iden
tification of plastic shapes presented intra-orally has evolved
recently as a possible indicator of oral sensory integrity.
Research has indicated that the subjects' performance


76
Table 8
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Mandibular Position Discrimination to
the Right
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm
-
0.5
mm
37.5%
25%
25%
0
mm
-
1 .0
mm
75
50
50
0
mm
-
1.5
mm
87.5
87.5
50
0
mm
-
2.0
mm
100
87.5
75
0
mm
-
2.5
mm
100
87.5
75
0
mm
-
3.0
mm
100
100
87.5
0
mm
-
3.5
mm
100
100
100
0
mm
-
4.0
mm
100
100
87.5
0
mm
-
4.5
mm
100
100
100
0
mm
5.0
mm
100
100
100


24
neuromuscular control of mandibular movement and positioning
for these processes. The following literature review presents
the current understanding of mandibular kinesthesia and man
dibular and TMJ function for the processes of deglutition,
mastication, and speech.
Mandibular kinesthesia
Oral kinesthesia has been defined by Ringel et al.
(1967) as the sense by which muscular motion, weight, and po
sition of an oral structure is perceived. Rose and Mountcas-
tle (1959) previously established that intact joint receptors
and central nervous system relay networks are required for
kinesthesia. Mountcastle and Powell (1959) confirmed that
specific joint endings with cortical projections respond to
absolute degrees of arc or joint angles. Thus, defining
mandibular kinesthesia as the sense of perceiving the posi
tion, motion, and weight of the mandibular structure appears
completely acceptable. Research indicates, however, that
Subjects' performance on tasks of interdental thickness dis
crimination (mandibular position) is unrelated to their per
formance on tasks of interdental weight discrimination and
that different receptors may be responsible for the percep
tion of mandibular position and the interdental perception
of weight (Williams and LaPointe, 1972).
The study of mandibular kinesthesia in normal human
individuals has concentrated primarily on subjects' ability
to discriminate differences in mandibular positions. Although
instrumentation has varied, the results reported by various


112
posture. The findings of the present study are in agreement
with Siirila and Laine (1972) who found no disruption in sub
ject abilities on a test of interdental thickness discrimina
tion under bilateral anesthetization of the TMJ's,
The consistent disruption of abilities reported by
Thilander and her colleagues have not been replicated in two
seperate studies Several explanations may account for the
differences in the results of these studies. Thilander util
ized an intracapsular injection procedure, whereas, the auri
culotemporal nerve was anesthetized in the present study. It
might be suspected that intracapsular injection results in
a more complete anesthetization of the TMJ sensory endings.
Thilander (1961) demonstrated that the TMJ capsule was
innervated by a major branch of the auriculotemporal nerve
and small slips from the masseteric and the deep temporal
nerves. It is the posterior and lateral aspects of the cap
sule that are the most richly innervated; these by the auri
culotemporal nerve. The anterior aspect of the capsule is
sparsely innervated by small twigs from the auriculotemporal,
posterior deep temporal, and masseteric nerves. The medial
aspect is served also by twigs from the auriculotemporal and
masseteric.
It may be hypothesized that feedback provided by the
masseteric and deep temporal nerves supply sufficient infor
mation to retain joint position sense even following the
blocking of the auriculotemporal nerve. Although, less fre
quently represented, the masseteric has a greater percentage


no
suggests that jaw positioning makes use of the tactile
feedback provided by the lingual-alveolar and lingual-palatal
contact provided in the production of the sound elements /tj/
and /t/. This is interesting since the anterior portion of
the tongue, used in the production of these two sounds, is
more richly innervated with sensory endings than the pos
terior. It further suggests that more than one sensory
system may provide information of jaw posturing.
Nonspeech Tasks
Anesthesia appeared not to influence any of the mea
sures of displacement or range of motion for the two tasks of
nonspeech oral movement. However, anesthesia did appear to
increase the length of time required to complete these tasks.
The increase was significant for tongue tip elevation from
the point when the tongue contacted the alveolar ridge to
the time when the tongue released that contact. Since this
is a period of limited jaw movement, as evidenced by the
limited range of movement during that time, it might be sus
pected that the sensory receptors of the TMJ process in
formation in the temporal domain. It may be proposed also
that the processing of this information is disrupted by
unilateral anesthetization of the auriculotemporal nerve.
Diphthong Production
The anesthetization procedure utilized in this study
appeared to have no influence on the displacement or the
range of motion of the mandible for the four diphthongs


88
Table 12
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Tongue Tip Elevation
Measures Condition Pairs
Vertical Displacement
Tongue Contact
Tongue Release
Lowest Tongue
Normal/
Anesthes i a
10.45/10.72
10.92/10.38
12.80/13.00
Normal/
Anesthesia-
Pressure
10.45/7.97*
10.92/7.24*
12.80/9.31*
Anesthesia/
Anesthesia-
Pressure
10.72/7.97
10.38/7.24*
13.00/9.31*
Horizontal Displacement
Tongue Contact
Tongue Release
Lowest Tongue
6.28/6.62
6.36/6.36
6.77/6.97
6.28/6.12
6.36/5.86
6.77/6.28
6.62/6.12
6.36/5.86
6.97/6.28
Ranqe of Vertical
Movement
Tongue Contact
Tongue
Tongue Contact
Release
Tongue Release
Tongue
to Lowest
to Tongue
to Lowest
2.51/2.26
1.17/1.51
2.43/2.68
2.51/2.34
1.17/1.43
2.43/2.60
2.26/2.34
1.51/1.43
2.68/2.60
Ranqe of Horizontal Movement
Tongue Contact
Tongue
Tongue Contact
Release
Tongue Release
Tongue
to Lowest
to Tongue
to Lowest
0.34/0.67
0.59/0.76
0.67/1.09
0.34/0.84
0.59/0.84
0.67/0.92
0.67/0.84
0.76/0.84
1.09/0.92
Duration of Production
Tongue Contact to Lowest
Tongue 20.50/25.50 20.50/24.63 25.50/24.63
Tongue Contact to Tongue
Release 10.00/14.63*10.00/12.75 14.63/12.75
Tongue Release to Lowest
Tongue 10.50/10.88 10.50/11.88 10.88/11.88
p<. 05


132
Table 26
Diphthong /el/
Summa ry:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
14.29
14.52
10.72
Vertical
B
6.25
4.91
5.81
Jaw Posi-
C
8.26
10.72
8.26
tion for
D
14.07
12.28
10.50
Initial
Mean
10.72
10.61
8.81
60.66
2
30.33
5.945*
Frame
S.D.
2.04
2.05
1.15
Two:
A
4.47
5.58
5.36
Horizontal
B
7.37
5.81
6.92
Jaw Posi-
C
4.24
3.80
2.90
tion for
D
7.15
5.81
6.03
Initial
Mean
5.81
5.25
5.30
5.06
2
2.53
1 .790
Frame
Three:
A
10.94
11.39
7.15
Vertical
B
2.46
1.12
2.68
Jaw Posi-
C
1.79
2.01
2.90
tion for
D
5.36
6.03
4.47
Initial
Mean
5.14
5.14
4.12
12.50
2
6.25
1 .467
Frame
S.D.
2.03
2.34
1.03
Four:
A
2.90
4.47
4.47
Horizonta 1
B
4.24
3.80
5.36
Jaw Posi-
C
3.80
2.90
2.01
tion for
D
4.02
3.80
3.57
Final
Mean
3.74
3.74
3.85
0.22
2
0.11
0.061
Frame
S.D.
0.29
0.32
0.71
Five:
A
3.35
3.13
3.80
Range of
B
3.80
3.80
3.13
Vertical
C
6.92
8.93
5.36
Movement
D
8.71
6.25
6.03
Mean
5.70
5.53
4.58
19.39
2
9.69
1 .903
S.D.
0.80
1 .32
0.67


22
view of a closed-loop feedback system was reported by
MacNeilage (1970) and Abbs and Netsell (1973).
Hixon and Hardy (1964), on the other hand, proposed
that speech movements were programmed. This view was
supported by Kent (1973) who found time intervals between
articulatory events were too short to accommodate the use of
feedback. Kent (1973) proposed that speech is more likely
operating under open-loop control or that speech is pre
programmed centrally. He postulated that feedback might be
employed in a reset capacity to allow for occasional
adjustment of the motor program.
Although much of the discussion regarding feedback
control is theoretical, interpretation of current evidence
suggests that both closed-loop and open loop control systems
are actively involved in motor control of speech (Putnam
and Ringel, 1972 and Abbs, 1973). Thus, after a speech
sequence is triggered initially as a unit, peripheral sensory
mechanisms make fine adjustments. Such a theory may help
explain why only minor distortions of the speech signal are
observed when bilateral mandibular blocks are performed.
Mandibular Position Movement
The limited amount of research on mandibular positioning
can be attributed to the absence of convenient and accurate
transduction techniques. Geissler (1971) outlined three
requirements for instrumentation. It should be able to record
a large number of patients, should not interfere with normal
mandibular movements, and should allow continuous recording
during mandibular movement.


64
15. The IQI of "with" was defined as the 1ingual-dental
contact required for its production.
16. The /m/ of "me" was defined as the bilabial contact re
quired for its production.
17. The /i/ of "me_" was defined as the highest point of
lingual elevation following the bilabial contact required
for the production of the phoneme /m/ of "me".
Re iabi1ity
Since the author made all measurements, only inter
measurer reliability was assessed. The vertical and horizontal
measurements were remeasured for forty-five frames. The cor
relation between the initial and the second measurements was
calculated. A correlation coefficient of .99 was obtained for
the forty-five vertical measurements and a coefficient of .97
was obtained for the forty-five horizontal measurements. These
correlation coefficients are considered to be within acceptable
limits.


92
Diphthong Production
Diphthong: /a I/
The amount of vertical and horizontal displacement was
measured at the initiation and the completion of diphthong
production. Analysis of the two vertical measures revealed
that anesthesia did not alter the initial, starting position
of the jaw, Table 14. The starting position was reduced
significantly by the application of pressure (p .05). The
final, or ending, vertical position was not altered signifi
cantly by either of the experimental conditions. However,
the range of vertical movement from the starting to the ending
position was reduced significantly by the application of
pressure. The amount of time required to produce /a I/ was
reduced significantly by anesthesia. Neither the initial and
final horizontal displacement nor the range of horizontal
movement varied significantly under the experimental condi-
tions.
Diphthong: /el/
The paired values for the three conditions of /el/
production are presented in Table 15. Again, while anesthesia
did not alter the starting position of the jaw, the application
of a light pressure significantly reduced this position. The
range of vertical movement did not vary significantly between
any of the condition pairs. However, the range of horizontal
movement was reduced significantly by the application of
pressure when compared to the normal condition, but not when
compared to the anesthesia condition.


I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality
as a dissertation for the degree giBs-cJmr of Philosophy.
Parker E. Mahan
Professor of Dentistry
This dissertation was submitted to the Graduate Faculty
of the Department of Speech in the College of Arts and
Sciences and to the Graduate Council, and was accepted as
partial fulfillment of the requirements for the degree of
Doctor of Philosophy.
August, 1976
Dean, Graduate School


153
Manly, R. S., Pfaffman, C., Lathrop, D. D., and Keyser, J.,
Oral sensory thresholds of persons with natural and arti
ficial dentitions. J. DENT. RES., 31 : 305-31 2 Cl 952 ) .
Marshall, R. C. and Jones, R. N,, Effects of a palatal lift
prosthesis upon the intelligibility of a dysarthic patient.
J. PROSTH. DENT., 25: 327-332 (1971).
McCroskey, R. L., The relative contribution of auditory
and tactile cues to certain aspects of speech. SOUTHERN
SPEECH JOURNAL, 24: 84-90 (1958).
McCroskey, R. C., Corley, N. W., and Jackson, G., Some effects
of disrupted tactile cues upon the production of consonants.
SOUTHERN SPEECH JOURNAL, 25: 55-60 (1959).
McNutt, J. C., Oral sensation and motor abilities of /s/ de
fective /r/ defective and normal speaking junior high
school students. A paper presented at the annual convention
of the American Speech and Hearing Association, Detroit,
Michigan (1973).
Moser, H., LaGourgue, J. R,, and Class, L., Studies of oral
stereognosis in normal, blind, and deaf subjects. In J. F.
Bosma (Ed.) SYMPOSIUM ON ORAL SENSATION AND PERCEPTION,
Springfield, Illinois: Charles C Thomas (1967).
Mountcastle, V. B. and Powell, P., Central nervous mechanisms
subserving position sense and kinesthesis. BULLETIN: JOHN
HOPKINS HOSPITAL, 105: 173-200 (1959).
Moyers, R. C., HANDBOOK OF ORTHODONTICS, Chicago: Yearbook
Medical Publishers (1973).
Owens, D. E., A cinefluorographic study of horizontal and
vertical mandibular movement patterns for normal speakers.
Master's Thesis, University of Florida (1973).
Perry, C., Neuromuscular control of mandibular movements.
J. PROSTH. DENT., 30: 714-720 (1973).
Posselt, U. and Thilander, B., Influence of the innervation
of the temporomandibular joint capsule on mandibular bor
der movements. OCTA ODONT. SCAND., 23: 601-613 (1965).
Putnam, A. H. B. and Ringel, R. L,, Some observations of
articulation during labial sensory deprivation, J, SPEECH
HEARING RES., 15: 529-542 (1972),
Ransjo, K. and Thilander, B,, Perception of mandibular posi
tion in cases of temporomandibular joint disorders.
0D0NT0L. FOREN. TIDSKR,, 11: 134-144 (1963).


54
amount of pressure used was 1.8 pounds.
The pressure device was attached to a cephalostat,
which is also illustrated in Figure 11. The cephalostat
was designed to fit around the subject's head, in a halo
fashion, with four points of contact for stabilization, two
anteriorly and two posteriorly. This desiqn prevented any
interference with the movement of the muscles of mastica
tion. Both the cephalostat and the pressure device were
desiqned by the author and were constructed in the Bioinstru
ment Shop at Shands Teaching Hospital, University of Florida.
Filming Procedures
The nonspeech oral movements and speech tasks were re
corded cinef1uoroscopically. A 16 mm Auricon Cine II Voice
camera mounted on a Picker fluoroscope, with a five inch
image intensifier, was used to obtain the cinefluorographic
films of the speech structures during the production of the
nonspeech oral movements and during production of the speech
sample. Eastman Kodak Double X film (type 7222) with a mag
netic sound strip was used. The filming speed was 24 frames
per second. The film was processed in a Smith-Picker auto
matic processor. The radiographic and the film processing
equipment are located in Shands Teaching Hospital, University
of Florida.
Each subject was filmed in a upright sitting position
with his head positioned and stabilized in the cephalostat.
A radiopaque, stainless steel ruler, with holes drilled into


59
to the alveolar ridge was defined as that frame showing the
tongue first making contact with the alveolar ridge. The
final frame for that task sequence was identified as that frame
showing the tongue in its lowest position just prior to its
elevation for the beginning of the next trial. In addition,
a third frame was identified in which the tongue was observed
to be releasing contact from the alveolar ridge. It was,
therefore, possible to define the position of the mandible at
the beginning and at the end of the three trials for this
task, as well as the range of mandibular movement throughout
each trial. The length of time (in number of frames) for the
completion of each trial and the length of time of lingual
palatal contact was defined also.
Tongue dorsum to palate. The frame identified as the ini
tiation of this nonspeech act was defined as that frame showing
the tongue contacting the palate approximately at the posterior
nasal spine. The frame showing the tongue in its lowest posi
tion just prior to elevation for the beginning of the following
trial was defined as the final frame in each trial. A third
frame showing the tongue releasing contact from the palate
was also identified. Again, it was possible to define the
position of the mandible at the initiation and completion of
each trial for this task and the range of mandibular movement
through each trial. The length of time for the completion of
each trial and the amount of time during which the tongue
was in contact with the palate was recorded also.


105
Summary: vowel-consonant-vowel production
With only a few exception, both of the experimental
conditions tended to reduce the vertical and horizontal dis
placement of the jaw for VCV's studied. The range of verti
cal and horizontal movement was reduced usually by the exper
imental conditions. The exception was the production of
/akaV where anesthesia significantly increased the range of
vertical movement. This most likely reflects the severe
reduction in the displacement of the final /a-/ by anesthesia.
With the two exceptions, differences between the values
for the anesthesia and the pressure conditions were not signi
ficant. The exceptions were a significant reduction by
pressure of the vertical displacement for the /s/ in /a.saj,
Table 19, and a significant reduction by pressure of the
range of vertical movement from the initial /a./ to the /k/
i n ¡aJf.a./ Table 21 .


13
1.
Mandibular
Condyle
4.
Upper
Synovial
Cavity
2.
Articular
Disc
(Meniscus)5.
Lower
Synovial
Cavity
3.
Temporal Bone
6.
Mandibular Fossa
7. Articular Eminence
Figure 4
Temporomandibular Articulation: Sagittal View


15
attached to the articulatory surfaces of the mandibular
fossa and to the neck of the condylar process laterally,
medially, and anteriorly. The capsule thickens laterally
into the temporomandibular ligament which will be included
in the following discussion. Except for the thickening, the
capsule is loosely organized in its lateral aspect and the
lateral aspect of the anterior wall. The medial aspect of
the anterior wall has attachments to the articular disc and
to the lateral pterygoid muscle. The medial and posterior
walls of the capsule are present but also loosely organized.
In translational movements, the condyle is pulled anteriorly
onto the articular eminence. As the meniscus is tightly
attached to the condyle while having only an elastic attach
ment posteriorly to the tympanic plate of the temporal bone,
the meniscus translates anteriorly with the condyle. How
ever, the attachment of the meniscus to the condyle is not
rigid enough to prevent movement of the condyle against the
meniscus in a horizontal plane during hinge as rotary move
ment of the mandible.
The first stage of mandibular depression is a simple
hinge action, and only the lower compartment is used as the
head of the condyle rotates along the inferior surface of
the articular disc. As the mandible is further depressed,
translation begins between the disc and the articular emi
nence resulting in forward displacement of the condyle.
There are three ligaments which participate in TMJ
articulation. These ligaments are now believed to function
in limiting jaw movement at maximum open jaw positions and


149
Table 32 continued
Vowel-Consonant-Vowel /aka/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
Thirteen:
A
7.59
7.59
7.15
Time from
B
5.81
6.03
5.81
V1 to V2
C
6.48
6.92
6.92
Mean
6.63
6.85
6.63
0.67
2
0.33
0.666
S.D.
0.52
0.45
0.41
Fourteen:
A
2.46
2.23
2.46
Time from
B
2.68
3.35
1 .79
V, to C
C
2.23
3.13
3.13
Mean
2.46
2.90
2.46
2.67
2
1.33
1.524
S.D.
0.13
0.34
0.39
Fifteen:
A
5.14
5.36
4.69
Time from
B
3.13
2.68
4.02
C to V2
C
4.24
3.80
3.80
Mean
4.17
3.95
4.17
0.67
2
0.33
0.381
S.D.
0.58
0.78
0.27


23
Within the past several years, a number of techniques
have been developed to record mandibular movement during a
variety of functions. The techniques include cinefluoro-
graphy (Jankelson et a 1., 1 953), the Case Gnathic Replicator
(Gibbs et al., 1966), the Perspex screen (Atkinson and
Shepherd, 1 955), Photoelectric Mandi bu 1ography (Gillings
and Graham, 1964), and strain gauge devices (Sussman and
Smith, 1970). There are advantages and disadvantages to each
method. Some provide information of only two planes of
movement (Photoelectric Mandibulography, cinef1uorography ,
and the perspex screen). Others are expensive to operate
(Case Gnathic Replicator) or appear to interfere with normal
mandibular movement (strain gauges). Nonetheless, with this
variety of instrumentation, an understanding of mandibular
movement is developing.
Several measurement strategies have been developed
recently to study mandibular kinesthesia. These techniques
include duplicating an interdental space (Thilander, 1961)
and several methods of assessing interdental space discrim
ination (Ringel et al., 1967; Williams and LaPointe, 1972;
and Williams et al., 1974). As a result of available
instrumentation and test methodology, there is a growing
body of literature on assessment of mandibular function.
Researchers have begun to define quantitatively mandibular
kinesthesia and mandibular function for the biophysiological
processes of the mastication, deglutition, and speech. Initial
attempts also have been made to define the sensory mechanism
responsible for


100
appeared reduced somewhat, although the amount was not
significant. The length of time required to produce /isi/
appeared not to be influenced by the anesthesia.
Pressure appeared to reduce further the amount of
vertical displacement for each of the sound elements, but
the reduction was not significant. The range of movement,
both in the vertical and horizontal dimension, were reduced
also under anesthesia, but again, the reduction from normal
did not reach significant levels. The duration of the pro
duction was significantly shorter under the pressure condi
tion.
/asa/
No significant effect was observed for comparisons of
the normal and anesthesia conditions for production of the
VCV /asa./, Table 19. The reduction of jaw displacement and
range of motion values observed for the production of /isi/
were notapparent for /asa/.
On the contrary, the application of a light pressure
significantly reduced the amount of vertical displacement
for the sound element /s/ and the range of vertical movement
from /s/ to the final la-1. In general, it was observed
throughout this sample of speech that pressure reduced the
amount of displacement and the range of movement when compared
to the values obtained under the normal condition. However,
only the two differences reported above were significant.
/ i k i /
The production of /iki/ was not influenced significantly


151
Fletcher, S. G., Process and maturation of mastication and
deglutition. ASHA REPORTS #5, SPEECH AND THE DENTOFACIAL
COMPLEX: THE STATE OF THE ART (1970).
Fletcher, S. G., Deglutition. ASHA REPORTS #6, PATTERNS OF
OROFACIAL GROWTH AND DEVELOPMENT (1971).
Fucci, D. 0. and Robertson, J. H., Functional defective
articulation: an oral sensory disturbance. PERCEPTUAL
AND MOTOR SKILLS, 33: 711-714 (1971).
Gammon, S. A., Smith, P. J., Daniloff, R. G., and Kim, C. W.,
Articulation and stress/juncture production under oral
anesthesia and masking. J. SPEECH HEARING RES., 14: 271-282
(1971).
Geissler, P. R., A preliminary report on studies of mandibular
movements in speech. DENT. PRACT,, 21: 429-432 (1971).
Gibbs, C. H., Reswick, J. B., and Messerman, T., The Case
Gnathic replicator for the investigation of mandibular
movements. Case Institute of Technology, EDC Report no. EDC
4-66-14 (1966).
Gibbs, C. H., Messerman, T., Reswick, J. B., and Derda, H.,
Functional movements of the mandible. J. PROSTH. DENT., 26:
604-620 (1971).
Gibbs, C. H. and Messerman, T., Jaw motion during speech.
ASHA REPORTS #7, OROFACIAL FUNCTION: CLINICAL RESEARCH IN
DENTISTRY AND SPEECH PATHOLOGY (1972).
Gillings, B. R. D., Jaw movements in young adult men during
speech. J. PROSTH. DENT., 29: 567-576 (1973).
Gillings, B. R. D. and Graham, C. H., Photoelectric method
for recording jaw movements. J. DENT. RES., 43: 305 (1964).
Gray, H., ANATOMY OF THE HUMAN BODY, Philadelphia, Pa.: Lea
and Febiger (1959).
Greenfield, B. E. and Wyke, B., Reflex innervation of the
temporomandibular joint. NATURE, 211: 940-941 (1966).
Hansen, G., Effect of jaw restriction on speech intelligi
bility. WRIGHT AIR DEVELOPMENT CENTER TECHNICAL REPORT,
52: 223 (1952).
Hixon, T. J. and Hardy, J, C,, Restricted motility of the
speech articulation in cerebral palsy. J, SPEECH HEARING
DIS. 29; 293-306 ( 1 964) ,
Horii, Y., House, A. S., Li, K. P,, and Ringel, R., Acoustic
characteristics of speech produced without oral sensation.
J. ACOUST. SOC. AMER. 51: 1 06-1 28 (1 972).


21
on this task, which has been suggested to involve intra-oral
movements similar to those in speech production, is severely
disrupted by mandibular block anesthesia (Schliesser and
Coleman, 1968 and Thompson, 1969).
A positive relationship between speech skills and oral
stereognosis has been established also (Moser et al., 1967;
Ringel et al , 1968; Weinberg 1 970; Fucci and Robertson,
1971; and McNutt, 1973). These studies have demonstrated that
articulatory defective individuals without any known structural
or organic pathologies perform poorer on tasks of oral stere
ognosis than do their normal speaking counterparts. Further
evidence of a positive relationship between speech skills and
oral stereognosis is offered by Bishop et al. (1973). These
researchers compared the performance of manually educated
deaf individuals and to normal hearing speakers on a task of
oral stereognosis. The experimental group made more errors
on this task as well as making different types of errors as
compared to the other two groups. The authors suggested that
orosensorimotor functions develop, in part, through the prac
tice of speech skills.
A discussion of sensory disruption is necessarily
followed by a discussion of feedback systems. The researchers
who initially investigated articulation under nerve block
anesthesia assigned monitoring abilities for any uneffected
articulatory events to other channels, presumably undisturbed
by the anesthesia. This reflects the view that all articula
tory activities are monitored by some sensory channel. This


67
performance during attempts to duplicate the standard position
ten times under the three conditions. Included in Table 1 are
means and standard deviations for the group of four subjects.
Anesthesia appeared not to make it more difficult for the
subjects to find the standard jaw opening; the mean for the
normal condition is 6.00 mm, while the mean for the anesthesia
condition is 5.50 mm. However, three subjects (A, B, and D)
of the four found it easier to duplicate the standard position
when a light pressure was applied to the left TMJ. This is
also reflected in a reduced mean performance score for the
pressure condition; X = 4.0 mm.
The mean difference in jaw position from the standard
position, as well as standard deviation, is presented in Table
2. The means obtained for each of the three conditions sug
gest that neither the anesthesia nor the anesthesia and pres
sure had an affect on the ability of the subjects to dupli
cate the standard. The means vary from a 3.25 mm for the
anesthesia and pressure condition to a 3.65 mm for the normal
condition.
Analysis of individual subject means presents somewhat
conflicting results. The ability of subjects A and C to du
plicate the standard was impaired somewhat by the anesthesia
condition. However, performance was improved by pressure to
the opposite TMJ only for subject A. Subject D's performance
also was improved by pressure, however, his performance under
anesthesia was better than under the control condition. More
over, the performance of subjects A and C was impaired by


34
these two areas is in close agreement and can be summarized
and discussed together. Another current investigation of
speech and masticatory function (Gibbs and Messerman, 1972)
has been discussed earlier and will not be included here.
There seems to be a general agreement among researchers
that jaw position is lower for vowel sounds (/o>/ ,/:>/), diph
thongs (/a I /), and back consonant (/k/,/g/) production and is
more elevated for high vowels (/i/,/u/) and front consonant
(/p/,/s/) production. The mandible has been observed to dis
place posteriorly as it displaces interiorly. Kent and Moll
(1972) and Owens (1973) have explained that this is due to
the hinge-type movements of the condyle for the mandible's
speech movements. It is also recognized that adjacent pho
nemes may cause mandibular position to vary slightly for any
one phoneme. Geissler (1971) has demonstrated further that
mandibular movement may vary with speaking rate, becoming
less as speaking rate increases. Geissler (1971) and Gillings
(1973) have observed also that while mandibular position for
closed sounds tends to be fairly consistent from individual
to individual, the position of the mandible varies from in
dividual to individual for open sounds. Although there is
obviously room for continued research in this area, it is
apparent that specific mandibular positions are responsible
for specific phonetic productions.
Other areas of mandibular dynamics are also currently
under investigation. New research is providing information
that is beginning to explain the complex interplay between
the dynamic mandible and other articulators including the lips


57
2. Measurement of vertical mandibular displacement noted
in an upward or negative (-) direction.
3. Measurement of horizontal mandibular displacement noted
in a backward or positive (+) direction.
4. Measurement of horizontal mandibular displacement noted
in a forward or negative (-) direction.
Figure 12
Defined Measurements of Mandibular Displacement
and Associated Positive and Negative Values


94
Table 15
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /el/
Measures Condition Pairs
Vertical Displacement
Normal/
Anesthesia
Normal/
Anes thesia-
Pressure
Anesthesia/
Anesthesia-
P res s ure
Initial
10.72/10.61
10.72/8.82*
10.61/8.82*
Final
5.14/5.14
5.14/4.30
5.14/4.30
Horizontal Displacement
Initial
5.81/5.25
5.81/5.30
5.25/5.30
Final
3.74/3.74
3.74/3.85
3.74/3.85
Ranqe of Vertical Movement
5.70/5.53
5.70/5.58
5.53/5.58
Ranqe of Horizontal Movement
2.34/1.73
2.34/1.62*
1.73/1 .62
Duration of Production
8.42/6.83
8.42/7.50
6.83/7.50
p-c.05


CHAPTER FIVE
DISCUSSION
The sensory receptors and the role they play in
monitoring and regulating intelligible speech is not yet
clearly understood. There have been a number of studies
whose purpose it was to study mandibular motion during
speech function, to define parameters of mandibular kines
thesia, and to determine what structures are responsible
for perceiving and transmitting information of mandibular
kinesthesia or mandibular position sense. The work of
Thilander (1961) and her colleagues (Ransjo and Thilander,
1963 and Larsson and Thilander, 1964) implicated the
sensory receptors in the TMJ and it's ligament as, at least,
having partial responsibility for monitoring perception of
mandibular position. The present study was designed to
investigate the role of the sensory mechanism of the TMJ for
monitoring the movement and posturing of the mandible during
selected speech and nonspeech tasks. Specifically, the
purpose was first to assess the effect of a unilateral
anesthetization of the auriculotemporal nerve on jaw function
and secondly to assess subsequently the effects of a light
pressure to the contralateral TMJ capsule.
106


BIBLIOGRAPHY
Abbs, J. A., The influence of the gamma motor system on jaw
movements during speech: A theoretical framework and some
preliminary observations. J. SPEECH HEARING RES., 16:
175-200 (1973).
Abbs, J. A. and Netsell, R., An interpretation of jaw
acceleration during speech as a muscle forcing function,
J. SPEECH HEARING RES., 16: 421-425 (1973),
Abbs, J. A., Netsell, R., and Hixon, T. J., Variations in
mandibular displacement, velocity, and acceleration as a
function of phonetic context. J. ACOUST. SOC. AMER.,
51:89 (1972).
Atkinson, H. F. and Shepherd, R. W., TMJ disturbances and
the associated masticatory patterns. AUST. DENT. 0.,
16: 219-222 (1961).
Bishop, M. E., Ringel, R. L., and House, A. S., Orosensory
perception, speech production, and deafness. J. SPEECH
HEARING RES., 16: 257-266 (1973).
Black, J., The effects of delayed sidetone upon vocal rate
and intensity. J. SPEECH HEARING RES., 16: 56-60 (1951).
Borden, G. J., A phonetic analysis of the speech of four-
year-old boys with mandibular nerve block. A paper
presented at the convention of the American Speech and
Hearing Association (1973).
Cole, R. M., Speech. ASHA REPORTS #6, PATTERNS OF OROFACIAL
GROWTH AND DEVELOPMENT (1971).
Enlow, D. H., The growth and development of the craniofacial
complex. In W. C. Grabb, S. W. Rosenstein, and K. R. Bzoch,
(Eds.) CLEFT LIP AND PALATE, Boston: Little, Brown (1971),
Fairbanks, G., Systematic research in experimental phonetics.
I. A theory of the speech mechanism as a servosystem. J.
SPEECH HEARING DIS., 19: 133-140 (1954).
Fairbanks, G., Selected vocal effects of delayed auditory
feedback. J. SPEECH HEARING DIS., 20: 333-346 (1955).
150


117
sequences was a reduction in the range of vertical movement.
Although it was significant only for the production of ¡a- IW,
it supports previous observations that pressure restricts
jaw movement. Notice also that /a.ko/ required the greatest
amount of jaw opening.
Effect of Pressure: Summary
These data have been interpreted to suggest that a
light pressure (1-2 pounds per square inch) applied to one
TMJ capsule reduces the amount of jaw opening and the range
of jaw movement throughout the production of a sequence of
sounds. Several explanations of this phenomena may be
forwarded. The findings of Thilander and her colleagues,
as to the restorative powers of pressure, might be reinter
preted. Larsson and Thilander (1964) and Ransjo and Thilan
der (1963) reported a reduction in the range of jaw opening
values when pressure was applied to a TMJ capsule contra
lateral to an anesthetized one. The previous researchers
may have observed a restriction in the opening movement of
the mandible. Since it was observed that pressure reduced
opening significantly when the jaw displacement required
exceeded 10.00 mm, Table 22, it is suspected that pressure
mechanically restricted the translatory motion of the condyle.
A second explanation is that pressure, even a light
pressure, might have displaced the condyle medially. In
which case, pain might have been generated by traction on
the nerve endings in the richly innervated lateral parts of
the capsule (Storey, 1968). The reduction in the opening


Table 27
Diphthong /aU/
Measure
Subject
Normal
One:
A
16.53
Vertical
B
8.49
Jaw Posi-
C
10.27
tion for
D
16.08
Initial
Mean
12.84
Frame
S.D.
2.03
Two:
A
4.69
Horizontal
B
7.15
Jaw Posi-
C
5.36
tion for
D
7.37
Initial
Mean
6.14
Frame
S.D.
0.66
Three:
A
13.40
Vertical
B
2.46
Jaw Posi-
C
0.00
tion for
D
9.38
Final
Mean
6.31
Frame
S.D.
3.09
Four:
A
4.02
Horizontal
B
5.36
Jaw Posi-
C
5.36
tion for
D
4.91
Final
Mean
4.91
Frame
S.D.
0.32
Five:
A
3.13
Range of
B
6.03
Vertical
C
10.50
Movement
D
6.70
Mean
6.59
S.D.
1 .52
Condition
Anesthesia/
Anesthesia Pressure
16
.08
10
.94
6
.70
5.
.14
13
.18
7.
.82
13.
.40
13.
.40
12
.34
9,
.32
1 .
.99
1 .
.80
6.
.48
6
.25
5
.58
5.
.81
5.
.14
4.
.02
6.
.25
7.
, 1 5
5,
.86
5.
.81
0.
.31
0.
.66
12.
.95
9,
.38
0.
.45
2,
.01
-0,
.45
-1 .
. 34
7
.59
8.
. 26
5.
.14
4.
.58
3,
.16
2.
.55
5.
.14
4.
.91
4.
.47
5.
,36
4.
.69
3.
.80
4,
.24
5.
.58
4.
.63
4.
.91
0.
,19
0.
.40
3,
13
1 .
,79
6.
.48
3.
13
14.
07
9.
.16
5.
81
5 .
14
7.
37
4.
80
2.
35
1 .
61
Summary:
Amalysis of
Repeated Measures
SS df MS F
193.50 2 96.75 15.677*
1.72 2 0.86 0.397
41.72 2 20.86 5.179*
1.39 2 0.69 0.580
92.67 2 46.33 10.884*


43
succession. The distance between the upper and lower central
incisors was measured and recorded by the examiner for each
of the ten subsequent trials. The subject was not informed
as to the accuracy of his responses.
Interdental thickness discrimination
This task required each subject to make judgements
concerning the thickness of blocks placed in pairs, one at
a time, between the maxillary and mandibular central incisors.
The instrumentation used in this task, which was developed
by Williams and LaPointe (1972), is illustrated in Figure
8 and consists of 21 acrylic blocks, each 4.5 cm long by
1.5 cm wide. The thickness of the blocks varies in 1 mm
increments and ranges from 10 to 25 mm. In performing this
task, each subject was asked to judge whether the second
block of each pair was "the same," "thicker," or "thinner"
than the first block of the pair. The first block in
each pair presentation was considered the "standard" and was
always 10 mm thick. The second block presented in each pair
was a different thickness. A modified "method of limits"
procedure, with two ascending runs, was used to arrive at
each subject's difference limen. A "run" was defined as
the presentation to the subject of as many different pairs
of blocks as necessary until two consecutive correct judge
ments were made.
Discrimination of lateral mandibular positioning
Each subject's ability to discriminate differences in


133
Table 26 continued
Diphthong /el/
Measure
Condition
Anesthesia/
Sub.ject Normal Anesthesia Pressure
Summary:
Analysis
Repeated
SS df
Six:
A
1 .
.79
1 ,
.12
0.
.89
Range of
B
3.
.35
2.
.23
1 .
.79
Horizonta 1
C
1 ,
.12
1 ,
.56
1 .
.34
Movement
D
3,
.13
2.
.01
2.
.46
Mean
2,
.35
1 .
.73
1 .
.62
S.D.
0,
.53
0.
.25
0,
.33
Seven:
A
6.
,03
3.
,57
4.
.47
Time from
B
4.
.47
4.
.69
4.
.24
Initial
C
6,
.03
5.
.58
5.
.36
to Final
D
6.
,03
4,
.47
6.
.03
Frame
Mean
5.
.64
4.
.58
5.
.02
S.D.
0.
. 39
0.
.41
0,
.41
of
Measures
MS F
.08 3.571*
.58 3.976*


80
Table 11
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination
Condition
Subject
Trial
Normal
Anes thetized
Anesthetized and Pressure
A
1)
5.0 gms
14.0 gms
5.0 gms
2)
6.0
6.0
5.0
B
1)
13.0
4.0
11.0
2)
11.0
4.0
12.0
C
1)
7.0
5.0
2.0
2)
8.0
6.0
6.0
D
1)
4.0
6.0
12.0
2)
7.0
12.0
16.0
Means
7.62 gms
7.12 gms
8.62 gms
Standard
Deviation
3.01
3.75
4.47


152
Ingervall, B., Bratt, C. M,, Carlsson, G, E., Helkimo, M.,
and Lantz, B., Positions and movements of the mandibular
and hyoid bone during swallowing. A ci neradiographic study
of swallowing with and without anesthesia of the TMJ's.
ACTA ODONT. SCAND., 29: 549-562 0971).
Ingervall, B., Bratt, C. M., Carlsson, G. E., Helkimo, M. ,
and Lantz, B., Duration of swallowing with and without
anesthesia fo the temporomandibular joints. SCAND. J. DENT,
RES. 80: 189-196 [1 972) ,
Jankelson, B., Hoffman, G. M., and Hendron, J. A., The
physiology of the stomatagnathic system. J. AMER, DENT.
ASSN., 46: 375-386 (1953).
Kawamura, Y., Neuromuscular mechanism of jaw and tongue
movement. J. AMER. DENT. ASSN., 65: 545-551 (1961).
Kawamura, Y. and Watanabe, M., Studies on oral sensory
threshold. MEDICAL J. OF OSAKA UNIVERSITY, 10: 291-301 (1960).
Kent, R. D., Some considerations in the cinef1uorographic
analysis of the tongue movements during speech. PHONETICS,
26: 16-32 (1972).
Kent, R. D., Is the seriation of speech movements governed by
motor programs or feedback? A paper presented at the annual
convention of the American Speech and Hearing Association,
Detroit, Michigan (1973).
Kent, R. and Moll, K. Cinefluorographic analysis of selected
lingual consonants. J. SPEECH HEARING RES., 15: 453-473
(1 972) .
Keppel G., DESIGN AND ANALYSIS, Englewood Cliffs, New Jersey:
Prentice-Hall, Inc. (1973).
Larsson, L. E. and Thilander, B., Mandibular positioning:
the effect of pressure on the joint capsule. OCTA NEUROL.
SCAND., 40: 131-143 ( 1964) .
Lee, B. S., Effects of delayed speech feedback. J. ACOUST.
SOC. AMER., 22: 824-826 (1950).
MacNeilage, P. F., Closed-loop control of the iniatiation of
jaw movements for speech. A paper presented at the annual
convention of the Accoustical Society of America (1970).
Mahan, P. E., Anatomy of the stomatagnathic system. In S, D,
Tylman (Ed.) THEORY AND PRACTICE OF CROWN AND FIXED PARTIAL
PROSTHODONTICS (BRIDGE), St. Louis, Mo: C. V. Mosby (1967).


121
utilized in this study. It was suggested that the intra-
capsular injection procedure utilized by Thilander and her
colleagues resulted in a more complete blocking of the
sensory receptors or possibly that a bilateral block of
the auriculotemporal nerve might disrupt more consistently
subjects' performance.
The results of this study demonstrate further that a
light pressure (1-2 pounds per square inch) consistently
reduces the amount of jaw opening for those speech tasks
requiring a jaw displacement of more than 10 11 mm. These
data were interpreted to suggest that either the sensation
of pressure or pain limits the translatory motion of the
condyle and hence mandibular displacement. Further, these
data suggest that the reduction in range of jaw positions
caused by unilateral intracapsular injection of anesthesia
and unilateral TMJ dysfunction was the result of a mechan
ical restriction of condylar translatory motion and not im
proved sensation of mandibular position.
Further investigation might explore the clinical
application of pressure to the TMJ of individuals who
demonstrate velopharyngeal incompetency with concomitant
aberrant jaw positioning; specifically adults with bulbar
or flaccid dysarthria. These patients have been observed
to tilt their heads back during speech attempts (Marshall
and Jones, 1971) and to utilize an exaggerated mouth opening
during speech production by this author. It has been
hypothesized that this is a compensatory action to make the


62
of mandibular motion through each trial. The length of time
required to complete each trial was recorded also.
Sentence
Seventeen frames depicting the production of seventeen
speech phonemes were selected from the sentence, "In the
evening Connie watches TV with me." The selected phonemes are
represented by the underlined graphemes in the sentence below.
IN THE EVENING CONNIE WATCHES TEE
1 23 4567 8 9 10 1112
V E E W I TJH M E .
13~T4 15 16 17
The definitions for identifying these phonemes within the
sentence from cinef1uorographic recordings have been described
in detail by Owens (1973) and have been duplicated here for
convenience.
1. The /5/ of the" was defined as the 1ingual-dental contact
immediately following the 1 ingua1-alveolar contact required
for the production of the phoneme /n/ of "In.11.
2. The /i/ of "evening" was defined as the highest point of
lingual elevation preceding the labial-dental contact re
quired for the production of the phoneme /v/ of "evening".
3. The /v/ of "evening" was defined as the 1abi a 1-dental
contact necessary for its production.
4. The /ij/ of "evenimj." was defined as the part of lingual-
velar contact between the back of the tongue and the velum
while the velum was down.
5. The /k/ of "Connie" was defined by the 1 ingua1-velar contact
required for its production while the velum was


97
Table 17
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /ol/
Measures Condition Pairs
Vertical Displacement
Initial
Final
Norma 1/
Anesthesia
8.54/8.43
5.31/5.36
Normal/
Anesthesia-
Pressure
8.54/7.37
5.31/4.52
Anesthesia/
Anesthesia-
Pressure
8.43/7.37
5.36/4.52
Horizontal Displacement
Initial
Final
5.53/5.42
5.02/5.31
5.53/5.86
5.02/5.53
5.42/5.86
5.31/5.53
Ranqe of Vertical Movement
3.40/3.30
3.40/3.07
3.30/3.07
Ranqe of Horizontal Movement
1 .29/0.95
1 .29/1.06
0.95/1.06
Duration of Production
6.83/6.42
6.83/5.92
6.42/5.92
p<. 05


16
to provide proprioceptive input to the central nervous
system via their Golgi tendon organs. These ligaments are
illustrated in Figures 6 and 7.
The temporomandibular ligament is comprised of two short
bundles, one anterior to the other. As noted earlier, this
ligament is a thickened portion of the articular capsule. The
ligament is attached superiorly to the zygomatic arch and
interiorly to the lateral, posterior surface of the condylar
process.
The sphenomandibular ligament is a remnant of Mechel's
cartilage. The ligament arises from the angular spine of the
sphenoid bone and spreads fanlike downward and outward
finally attaching to the mandible ar the lingula of the man
dibular foramen.
Lastly, the stylomandibular ligament extends from near
the apex of the styloid process of the temporal bone to the
angle and posterior border of the ramus of the mandible.
Sensory innervation to the TMJ capsule is supplied
primarily by the auriculotemporal nerve of the mandibular
branch of the Trigeminal nerve. Small slips of the masseteric
and posterior deep temporal nerve also supply the capsule
anteriorly.
Histological studies have provided further information
regarding the sensory innervation of the capsule. Thilander
(1961) demonstrated that the posterior and lateral aspects
of the capsule are the most richly innervated, while the
anterior and medial aspects are sparsely innervated and the
articular disc lacks any sensory innervation. Thilander found


Figure 10
Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination


42
Three of the perceptual tasks were designed to assess
subjects' ability to discriminate between pairs of mandibular
positions in the three planes of space. These tasks include
discrimination of pairs of positions in the vertical dimension
(interdental thickness discrimination), in the lateral dimen
sion (discrimination of lateral mandibular positions), and in
the anterior-posterior dimension (discrimination of anterior-
posterior mandibular positions).
The fifth and final perceptual task required subjects
to make judgements between pairs of weighted capsules placed
between the maxillary and mandibular incisors. This task was
included in an attempt to either implicate or rule out the
sensory mechanism of the TMJ as having a role in interdental
weight discrimination. Tasks were presented in a random order
Duplication of an interdental space
This task required each subject to reproduce an arbi
trarily determined, comfortable open mouth position somewhere
between the closed or physiologic rest position and a maximum
open mouth position (Thilander, 1961). The amount of mouth
opening was determined by measuring the distance between the
upper and lower central incisors with a plastic ruler.
Measurements were taken to the nearest millimeter. The ruler
was shaped so that one end would fit over the incisal edge of
the lower incisors to insure standard measurement conditions.
Each subject was instructed to remember the initial mouth
or jaw open position and then to attempt to replicate this
same position ten times in close


141
Table 30
Vowel-Consonant-Vowel /aso./
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Sub.iect
Normal
Anesthesia
Pressure
SS
df
MS
F
One :
A
3.80
3.13
3.80
Vertica1
B
5.58
7.59
7.59
Jaw P o s i -
C
10.05
8.93
7.59
tion for
Mean
6.48
6.55
6.63
0.22
2
0.11
0.017
V1
S.D.
1 .86
1 .75
1 .44
Two:
A
6.03
5.36
6.03
Horizontal
B
5.36
5.58
4.24
Jaw Posi-
C
4.69
4.69
4.91
tion for
Mean
5.36
5.21
5.06
0.89
2
0.44
0.299
V1
S.D.
0.39
0.27
0.52
Three:
A
-2.01
-2.01
-1 .34
Vertical
B
-2.01
-2.01
-2.01
Jaw Posi-
C
1.12
1.12
1.79
tion for
Mean
-0.97
-0.97
-0.52
2.67
2
1 .33
8.000*
C
S.D.
1.04
1 .04
1.17
Four:
A
2.68
2.46
2.90
Horizonta 1
B
3.35
3.35
3.35
Jaw Posi-
C
1.34
0.89
1.34
tion for
Mean
2.46
2.23
2.53
0.96
2
0.48
1 .529
C
S.D.
0.59
0.72
0.61
Five:
A
3.35
2.23
3.13
Vertica1
B
0.00
0.89
1 .56
Jaw Posi-
C
9.16
6.70
6.48
tion for
Mean
4.17
3.27
3.72
8.00
2
4.00
0.483
V2
S.D.
2.68
1 .76
1 .45
Six:
A
6.25
4.91
5.58
Horizontal
B
4.47
5.14
4.47
Jaw Posi-
C
4.47
3.35
4.24
tion for
Mean
5.06
4.47
4 76
3.56
2
1.78
1 .524
S.D.
0.59
0.56
0.41


4
deposition and resorption predominantly in the posterior
and superior direction. The overall growth of the mandible
is associated with regional growth areas, which include
virtually all of the inner and outer surfaces of the mandi
ble. These areas of growth include the neck of the condyle,
the coronoid process, the lingual tuberosity, the trihedral
eminence, and the chin. The regional growth movements are
concerned with a continuous process of relocation in which
the various local parts become shifted progressively in order
to maintain constant positions relative to the remainder of
the growing enlarging mandible as a whole.
Adult Mandible
As noted earlier, the mandible consists of a horseshoe
shaped body, which continues upward and backward into the
mandibular ramus. The ramus ends in two processes, the con
dylar and the coronoid. Figures 1 and 2 illustrate the lat
eral and medial aspects respectively of the adult mandible.
The mental symphysis joins the left and right mandibu
lar bodies. Externally, it appears as a faint ridge. The
ridge divides inferiorly and encloses a triangular eminence,
the mental protuberance, which is depressed in the center,
but is raised on either side to form the mental tubercles.
The incisive fossa are the depressions lateral to the sym
physis and just below the incisor teeth. The incisive fossa
are the origin of the mentalis and a small portion of the
orbicularis oris muscles. The mental foramen is found below
the second premolar tooth, midway between the inferior and


93
Table 14
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /a I /
Measures Condition Pa i rs
Normal/ Anesthesia/
Normal/ Anesthesia- Anesthesia-
Vertical Displacement Anesthesia Pressure Pressure
Initial
11.22/11.06
1 1 22/8.44*
1 1 .06/8.44*
Final
4.80/4.13
4.80/3.68
4.13/3.68
Horizontal Displacement
Initial
5.14/5.31
5.14/5.42
5.31/5.42
Final
4.64/4.41
4.64/4.42
4.41/4.42
Ranqe of Vertical Movement
6.36/6.98
6.36/4.75*
6.98/4.75*
Ranqe of Horizontal Movement
1.23/1.79
1.23/1.29
1.79/1.29
Duration of Production
7.83/6.42*
7.83/7.25
6.42/7.25
p. 05


CHAPTER THREE
METHODS AND PROCEDURES
Subject Selection
Four young adult males served as subjects. Their ages
range from 22 years, 4 months to 29 years, 4 months with a
mean age of 25 years, 11 months. The individuals who served
as subjects possessed all of their natural central incisors,
had an Angle Class ONE occlusion with a normal bite. None of
the subjects complained of any current or past history of TMJ
dysfunction. All subjects were monolingual speakers of the
General American Dialect and had no articulation or voice
disorders.
Experimental Tasks
Perceptual Measures
The perceptual measures utilized in this study were de
signed to assess subjects' abilities to discriminate between
differences in mandibular positions and to discriminate be
tween differences in weights placed between the maxillary and
mandibular incisors. The first perceptual measure required
each subject to duplicate an arbitrary interdental space.
This task was included as an attempt to replicate and verify
Thilander's initial research in the area of TMJ anesthetiza
tion.
41


46
mandibular position lateral to a midline position was
assessed using an instrument designed and developed by
Williams and LaPointe (1973). This instrument is illustrated
in Figure 9. The device consists of two interlocked, sliding
plates that are adjustable in one-half millimeter increments
by means of a thumb screw which allows for controlling the
position of one plate in relation to the other. The v-shaped
wedge on the upper plate was positioned in the space between
the two maxillary incisors. The subject then moved his jaw
about until the lower plate seated between the space of the
two mandibular incisors. This task required the subject to
make judgements concerning the lateral position of his lower
jaw as determined by the positions of the lower wedge, which
were presented to him, in pairs, one at a time. Each subject
was asked to judge whether the second position was "the same,"
"to the left," or "to the right" of the first position. The
first position, considered the "standard," was always that
position where upper and lower wedges were in a vertical line.
The second position in each pair was a different position
either to the left or to the right of midline. Again, a
modified "method of limits" procedure, with two ascending runs,
was used to arrive at each subject's difference limen in a left
or right direction. As in the interdental thickness task, a
"run" was defined as the presentation of as many different
pairs of wedge settings as necessary until two consecutive
judgements were made.


61
Diphthongs: /al/, /el/, /aU/, and /jl/
The initial and the final frames representing the pro-
duction of each of the diphthongs were identified as those
frames showing optimal tongue or lip placement for the produc
tion of the respective vowels.
The frames identified as the production of the vowels
/a/, /e/, and /o/ as they occur in the initial positions of
the diphthongs /al/, /el/, and /jl/ respectively were defined
as those frames showing the tongue in its 1owest position
prior to elevation for the production of the second vowel in
the diphthong. The frame identified as the production of the
vowel /a/ in the initial position of the diphthong /aU/ was
defined as that frame showing the lip in its lowest position
prior to its elevation for rounding in the production of the
second vowel in the diphthong.
The frames identified as the production of the vowel
/I/ as it occurs in the final position of the diphthongs /al/,
/el/, and /jI/ were defined as those frames showing the
tongue in its highest position prior to its lowering for the
initiation of the next trial. The frame identified as show
ing the production of the vowel /U/ as it occurs in the final
position of the diphthong /all/ was defined as the frame show
ing the lower lip in its highest position prior to its lowering
for the beginning of the next trial.
It was possible, therefore, to define the vertical and
horizontal position of the mandible at the beginning and at
the end of the production of each trial as well as the range


47
Discrimination of anterior-posterior mandibular positions
Each subject's ability to discriminate between mandibular
postions anterior to a position in which the maxillary and the
mandibular incisors are in a vertical line was assessed
utilizing the same instrument which was used in assessing
lateral discrimination ability. For the anterior-posterior
task, however, the inverted v-shaped wedge on the upper plate
(shown at left of instrument in Figure 9) was placed over
the maxillary incisors seated in the wedge on the lower plate.
This task required the subject to make judgements concerning
the anterior position of his jaw as determined by the positions
of the lower wedge which were presented to him in pairs, one at
a time. Each subject was asked to judge whether the second
position of each pair was "the same," "forward," or "backward
compared to the first position. The first position, again
considered the "standard," was always that position where the
upper and lower wedges were in a vertical line. The second
position of each pair was a different position anterior to the
first. The same modified "method of limits" procedure, with
ascending runs, was used to determine each suject's threshold
of detecting differences in jaw positions in the anterior
direction. A "run" was defined as it had been for the pre
ceding tasks.
Interdental weight discrimination
This task was used to assess each subject's ability to
discriminate between pairs of weighted capsules. The task
utilized the instrumentation shown in Figure 10. The


102
by the experimental procedures utilized in this study,
Table 20. Some small reductions were observed for horizon
tal displacement of each sound element and in the length
of production, however, none of these values approached
significanee.
/a. kg/
The vertical displacement for the final /a-/ was sig
nificantly reduced under the anesthesia condition, Table 21.
The vertical displacement for the sound element /k/ was re
duced also, but not significantly. Vertical displacement for
the initial /a./ was greater under anesthesia. Again, the
difference was not significant. The range of vertical move
ment from the initial /a./ to the final /a-/ and from the ini
tial /a/ to the /k/ were significantly greater under anesthe
sia. This most likely reflects the reduction in the dis
placement for the /k/ and final /a./. Horizontal displace
ment and horizontal range of movement were reduced also by
anesthesia, but not significantly.
Vertical displacement for the final /a./ was signifi
cantly less under the pressure condition when compared to the
normal condition. The range of vertical movement from the
initial /cl/ to final /a./ and from the /k/ to final /a-/ was
reduced significantly under pressure. Further, pressure
significantly reduced the range of vertical movement from the
initial /a./ to the /k/ when compared to the anesthesia
condi ti on.


APPENDIX
Summary of Raw Data and Analysis of Repeated Measures
This Appendix presents a summary of the raw data for
each subject for the two tasks of nonspeech oral movement,
the four tasks of diphthong production, and the four tasks
of vowel-consonant-vowel production. The mean and standard
deviation are presented for each condition. In addition,
a summary of analysis of repeated measures including: sum
of squares, degrees of freedom, mean square, and F statistic
for each tasks is provided. An asterisk (*) following an
F value denotes p<.05.
123


113
of large diameter (greater than 4/<() fibers (Thilander,
1961). These larger diameter fibers are more prone to carry
proprioceptive information. It might also be suspected that
bilateral blocking of the auriculotemporal nerve would pro
duce more serious disruptions of mandibular position sense.
However, further study is needed.
Further, the initial onset of jaw movement has been
attributed to rapidly adapting Type II mechanoreceptors,
which are quite numerous in the TMJ capsule. Type II
mechanoreceptors discharge briefly at the onset of joint
movement (Greenfield and Wyke, 1966). If this were true,
we would have expected much more variation between conditions
for the tasks such as a duplication of an interdental space
and in the initial jaw position for speech tasks. However,
only the results of vertical positioning for the production
of connected speech support this, Figure 13. For that task,
the mandible was displaced more for the starting position
under TMJ anesthetization than for the normal condition.
Jaw position was stabilized then by the slowly adapting motor
unit discharge of the Type I receptors responding to the
stretch of the muscle spindles in the mandibular elevators,
(Moyers, 1973).
We cannot rule out the possibility that the muscle
spindles provide sensory feedback important for jaw posi-
ioning. Thilander (1961) suggested that a more complete
disruption of the subjects' jaw position sense did not occur
because of proprioceptive feedback from the muscles of


8
of the digastricus The mylohyoid line extends posteriorly
and superiorly from the interior part of the symphysis. The
mylohyoid originates along this line. The superior pharyn
geal constrictor originates, in part, from the posterior por
tion of the line near the alveolar margin.
The medial surface of the ramus is marked near its
center by the mandibular foramen for the entrance of the in
ferior alveolar vessels and nerve. The mylohyoid groove
runs obliquely inferiorly and anteriorly from the foramen
and houses the mylohyoid vessels and nerve. The angle of
the mandible provides attachments for the masseter laterally
and the internal pterygoid on its medial aspect. The internal
aspect of the ramus also provides attachments for several
ligaments. The attachments and ligaments will be discussed
later as a group.
Mandibular Musculature
The mandible is influenced in its movements and posi
tioning by all of the muscles that attach to it. Further
more, all mandibular muscles are active in all movements of
the mandible as their roles shift from movers to balancers
to holders (Sarnat, 1964). Two groups of muscles are of
prime concern. They are the muscles of mastication and the
suprahyoid muscles. Two other group of muscles are of se
condary importance. They are the infrahyoid muscles, which
serve to stabilize the hyoid bone and the cervical column
and the post vertebral muscles, which serve to stabilize the
cranium, (Sicher and DuBrul, 1970 and Perry, 1973). The


LIST OF FIGURES
FIGURE PAGE
1 Mandible: Left Lateral Aspect ..5
2 Mandible: Left Medial Aspect 7
3 Muscular Control of Mandibular Movement. 10
4 Temporomandibular Articulation: Sagittal View. ...13
5 Temporomandibular Articulation: Frontal View 14
6 Temporomandibular Ligament: Lateral View 17
7 Sphenomandibular and Stylomandibular Ligaments:
Medi al View 18
8 Acrylic Blocks for Assessing Interdental
Thickness Discrimination 44
9 Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination 45
10 Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination 48
11 Cephalostat and Pressure Device 53
12 Defined Measurements and Their Associated
Positive and Negative Values 57
13 Means, Ranges, and S.D.'s of Vertical Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4) 83
14 Means, Ranges, and S.D.'s of Horizontal Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4) 85
v i i i


51
Diphthongs: /al/, /el/, /aU/, /3l/
A diphthong has been defined by Wise (1957) as two
vowels pronounced in a quick, unbroken succession within a
syllable, and connected by a gliding series of unrelated
sounds. Four diphthongs were included in the speech sample
because of their unique arrangement consisting of a low or
mid vowel and a high vowel. Production of these diphthongs
requires considerable mandibular and lingual movement with
minimal 1ingual-palatal contact. The diphthongs used in this
study were: /al/, as in the word "high," /el/, as in the word
"hay," /OI/, as in the word "hoist," and /aU/, as in the word
"how. As for production of the VCV combinations, each of the
diphthongs were spoken three times by each subject for each of
the three conditions.
Connected speech
The sentence "In the evening Connie watches TV with me."
was selected as a representative sample of ongoing speech. It
contains a distribution of front and back consonants, such as
/t/ and /k/, as well as vowels which represent the extremes of
the vowel triangle, such as /i/ and /a-/. Each subject was
instructed to repeat the sentence in their usual speaking
manner relative to such factors as intensity, duration, and
inflectional patterns.
Experimental Procedures
Two experimental conditions were developed for this
study. The experimental conditions were: 1) unilateral anes
thetization of the right auriculotemporal nerve (innervating
the right TMJ)


95
The time required to produce /el/ was reduced significantly
by anesthesia.
Diphthong: /aTT/
Paired values for the measures of /all/ production are
presented in Table 16. The effects of the experimental pro
cedures are similar to those found on the preceding task of
/a I/ and /el/ production. Pressure had a statistically sig
nificant effect towards reducing vertical jaw displacement
for the starting position. The application of pressure also
reduced the vertical displacement for the ending mandibular
position. Horizontal displacement did not vary significantly
between any of the condition pairs.
The range of vertical excursion of the mandible also
was reduced significantly by the application of pressure.
However, the range of horizontal movement was not altered
significantly by either of the experimental conditions.
Neither was the amount of time required to produce the diph
thong altered by the experimental procedures.
Diphthong: /a I/
Condition pairs for the production of /a I/ are listed
in Table 17. No significant differences existed for any of
the paired values for the production of this diphthong.
However, a trend for pressure to reduce the vertical posture
of the mandible for the initial and final jaw positions was
apparent.


120
differences between the normal and anesthesia conditions
were found in this study, it is suspected that reduced jaw
displacement is the result of pressure alone. However,
further study of speech production under a condition of
pressure alone is necessary. Such an investigation might
also include jaw displacement and movement under conditions
of varying amounts of pressure to ascertain if further
reduction results from further increases in pressure.
Conclusions
This study was designed to evaluate the effects of
anesthesia to the right auriculotemporal nerve and a subse
quent application of a light pressure to the left TMJ
capsule. The affects were assessed on a series of tasks
designed to measure subjects' abilities to discriminate
between jaw positions and weights of capsules held between
the central incisors. The affects of the experimental
procedures were assessed also on subjects' production of
speech elements including diphthongs, vowel-consonant-
vowel sequences, and a sample of connected speech and two
tasks of nonspeech oral movement. This study was undertaken
to define more clearly the role of the sensory mechanism of
the TMJ in monitoring the movement and positioning of the
mandible for these selected tasks.
The results of the present study suggest that uni
lateral anesthetization of the auriculotemporal nerve does
not consistently alter subjects' performance on the tasks


129
Table 24 continued
Elevate Tongue Dorsum
Measure
Condition
Anes thesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis of
Repeated Measures
SS DF MS F
Twelve:
A
2.
,01
1 .
,01
Range of
B
1 .
,01
2.
01
Horizontal
C
0.
,67
2.
,01
Movement
D
3.
,68
4.
.02
from TR
Mean
1 .
.84
2.
.26
to LT
S. D.
0.
.68
0.
.63
Thirteen:
A
8,
.04
9.
,38
Time from
B
12,
.73
11 .
,72
TC to LT
C
18,
.50
15.
74
Position
D
22,
,44
24.
.12
Mean
13.
,90
15.
.24
S.D.
3,
.04
3.
.24
Fourteen:
A
2.
.68
4,
.36
Time from
B
6,
.36
5.
. 36
TC to TR
C
5,
. 36
5 ,
.70
Position
D
11 ,
. 39
16.
.42
Mean
6
.45
8.
.02
S.D.
1 ,
.82
2.
.83
Fifteen:
A
5.
.36
5.
.02
Time from
B
6.
.36
6,
.36
TR to LT
C
7
.04
10,
.05
Position
D
11
.06
7,
.71
Mean
7
.45
7,
.29
S.D.
1
.25
1 .
.07
1.01
1 .01
1.34
3.35
1 168 4.08 2 2.04 0.860
0.56
13.74
13.74
15.08
25.12
16.92 81.34 2 40.67 3.177
2.75
5.36
5.70
6.36
17.76
8.80 50.33 2 25.17 2.638
2.99
8.38
8.04
8.71
7.37
8.12 7.00 2 3.50 0.410
0.29


107
Anesthetization of the Auriculotemporal Nerve
Perceptual Measures
The anesthetization procedure utilized in this study
appeared to have little disruptive influence on subjects'
abilities to discriminate differences in pairs of jaw positions
or to discriminate between the weights of capsule pairs placed
between the teeth. The only observable alteration was a
slight disruption in the ability to discriminate differences
in interdental thicknesses (Table 3) and lateral jaw positions
to the right of midline (Table 7). The mean difference
necessary to discriminate the difference in the thickness of
block pairs was 1.38 mm under the control condition and in
creased to 1.75 mm for anesthesia. A difference limen of
1.12 mm was obtained for discriminating between pairs of jaw
positions fo the right of midline. The difference limen
increased to 1.45 mm under the anesthesia condition.
The results of the task which required subjects to
duplicate an interdental space were not supportive of pre
vious research findings (Thilander, 1961; Ransjo and Thilander,
1963; and Larsson and Thilander, 1964). The subjects in the
present experiment performed similarly under the normal and
anesthesia conditions. That is, the mean range of jaw posi
tions over ten trials attempting to duplicate a standard was
6.00 mm for the normal condition, Table 1. Additionally, the
mean jaw position (for ten trials) from the standard did
not differ noticable between


74
Tab!e 6
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Jaw Position Discrimination to the Left
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm -
0.5
mm
37.5%
87.5%
37.5%
0
mm -
1.0
mm
50
62.5
75
0
mm -
1.5
mm
50
75
75
0
mm -
2.0
mm
75
100
87.5
0
mm -
2.5
mm
87.5
87.5
100
0
mm -
3.0
mm
100
100
100
0
mm -
3.5
mm
100
100
100
0
mm -
4.0
mm
100
100
100
0
mm -
4.5
mm
100
100
100
0
mm -
5.0
mm
100
100
100


138
Table 29
Vowel-Consonant-Vowel /isi/
Summary:
Analysis of
Condi tl on Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Press ure
SS
df
MS
F
One:
A
2.23
2.01
2.23
Vertical
B
0.22
1.34
0.00
Jaw Posi-
C
4.47
2.68
2.90
tion for
Mean
2.31
2.01
1 .71
3.56
2
1 .78
0.859
V1
S.D.
1 23
0.39
0.88
Two:
A
4.69
4.47
5.36
Horizontal
B
4.69
3.80
3.35
Jaw Posi-
C
4.02
2.23
2.68
tion for
Mean
4.47
3.50
3.80
9.85
2
4.93
3.707*
V1
S.D.
0.22
0.66
0.80
Three:
A
-0.67
-1.56
-1.12
Vertical
B
-2.01
-2.01
-1.12
Jaw Posi-
C
0.67
0.45
0.67
tion for
Mean
-0.67
-1.04
-0.52
2.89
2
1 .44
2.364
C
S.D.
0.77
0.76
0.60
Four:
A
2.46
2.46
2.90
Horizontal
B
3.35
3.13
3.13
Jaw Posi-
C
0.89
0.45
0.89
tion for
Mean
2.23
2.01
2.31
0.96
2
0.48
1 .600
C
S.D.
0.72
0.80
0.71
Five:
A
0.67
0.67
1 .79
Vertical
B
0.00
0.67
-0.22
Jaw Posi-
C
3.35
2.01
2.23
tion for
Mean
1 34
1.12
1 .27
0.52
2
0.26
0.160
V2
S.D.
1 .02
0.45
0.75
Six:
A
4.02
4.69
4.91
Horizontal
B
4.24
3.35
3.57
Jaw Posi-
C
2.90
2.01
2.68
tion for
Mean
3.72
3.35
3.72
1 .85
2
0.93
1 .428
V?
S.D.
0.41
0.77
0.65


101
Table 19
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /usa./
Measures Condition Pairs
Normal/
Normal/
Anesthesia-
Anesthesia/
Anes thesia-
Vertical Displacement
Anesthesia
Pressure
Pressure
Initial Vowel /a/
6.48/6.55
6.48/6.63
6.55/6.63
Consonant /s/
-0.96/-0.96
-0.96/-0.52*
-0.96/-0.52
Final Vowel /a/
4.17/3.28
4.17/3.72
3.28/3.72
Horizon tal Displacement
Initial Vowel /a/
5.36/5.21
5.36/5.06
5.21/5.06
Consonant /s/
2.46/2.23
2.46/2.53
2.23/2.53
Final Vowel /a./
5.06/4.47
5.06/4.76
4.47/4.76
Ranqe of Vertical Movement
initial Vowel to Final
Vowel
2.61/3.57
2.61/2.90
3.57/2.90
Initial Vowel to Consonant
7.44/7.52
7.44/7.15
7.52/7.15
Consonant to Final Vowel
5.21/4.40
5.21/4.31*
4.40/4.31
Ranqe of Horizontal Movement
Ini ti a 1 Vowel to Final
Vowel
3.20/3.20
3.20/2.75
3.20/2.75
Initial Vowel to Consonant
3.13/3.06
3.13/2.68
3.06/2.68
Consonant to Final Vowel
2.75/2.53
2.75/2.46
2.53/2.46
Duration of Production
Initial Vowel to Final
Vowel
11.22/10.78
11.22/11.22
10.78/11.22
Initial Vowel to Consonant
4.55/4.44
4.55/5.00
4.44/5.00
Consonant to Final Vowel
6.67/6.33
6.67/6.22
6.33/6.22
p<. 05


139
Table 29 continued
Vowel-Consonant-Vowel /isi/
Summary:
Analysis of
Condition Repeated Measures
Anes thesia/
Measure Subject Normal Anes thes i a Pressure 11. d_f MS £_
Seven:
A
1.56
1.34
0.89
Range of
B
1.12
2.01
0.22
Vertical
C
1.12
0.67
0.67
Movement
Mean
1.27
1 .34
0.59
3.18
2
1 .59
0.621
from Vi
to V2
S.D.
0.15
0.39
0.20
Eight:
A
2.23
1 .34
1 .79
Range of
B
1 34
0.89
0.67
Horizontal
C
3.13
1 .79
2.01
Movement
Mean
2.23
1.34
1 .49
9.18
2
4.59
3.285
from V,
to V2 1
S.D.
0.52
0.26
0.41
Ni ne:
A
2.90
3.57
3.35
Range of
B
2.23
3.35
2.01
Vertical
C
3.80
2.23
2.23
Movement
Mean
2.98
3.05
2.53
2.74
2
1.37
0.515
from V-]
to C
S.D.
0.45
0.41
0.41
Ten:
A
2.23
2.23
2.46
Range of
B
1 .34
0.67
0.45
Horizontal
C
3.13
1.79
2.01
Movement
Mean
2.23
1 .56
1 .64
5.41
2
2.70
2.643
from V-j
to C
S.D.
0.52
0.46
0.61
El even:
A
2.23
3.13
3.13
Range of
B
2.01
2.68
1.12
Vertical
C
2.68
1 .56
2.01
Movement
Mean
2.31
2.46
2.08
1.41
2
0.70
0.493
from C
to V 2
S.D.
0.20
0.46
0.58
Twelve:
A
2.23
2.01
1 .56
Range of
B
1.12
0.67
0.67
Horizontal
C
2.01
1 .56
1.79
Movement
Mean
1 .79
1 .41
1 .34
2.30
2
1.15
1 .984
from C
S.D.
0.34
0.39
0.34
to V2


36
the other oral structures during speech. Hansen (1952)
studied speech intelligibility using single words under
varying conditions of jaw restriction from full restriction
to no restriction. He found no differences in intelligi
bility among any of the conditions. This researcher noted,
however, that a speech sample simulating connected speech
might yield different results. These findings are in agree
ment with those of Kent (1972), who reported the indepen
dence of tongue and jaw dynamics and the apparent compensa
tory action between the two.
Weiss (1969a) disrupted lingual and palatal taction
in eleven year olds and reported that this disruption does
not significantly effect the acoustic parameters of articu
lation. Weiss (1969b) evaluated the lingual-palatal and
mandibular placement of the subjects of his earlier study.
He discovered that the tongue tip placement for some phonetic
productions were disrupted, although there was no signifi
cant overall disruption. However, he did report that there
was greater mandibular displacement after anesthesia for the
phonemes III and two phonemes that seem to involve less
tactile feedback than most. Following anesthetization, there
was also greater variation in the physiologic rest position
of the mandible. Weiss (1969b) questioned whether disrupted
taction of one structure in the articulatory system affects
the function of another in the same system.
Sussman and Smith (1971) monitored and recorded jaw
movements under varying degrees of DAF. They reported no


135
Table 27 continued
Diphthong /all/
Measure
Condition
Anesthesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis
Repeated
SS df
Six:
A
0.
.67
1 .
. 34
1 .
.34
Range of
B
1 .
. 79
1 .
.12
0.
.45
Horizonta 1
C
0.
.67
0.
.67
0.
.89
Movement
D
2.
.46
2,
.23
1 .
.56
Mean
1
.40
1 .
. 34
1 ,
.06
S.D.
0.
.44
0,
. 33
0.
.25
Seven:
A
5
.36
5.
.58
4.
.02
Time from
B
5.
.14
5,
.14
4.
.69
Initial
C
8.
.26
8.
.93
8
.49
to Final
D
5.
.81
6.
.70
5,
. 36
Frame
Mean
6,
.14
6.
.59
5.
.64
S.D.
0.
.72
0.
.85
0.
.99
of
Measures
MS F
.86 0.997
.19 1.516


18
6
1.
Sphenomandibular Ligament
4.
Stylomandibular Ligament
2.
Angular Spine of Sphenoid
5.
Styloid Process
3.
Mandibular Foramen
6.
Angle of Mandible
Figure 7
Sphenomandi bul ar and Stylomandibular Ligaments:
Medial View


131
Table 25 continued
Diphthong /a I/
Measure
Condi ti on
Anesthesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis of
Repeated Measures
SS df MS F
Six:
A
0.67
0.67
Range of
B
1.56
2.68
Horizontal
C
1.12
1.80
Movement
D
1 .56
2.01
Mean
1 .23
1 .79
S.D.
0.21
0.42
Seven:
A
5.80
3.80
Time
B
4.47
3.57
from
C
5.36
4.91
Initial to
D
5.36
4.91
Final Frame
Mean
5.25
4.30
S.D.
0.28
0.36
0.67
2.01
0.67
1 .80
1 .28 5.056 2 2.53 1.690
0.36
4.69
4.24
5.14
5.36
4.86 12.17 2 6.08 4.813*
0.25


56
Planes of Reference
Three lines of reference were constructed on the template
for measurement of the vertical and horizontal positions of
the mandible. Figure 12 illustrates these lines of reference.
Line PP. This line defines the palatal plane which is a
standard reference line in cephalometric studies. This line
is defined as a line which passes through the midpoint of the
anterior nasal spine and the midpoint of the posterior nasal
spine. This line was chosen because it approximates the
horizontal plane and provides a reference line for measuring
the vertical position of the mandible.
Line AB. This line represents a plane which is parallel
to the palatal plane and is tangent to the most inferior point
of the central maxillary incisor. This line also approximates
a horizontal plane and allows for easier measuring of vertical
jaw positions than would making measurements from the central
mandibular incisor to the palatal plane. The vertical posi
tion of the mandible was recorded relative to this line.
Line CD. This line represents a plane which is perpen
dicular to the palatal plane. This line passes through the
most inferior midpoint of the upper central incisor. This line
approximates a vertical plane and serves as the reference for
measuring the horizontal positioning of the mandible.
Definition of Measurements
The vertical and horizontal positions of the mandible
were measured relative to the planes of reference defined


87
a test of the statistical hypothesis (null hyphthesis),
Ho: all test condition means are equal. The alternate
hypothesis, Hj states that at least one pair of condi
tion means differ significantly.
In order to determine between which pair of means
statistical significance exists, the Newman-Keuls Procedure
(Keppel, 1973) was utilized as a second step in the statis
tical analysis. This procedure allows for multiple com
parisons of the test condition means and indicates between
which pairs a statistical significance exists. A summary
of the Newman Keuls analysis, that is, the paired condi
tion values, are presented for each of the ten tasks ana
lyzed statistically, Tables 12 through 21.
The values for vertical and horizontal displacement
and the values for the range of motion are presented in
millimeters. The values for duration of production are
presented in number of frames. At a filming rate of 24
frames per second, the time between each frame is 40 milli
seconds .
Nonspeech Oral Movements
Elevation of tongue tip
The amount of vertical mandibular displacement was
measured at three points during the movement, requiring
each subject to elevate his tongue tip. As listed in
Table 12, these measurements of vertical jaw displacement
were taken when the tongue contacted the alveolar ridge,


29
mediating the perception of position, but also appear to act
as a protective mechanism during extreme open positions of
the mandible.
The evidence to date suggests that a subject's ability
to perceive and/or to discriminate between different mandi
bular positions, as measured by tasks of interdental thickness
discrimination, is independent of the presence of natural
or artificial dentition. In addition, this ability also
appears to be independent of the sensory integrity of the an
tagonistic teeth. However, there is strong evidence that the
nerve endings in the TMJ are responsible, at least in part,
for mediating perception of mandibular position.
More recently, Si i rila and Laine (1972) presented the
results of a study designed to study the effect of anesthesia
of the TMJ capsule on subjects' ability to judge between dif
ferences in mouth opening. These researchers used a modi
fied caliper to establish the difference necessary to descrim-
inate mouth openings from a series of standard openings.
Subjects' performance under bilateral intracapsular TMJ
anesthesia was equivalent to their performance for the normal
condition. They concluded that different sensory mechanisms
might be involved in replicating a mouth opening (Thilander,
1961) and their task of size discrimination. However,
Siirila and Laine's (1972) test protocol allowed subjects
to tap their teeth against the test instrument. Tapping
very likely activated sensory endings in the periodontal
ligament and receptors in the TMJ that respond to movement.


50
from this contact and 2) elevate the dorsum of the tongue up
against the roof of the mouth and drop it from this contact.
Each of these two tasks were performed three times by each
subject.
Speech Sample
A primary purpose of the study was assessment of the
effects of the experimental conditions on mandibular posi
tion during speech production. A speech sample was devel
oped which provided varied amounts of 1ingual-palatal con
tact, required a wide range of mandibular positioning, and
contained a wide range of speech sounds. The speech sample
required each subject to produce a series of diphthongs, a
series of vowel-consonant-vowel (VCV) combinations, as well
as a sample of connected speech.
Vowel-consonant-vowel s : / i s i / fesa/, /iki/, and /a-ka./
The VCV combinations were formed using consonants and
vowels that have been reported to require a wide range of
mandibular placements. Kent and Moll (1972) and Owens (1973)
have shown that front consonants, such as the /s/, and high
vowels, such as /i/, are produced with a more elevated man
dibular placement than are the back consonants, such as /k/
and the low vowels, such as /a/. Therefore, the following
VCV combinations were developed: / i s i / fa. so./, /iki/, and
/aka./. Each of the VCV combinations were spoken three times
by each subject for three of the conditions. Subjects were
instructed to put the same stress on the second vowel as
they did on the first one.


84
amount of required jaw displacement decreased for the conso
nants at the end of "watches" and in "Tee Vee", the jaw began
to close sooner for anesthesia. Jaw displacement for the
/ tf / in "watches" and /1/ in "Tee Vee" appeared equivalent
for the two conditions. As the amount of required jaw dis
placement increased for the open sounds at the end of the
passage, the jaw opened more for the normal condition. This
is interpreted as over-shooting of the target position for
the production of open speech sounds.
On the other hand, pressure appeared to reduce vertical
displacement. It appeared to do so consistently over all the
speech elements in the speech sample, both open and closed.
The pattern of jaw posturing in the horizontal dimen
sion is similar also for the three conditions, Figure 14.
The most anterior jaw postures are observed for the /tj/ in
"watches" and the /t/ in "Tee Vee". The most retruded pos
tures are observed for the /a/ and /n/ in "Connie" and the
// in "watches". These observations, again, are compatible
with previous research findings (Kent and Moll, 1972 and
Owens, 1973). The findings also support observations of the
hinge action of the mandible. That is, the greater the
vertical displacement of the mandible, the more retruded the
structure will be.
The effects of anesthesia and pressure observed in the
vertical dimensions are not readily apparent in the horizontal
plane. The path of jaw movement for any one condition inter
sects the others.


125
Table 23 continued
Elevate Tongue Tip
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
Six:
A
7.
.70
10.
.05
9.
.38
Horizontal
B
5.
,36
5.
,36
3.
.68
Jaw Posi-
C
5.
. 36
4.
.02
5.
. 36
tion at LT
D
8.
,71
8.
.38
6.
, 70
Mean
6.
,78
6.
,95
6.
.28
4
.33
2
2
.17
0.
,860
S.D.
0.
.85
1 ,
.38
1 .
.20
Seven:
A
2.
.68
1 ,
.34
1 .
.01
Range of
B
0.
.00
0,
.34
1 ,
.34
Vertical
C
2.
.68
6,
.03
4.
.02
Movement
D
4.
.69
1 ,
. 34
3.
.02
from TC
Mean
2.
.51
2,
.26
2.
.34
1 1
CO
o
2
5
.54
0
.453
to LT
S.D.
0.
.96
1
.28
0,
.71
Eight:
A
1 .
.01
1 ,
. 34
1 .
.34
Range of
B
0.
.00
0.
.67
1 .
. 34
Horizontal
C
0.
.00
0.
.67
0,
.34
Movement
D
0.
.34
0.
.00
0,
.34
from TC
Mean
0.
, 34
0,
.67
0.
.84
2
.33
2
1
.17
3.
.621
to LT
S.D.
0.
.24
0
.27
0,
.29
Nine:
A
2.
,68
2,
.01
1.
.34
Range of
B
0.
.67
2.
.01
2,
.34
Vertical
C
0.
.67
1
.68
1
.01
Movement
D
0.
.67
0
. 34
1 .
.01
from TC
Mean
1.
.17
1 .
.51
1 .
.42
1
.08
2
0
.54
0
.330
to TR
S.D.
0.
.50
0.
.40
0.
.32
Ten:
A
1.
.34
1,
.01
1
.01
Range of
B
0.
.00
1
.01
1
.01
Horizontal
C
0.
.67
0
.67
1
.01
Movement
D
0,
.34
0
.34
0.
.34
from TC
Mean
0,
.59
0
. 75
0,
.84
0
. 58
2
0
.29
0
.525
to TR
El even:
A
1.
,01
3
.35
1.
.34
Range of
B
1.
.01
2.
.01
1
.01
Vertical
C
2.
. 34
4,
. 36
4
.36
Movement
D
5 .
.36
1 .
.01
3.
.68
from TR
Mean
2.
.43
2
.68
2,
.60
0
. 58
2
0
.29
0
.037
to LT
S.D.
1 .
.03
0
.74
0.
.84


40
of the mandible. All of the tasks were performed under the
two experimental conditions and under a normal, control
condition with no anesthesia and no pressure. The three
categories of tasks included: 1) four perceptual measures
of mandibular position discrimination and one perceptual
measure of interdental weight discrimination, 2) two tasks
requiring nonspeech oral movements, and 3) nine tasks
requiring speech sound production. Thus, there was a total
of sixteen separate tasks.
The specific objectives of the study were:
1) to compare subjects' performance on each of the
five perceptual tasks under the two experimental conditions
and the one control condition,
2) to compare subjects' performance on each of the
two tasks requiring nonspeech oral movements under the two
experimental conditions and one control condition, and
3) to compare subjects' performance on each of the
three tasks requiring speech sound production under the two
experimental condition and one control condition.


TABLE OF CONTENTS
PAGE
ACKNOWLEDGEMENTS ii
LIST OF TABLES v
LIST OF FIGURES viii
ABSTRACT ix
CHAPTER
ONE INTRODUCTION 1
Anatomy and Physiology 2
Review of Literature 19
TWO STATEMENT OF PROBLEM 38
Statement of Purpose 39
Specific Objectives 39
THREE METHODS AND PROCEDURES 41
Subject Selection 41
Experimental Tasks 41
Experimental Procedures 51
Filming Procedures 54
Procedures for Data Collection 55
FOUR RESULTS 65
Analysis of Perceptual Tasks and Connected
Speech 65
Analysis of Speech Tasks and Nonspeech
Oral Movements 86


1
2
3
4
5
6
7
8
9
10
11
LIST OF TABLES
Page
Individual Performance Scores and Group Means,
Ranges, and S.D.s for Duplication of Interdental
Space Task: Range of Jaw Position for Ten Trials...66
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard 68
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination 70
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination 71
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Left 73
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Left 74
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Ri ght ...75
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Right 76
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination 78
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Anterior-Posterior Jaw Positions 79
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination 80
v


12
Temporomandibular Articulation
The TMJ is unique among all the joints of the human
body. It is a gynglmoarthrodial (sliding hinge) joint.
Unlike most articulating surfaces, the TMJ is not covered
by hyaline cartilage, but rather, is covered by an avascu
lar, fibrous protein, collagen. Also unique to the TMJ
articulation is the fact that the two articulating complexes
house teeth, whose shape and position guide the joint when
teeth come to occlusion. Finally, the bilateral articula
tion with the skull restricts certain mandibular motions,
such as lateral movement. The sliding and hinge movement
of the TMJ is possible because of an articular disc or
meniscus interposed between the temporal bone and the con
dylar process of the mandible, thus dividing the articular
space into an upper and a lower compartment. Figure 4
illustrates a sagittal section of the TMJ articulation. The
hinge or rotational movement occurs between the condyle and
articular disc while the sliding or translational movement
occurs between the temporal bone and the meniscus.
The articular disc is a thin oval plate with tight
lateral and medial attachments to the condyle, an elastic
posterior attachment to the tympanic plate of the temporal
bone and an anterior attachment to the articular capsule
and to the lateral pterygoid muscle. The shape of the disc
is such that it accommodates itself with the surface of the
condylar process below and temporal bone above.
The TMJ is surrounded by a thin articular capsule,
which is illustrated in Figure 5. The capsule is loosely


25
investigators have been remarkably similar. Thilander (1961)
described a task which required subjects to choose a random
jaw position between the rest position and maximum jaw open
position and then to replicate that position ten times. Under
normal conditions, the subjects came within plus or minus
1.6 mm of duplicating this position over 20 trials. Ringel
et al ( 1 967) used a modified vernier-type caliper placed
between the biting surfaces of the upper and lower central
incisors. Their results indicated that absolute difference
limen values are relatively independent of the degree of
mouth opening. They reported an average difference limen of
2.04 mm. Williams and LaPointe (1972) and Williams et al.
(1974) used pairs of plastic blocks and pairs of plastic
wedges to attain difference limens. With the use of pairs
of plastic blocks, they reported an average difference limen
of 1.91 mm. They concluded also that interdental thickness
discrimination was independent of mouth opening. Williams
et al, (1974) used pairs of plastic wedges (the wedges
required quided mandibular motion to a given position), to
establish difference limens and reported an average difference
limen of 1.37 mm. They suggested that the lower difference
limen, using the wedges, reflected the mandibular movement
required by the instrumentation and provided subsequent
activation of additional sensory receptors in the TMJ.
Further understanding of the sensory mechanism of
mandibular kinesthesia has been gained from other studies
of interdental thickness discrimination. Originally, the


xml version 1.0 encoding UTF-8
REPORT xmlns http:www.fcla.edudlsmddaitss xmlns:xsi http:www.w3.org2001XMLSchema-instance xsi:schemaLocation http:www.fcla.edudlsmddaitssdaitssReport.xsd
INGEST IEID EKP2RBVIV_J3QFRT INGEST_TIME 2012-12-07T22:33:29Z PACKAGE AA00012901_00001
AGREEMENT_INFO ACCOUNT UF PROJECT UFDC
FILES


33
as resulting from malocclusion, the malocclusion was adjusted
with an appliance. The resulting masticatory movement was
found to be much smoother.
In a study reported by Schaerer et al. (1 966), anesthesia
of the TMJ capsules and periodontal ligament did not effect
mandibular movements, muscle activity, or contact between teeth
during chewing. Thus, it appears that mandibular movement and
positioning during the processes of deglutition and mastication
in normal individuals is not disrupted by anesthetizing the
TMJ. However, abnormal masticatory patterns have been observed
in individuals who have demonstrated excessive occlusal wear
and have had pain, clicking, or other symtoms of TMJ dysfunc
tion. This might suggest that long standing disruption of
TMJ function is necessary before there is observable altera
tion in the masticatory stroke.
Speech function
The initial interest in mandibular movement and position
during speech appears to have been generated by researchers in
the field of prosthetic dentistry. Simple phonetic tests, such
as counting from one to ten or repeating /s/ loaded words,
hve been used to establish "closest speaking space" or closest
interdental space in the construction of clinically accepted
dentures (Geissler, 1971 and Gillings, 1973).
Recently, speech researchers have begun to measure
mandibular position for speech function while systematically
varying phonetic context. The results of the research from


3
Sicher and DuBrul (1970), and Zemlin (1968).
Handi ble: Origin and Growth
The body of the mandible is horseshoe shaped and ex
tends upward and backward on both sides into the mandibular
ramus. The ramus extends upwards from the mandibular angle
and ends in two processes, the anterior, muscular coronoid
process and the posterior, articular condylar process. The
mandible is formed embryologically from the first branchial
arch, which is known also as the mandibular arch. The first
arch ultimately gives rise to the lower lip, the muscles of
mastication, the mandible, the anterior portion of the tongue,
and some of the middle ear structures. The mandibular arch
is joined with the maxillary processes at the extreme lateral
and rostral margins. The progressive anterior fusion between
these two processes reduces the width of the primative oral
fissure and forms the cheeks. At birth, the mandible is di
vided into halves. It contains the alveoli for the deciduous
dentition. The angle of the ramus with the mandibular plane
is obtuse, about 170 Shortly after birth, the two halves
of the mandible become fused at the symphysis, beginning from
below. Fusion is usually complete by the first year. With
growth, the angle of the mandible becomes less and less obtuse.
At four years of age, it is about 140 and in the adult man
dible, the angle is about 110 -120 .
The growing mandible enlarges in a forward and downward
manner with respect to the cranial base. However, the actual
course of growth proceeds in a complex process of bone


137
Table 28 continued
Diphthong /ol/
Summary:
Analysis of
Condi ti on Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure
SS
df
MS
F
Six:
A
0.
.89
0,
.89
1 .
.34
Range of
B
2.
.01
0.
.67
0.
.89
Horizontal
C
1 .
.34
1
.12
0.
.89
Movement
D
0.
.89
1 .
.12
1 .
.12
Mean
1
.28
0
.95
1 .
.06
1 56
2
0.78
0.
.91 3
S.D.
0.
.26
0,
.10
0.
.10
Seven:
A
4.
.69
4.
.24
3,
.57
Time from
B
4.
.24
3.
.80
4.
.02
Initial
C
5.
.14
5,
.14
4.
.24
to Final
D
4.
.24
4
.02
4.
.02
Frame
Mean
4
.58
4
.30
3,
.96
5.06
2
2.53
2
.588
S.D.
0.
. 21
0
.29
0.
.14


119
of the mandible and the reduced range of mandibular motion
might have been compensatory to the presence of TMJ pain.
The data would suggest that pain becomes more noticable with
increased mandibular displacement.
The lack of improvement reported by Larsson and Thilan-
der (1964) for bilateral anesthesia may reflect the fact that
pressure was applied to a successfully anesthetized joint.
Thus, the sensation of pressure or pain was not available
to restrict jaw movement.
The results reported by Ransjo and Thilander (1963)
might be interpreted similarly. In that study, subjects with
unilateral joint dysfunction, due to malocclusion, found it
difficult to replicate an arbitrary jaw position. This abi
lity was not normalized when a light pressure was applied to
the side of dysfunction. However, when pressure was applied
to the normal side, the range of jaw positions for the ten
trials was significantly reduced. Again, these findings can
be interpreted as indicating a reduced sensation of the pres
sure of the effected side. Whereas, the sensation of pressure,
or pain, available to the normal side, restricted movement of
the condyle.
The fact cannot be overlooked that reduced jaw dis
placement may be the result of the cumulative effects of anes
thesia and pressure. Other researchers (McCroskey, 1958 and
Ringel and Steer, 1963) have reported that sensory disturb
ances of the oral structures are cumulative in their effect
on speech output. Since so few significant


91
Table 13
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Tongue Dorsum Elevation
Measures Condition Pairs
Vertical Displacement
Normal/
Anes thes i a
Normal/
Anesthesia-
Pressure
Anesthesia/
Anesthesia-
Pressure
Tongue Contact
7.91/6.28
7.91/7.37
6.28/7.37
Tongue Release
8.38/7.44
8.38/8.04
7.44/8.04
Lowest Tongue
10.25/8.78
10.25/8.58
8.78/8.58
Horizontal Displacement
Tongue Contact
8.38/7.24
8.38/7.44
7.24/7.44
Tongue Release
8.98/8.11
8.98/7.77
8.11/7.77
Lowest Tongue
7.44/7.04
7.44/6.62
7.04/6.62
Ranqe of Vertical Movement
Tongue Contact to Lowest
Tongue
2.34/2.68
2.34/1.51
2.68/1 .51
Tongue Contact to Tongue
Release
0.92/2.26
0.92/1.76
2.26/1.76
Tongue Release to Lowest
Tongue
2.60/2.85
2.60/2.77
2.85/2.77
Ranqe of Horizontal Movement
Tongue Contact to Lowest
Tongue
2.10/2.34
2.10/1.84
2.34/1.84
Tongue Contact to Tongue
Release
1.17/1.93
1.17/1.09
1 .93/1.09
Tongue Release to Lowest
Tongue
1.84/2.26
2.84/1.68
2.26/1.68
Duration of Production
Tongue Contact to Lowest
Tongue
20.75/22.75
20.75/25.25
22.75/25.25
Tongue Contact to Tongue
Release
9.63/11.98
9.63/13.13
11.98/13.13
Tongue Release to Lowest
Tongue 11.13/10.88 11.13/12.13 10.88/12.13
p.05


156
Woodford, L. D., Oral Stereognosis. Master's Thesis,
University of Illinois (1964).
Zemlin, W.R., SPEECH AND HEARING SCIENCE, Englewood Cliffs,
New Jersey: Prentice-Hall (1968).


109
Finally, a task of interdental weight discrimination
was included in the test battery in order to determine the
role of the sensory mechanism of the TMJ in weight discrim
ination. The mean difference required in two weights before
subjects could detect a difference was 7.75 gms for the nor
mal condition and 7.12 gms for the anesthesia condition.
These data suggest that the sensory mechanism of the TMJ
does not have a role in monitoring load on the mandible,
at least in the weight range studied, that is 5 25 gms.
Sentence
For this sample of connected speech, anesthesia ap
peared to increase vertical jaw displacement rather consist
ently for open sound elements, Figure 13. Vertical dis
placement was greater for the anesthesia condition than
for normal or pressure conditions throughout the production
of the open sounds in the first half of the speech sample.
There appeared to be no influence of anesthesia on the
posturing of the mandible in the horizontal dimension for this
connected speech sample. Figure 14 illustrates that the
pattern of jaw movement for each of the three conditions
overlaps each of the other conditions. Moreover, a distinct
pattern is not discernable for any specific condition.
It appears that the anesthesia altered vertical pos
turing of the jaw differentially. During the production of
open sounds, anesthesia caused the jaw to maintain a greater
amount of displacement. However, for the closed sounds,
subjects' jaw posturing for the anesthesia condition approx
imated the posture observed for the normal condition. This


6
superior borders of the body. The mental vessels and nerve
exit at the foramen. The oblique line is the faint ridge,
which proceeds posteriorly and superiorly from the mental
foramen becoming continuous with the anterior border of the
ramus. It provides attachments for the quadratus labii
inferior and triangularis; the platysma attaches just infer
ior to the oblique line. The superior surface of the man
dibular body is the tooth-bearing alveolar process. It is
hollowed into numerous cavities (alveoli) for the reception
of teeth. The alveolar process resorbs with tooth loss re
sulting in a reduced vertical dimension of the mandible.
The ramus of the mandible is directed superiorly from
the posterior portion of the body of the mandible. The ramus
divides superiorly into the condylar and the coronoid pro
cesses. These processes are separated by the mandibular or
the semilunar notch. The anterior, coronoid process serves
as the point of attachment for the temporalis muscle. The
condyloid process frames the mandibular head, which articu
lates with the mandibular fossa of the temporal bone by way
of the TMJ. The lateral surface of the ramus gives attach
ment to the masseter muscle throughout nearly its whole ex
tent.
The medial aspect of the mandible is illustrated in
Figure 2. Two small posteriorly directed spines are pro
jected near the symphysis. These ridges or mental spines
are placed one above the other and serve as the origin for
the genioglossus muscle. The geniohyoid muscle originates
just inferior to the mental spines. Inferior and lateral to
the mental spines are the attachments for the anterior belly


118
Table 22
The Amount of Jaw Opening (in mm)
for the Initiation of Each of Ten Tasks
Under the Normal and the Pressure Conditions
Task
Condition
Nonspeech
Tongue Tip Elevation
Tongue Dorsum Elevation
Normal/Pressure
10.45/7.97*
7.91/7.37
Diphthong Production
/ a 1/
/el/
/aU/
loll
11 .22/8.44*
10.72/8.82*
12.84/9.33*
8.54/7.37
Vowel Consonant-Vowel Production
/ i s i /
/a-sa-/
/ i k i /
1 aka. 1
2.30/1.71
6.48/6.83
3.50/3.42
7.67/7.59
p<..05


31
The working condyle, on the side with the food, reached the
maximum opening first. The mandible stopped movement during
chewing for a brief time at its closed stage. Condylar move
ment was prominent in masticatory function, but not for speech.
Finally, the average maximum velocities for chewing were
considerably greater than for speech (6.05 in./sec. and 1.65
in./sec. respectively). Gibbs and Messerman ( 1 972) concluded
that much important information concerning mandibular movement
for speech could be obtained from measuring the vertical and
horizontal motion exclusively.
Interest in mandibular movement for deglutition and the
masticatory process necessarily implies interest in the systems
neurocontrol mechanism. Ingervall et al. (1971) examined the
occlusal positions of the mandible and the movements of the
hyoid bone with and without anesthesia of the TMJ capsules.
These researchers reported that dental contact was common
during swallowing and could find no differences in positions
between swallowing prior to or during anesthetization. The
hyoid bone movement patterns were also independent of the
anesthesia condition.
Ingervall et al. (1972) utilized the films collected
earlier (Ingervall et al ., 1971) and evaluated the influence
of the receptors in the TMJ capsules on the duration of
swallowing and movements of the hyoid bone. They reported
that bilateral anesthetization of the TMJ capsule had no effect
on the duration of the movement of the hyoid bone. This is not


30
Williams and LaPointe (1974), reported earlier, suggested that
smaller values of mouth opening may be discriminated when TMJ
movement is allowed.
Deglutition mastication
The process of deglutition and mastication have been
described narratively by Fletcher (1970 and 1971). Fletcher
(1970) described the role of the mandible in a mature
swallow as providing a stable base from which the oral
strutures function as they collect a bolus and force it
posteriorly. A graphic description of mandibular movement
during mastication has been provided recently by Gibbs et al.
(1971) and Gibbs and Messerman (1972). Using the Case Gnathic
Replicator (Gibbs et al ., 1 966), they were able to record
graphically mandibular motion in three planes of movement.
Many of their comparisons of the mandibular masticatory
process were relative to mandibular movement for speech
function. For example, they found that the maximum vertical
opening for chewing was typically two to four times more than
the vertical opening for speech. The amount of vertical
opening during speech was relatively equal between subjects
while it varied considerably for chewing. Speech function
involved little lateral motion of the mandible whereas there
was a great deal of lateral movement during chewing. Hori
zontal or anterior-posterior movement of the mandible appeared
equal for both processes, however, it was proportionately
greater in relationship to vertical movement for speech. There
was asymetrical motion of the condyles during mastication.


37
overall disruptive effects of DAF on jaw positioning nor on
the duration of the velocity of jaw movement. However, they
did find isolated instances of disruption. Although not
statistically significant, there seemed to be a trend for the
jaw to overshoot its position for some vowels under the 0.3
second delay condition. They also reported a significant in
crease in the length of jaw activity for the 0.1 second delay
condition. These results offer some evidence that auditory
feedback may be important in controlling mandibular position.
Research on mandibular function for speech processes
has demonstrated the vertical and horizontal positioning is
dependent on the phonemic makeup of the speech sample.
Current research has provided information of the independent,
yet complimentary actions of the mandible and the tongue
during articulation. Investigators who have disrupted lingual
tactile and auditory feedback during speech have reported only
minimal and inconsistent alterations of mandibular position.


19
four types of nerve endings in the capsule. Free nerve
endings were the most abundant. Organized endings such as
Ruffini endings, Golgi tendon organs, and the Vater-Pacini
corpuscles are represented, but only sparsely.
Investigations of the role of joint receptors in
perception of position sense and kinesthesis by Mountcastle
and Powell (1959) provide further information of the sensory
capabilities of the TMJ joint receptors. They indentified
two types of slowly adapting nerve endings. These endings
discharged at a steady rate that was influenced only by the
angle of the joint. Individual receptors responded to arcs
of 15 to 20 degrees. Thus, they functioned as absolute
detectors of joint angle. The two groups of endings were
the spray type Ruffini endings and the Golgi tendon organs,
both of which are present in the TMJ.
The blood supply to the TMJ capsule is through the
superficial temporal and maxillary arteries posteriorly and
from the twigs of the masseteric artery anteriorly. The
articular disc, which is avascular in its center, has an
unusually rich plexus of veins on the periphery. The plexus
serves to equalize pressure in the tissues by filling and
emptying as the condyle rocks rythmically forward and back
ward in chewing.
Review of Literature
The purpose of this review is to present the current
understanding of oral sensation and perception with specific
reference to mandibular kinesthesia. In addition, mandibular


9
focus of this discussion will be the two primary muscle
groups. The mandibular musculature can be divided by func
tion or by muscles groups. For the purpose of this discus
sion the musculature will be considered in muscle groups.
The direction of mandibular movement by each of the muscles
is illustrated in Figure 3.
Muscles of Mastication
Mas seter. This muscle originates along the zygomatic
arch and zygomatic process and inserts along the ramus, the
coronoid process and the angle of the mandible. It is in
nervated by the mandibular branch of the Trigeminal nerve and
serves to elevate the mandible.
Temporalis. This muscle has its origin on the floor of
the temporal fossa and the temporal facia. It inserts along
the anterior border of the coronoid process and the anterior
border of the ramus of the mandible. It is also innervated
by the mandibular branch of the Trigeminal nerve. It func
tions to elevate and retract the mandible.
External Pterygoid (Lateral). This muscle originates
from the greater wing of the sphenoid and the lateral sur
face of the lateral pterygoid plate. It inserts on the
anterior portion of the neck of the condylar process and the
meniscus of the mandibular joint. It is innervated by the
mandibular branch of Trigeminal nerve and serves to protrude
the mandible and pull the articular disc anteriorly. It
also assists in the rotary movement of the mandible for
chewing.


99
Table 18
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /isi/
Measures
Normal/ Anesthesia/
Verti cal Di s pi a cement
Normal
Anesthesia
Anesthesia-
Pres sure
Anesthesia-
Pressure
Initial Vowel /i/
Consonant /s/
Final Vowel /i/
2.30/2.01
-0.67/-1.04
1.34/1.11
2.30/1.71
-0.67/-0.52
1.34/1.27
2.01/1.71
-1.04/-0.52
1.11/1.27
Horizontal Displacement
Initial Vowel /i/
Consonant /s/
Final Vowel /i/
4.46/3.50*
2.23/2.01
3.71/3.35
4.46/3.79
2.23/2.30
3.71/3.71
3.50/3.79
2.01/2.30
3.35/3.71
Ranqe of Vertical Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
1.27/2.34
2.97/3.05
2.30/2.46
1.27/0.60
2.97/2.53
2.30/2.08
1 .34/0.60
3.05/2.53
2.46/2.08
Ranqe of Horizontal Movement
Inita1 Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
2.23/1.34
2.23/1.56
1.78/1.41
2.23/1.49
2.23/1.64
1.78/1.34
1.34/1 .49
1.56/1.64
1.41/1.34
Duration of Production
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
12.10/11.57
4.00/3.99
8.55/7.56
12.10/10.80*11.57/10.80
4.00/4.78 3.99/4.78
8.55/6.00 7.56/6.00
p .05


6
Phoneme
1
a
1
1
V
1
9
k
1
ay
n
1
w
1
CL,
1
t
1
1
V
<
1
e
1
m

I N T
H E
E V 1
N I
N G
C 0 N
N I
E W
A T
H E
S T
lm
|m
V E
WITH
M E
Normal
Mean
4.52
4.52
3.35
4.36
4.02
4.02
4.02
4.19
4.36
3.02
1 .84
2.68
3.02
3.35
3.86
3.68
4.36
Range
3.35
3.35
3.35
2.68
2.68
4.69
4.02
2.01
4.02
4.69
2.01
2.68
2.68
2.68
2.68
2.68
2.01
Std.Dev
1.76
1.76
1 .64
1 .28
1.22
1 .97
1.81
0.84
1.73
2.08
1 .00
1 .22
1 .59
1 .22
1.14
1 .28
1.16
Mean
4.19
3.68
3.18
4.19
4.36
5.19
5.02
4.19
4.69
3.02
2.34
2.84
3.02
3.35
4.36
4.36
4.86
Range
3.35
2.68
2.68
2.01
2.01
3.35
3.35
2.68
3.35
4.02
2.68
3.35
4.02
3.35
2.01
2.68
2.35
Std.Dev.
1.48
1.16
1 .38
0.84
0.86
1.38
1 .39
1.14
1 .64
1 .59
1.16
1.48
1.77
1 .44
1.16
1 .28
1 .48
Anesthetized anc
Pres
sure
A -*
Mean
5786
4.69
4.02
4.19
4.36
5.02
4.69
3.52
4.19
2.18
2.01
3.52
3.02
4.02
4.02
3.86
4.86
Range
3.35
3. 35
2.68
4.69
4.02
3.35
4.02
4.02
4.02
4.02
4.02
3.35
3.68
4.02
2.68
3.35
2.68
Std.Dev
1.48
1.85
1 .22
2.21
2.08
1.59
1.81
1 .76
1.76
1.77
1.73
1 .38
1 .28
1 .73
1.09
1.38
1.14
03
CJ1
Figure 14
Means, Ranges and S.D.'s of Horizontal Jaw Positions Under Three
Conditions for 17 Sounds Selected From a Connected Speech Sample (N4)


72
midline. (Table 5: X = 1.69 mm and X = 1.62 mm, respectively)
Subjects, as a group, found it easier to discriminate between
positions to the left of midline under the pressure condition
(X = 1.25 mm).
The mean percent of correct subject responses per
stimulus pairs for jaw positions to the left of midline are
presented in Table 6. These data illustrate that subject
performance reached 100% for the normal and anesthesia con
ditions when the difference between the pair of positions
reached 2.5 mm. Only 2.0 mm difference was necessary for
100% performance under the pressure condition. Moreover, the
group means presented in Table 5 and the mean percent of cor
rect subject responses presented in Table 6 fo.r discrimina
tion of jaw positions to the left of midline suggest that
anesthesia had no effect on the subject's discriminative
abilities while pressure to the TMJ, contralateral to the
anesthesia, enhanced performance somewhat. It should be
noted that pressure was always applied to left TMJ capsule,
or, for this task, to the side of jaw movement.
Subject performance scores, group means, and S.D.'s
are presented in Table 7 for the task of discrimination be
tween pairs of lateral jaw positions to the right of midline.
The group means presented in Table 7 suggest that this group
of subjects performed most accurately under the normal
condition (X = 1.12 mm) and performed least accurately under
the pressure condition (X = 2.06 mm). The group mean for the
anesthesia condition (X = 1.45 mm) fell between the two other


79
Table 10
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Anterior-Posterior Jaw Positions
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm -
0.
.5
mm
87.
.5%
75%
75%
0
mm -
1.
.0
mm
100
100
100
0
mm -
1.
.5
mm
75
100
100
0
mm -
2,
.0
mm
87.
,5
100
100
0
mm -
2,
.5
mm
100
100
100
0
mm -
3,
.0
mm
100
100
100


I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Philosophy.
Edward C. Hutchinson, Chairman
Associate Professor of Speech
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Philosophy.
William N. Williams, Cochairman
Associate Professor of Speech
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Pin 1 osophy.
Leonard L. LaPointe
Assistant Professor of Speech


69
anesthesia compared to normal and the performance of A and D
was improved by pressure compared to anesthesia. Only subject
A fit the profile of performance presented by Thilander of
impaired performance under anesthesia condition and improved
under the pressure condition.
Interdental thickness discrimination
Individual subject performance scores for each of the
two runs are presented for the task of interdental thickness
discrimination in Table 3. The mean amount of thickness re
quired for two consecutive correct descriminations is greater
for anesthesia condition (1.75 mm) than for the normal con
dition (1.38 mm). Subjects required an average of 1.50 mm
difference under the pressure condition. This suggests that
some mild disruption occurred due to the anesthesia and some
recovery of discriminative abilities occurred with the ap
plication of pressure. Further analysis (Table 4) revealed
that 100% correct discrimination occurred under the normal
condition and pressure condition when the difference in
block size was 2 mm. However, 4 mm were required under the
anesthesia condition in order to obtain 100 % discrimination.
Discrimination of lateral mandibular position
Each subject's ability to discriminate between pairs of
lateral positions of the mandible was assessed to the left of
and to the right of midline. No difference in subjects' per
formance was observed between the control and anesthesia con
dition when ability on this task was tested to the left of


96
Table 16
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /all/
Measures Condition Pairs
Vertical Displacement
Norma 1/
Anes thesia
Norma 1/
Anesthesia-
Pressure
Anesthesia/
Anesthesia-
Pressure
Initial
12.84/12.34
12.84/9.33*
12.34/9.33*
Final
6.31/5.14
6.31/4.58*
5.14/4.58
Horizontal Displacement
Initial
6.14/5.86
6.14/5.81
5.86/5.81
Final
4.91/4.64
4.91/4.91
4.64/4.91
Ranqe of Vertical Movement
6.59/7.37
6.59/4.80*
7.37/4.80
Ranqe of Horizontal Movement
1.40/1.34
1.40/1.06
1 .34/1.06
Duration of Production
9.17/9.83
9.17/8.42
9.83/8.42
p<. 05


Further, these data suggested that pressure to the TMJ, on
the order of one to two pounds per square inch, inhibits the
translatory motion of the condyle process.
x 1


114
mastication. Ricketts [1964) pointed out that the muscles
that control the action of the TMJ have a high innervation
ratio, with a high degree of sensitivity. Further, Kawamura
(1961) suggested that the temporal muscle may be the most
important muscle in regulating the position of the mandible.
Effect of Pressure
Since there was little disruption of mandibular
posturing caused by the anesthetization procedure in this
study, the restorative powers of pressure to the contralateral
joint (Larsson and Thilander, 1964) could not be adequately
assessed. However, pressure had its own observed effects.
Perceptual Measures
Pressure to the left TMJ capsule, subsequent to anes
thetization of the right auriculotemporal nerve was observed
to reduce the mean range of jaw position for the task of
duplicating an interdental space, Table 1. This might be
interpreted as enhancing the subjects' performance on this
task. Subjects also required less difference in block
thickness to judge differences, Table 3. Since it was ob
served that anesthesia appeared to impair subjects' ability,
the effect of pressure might be interpreted as restorative.
Subjects also found it easier to discriminate between jaw
positions to the left of midi i ri e when pressure was applied,
Table 5.
The most interesting effect of pressure on subject
performance for the perceptual measures was the impairment


55
it at centimeter intervals, was inserted in the subject's
mouth at the initiation of filming. It was, therefore, pos
sible to project the filmed image at some known magnification
relative to life size.
Procedures For Film Data Collection
Measuring Apparatus
A Lafayette Analyzer 16 mm Projector was used to analyze
the cinefluorographic films. The Lafayette Projector is cap
able of frame bv frame projection or continuous projection at
variable speeds. The image of the subject and the ruler was
projected one and one half times larger than life size by ad
justing the position of the perpendicularly mounted tracing
board relative to the projector. It was necessary to project
the image- to this size because of the limitation of the pro
jector to focus the image any smaller. All of the measure
ments were corrected to life size following compilation of
the data.
Construction of Template
Prior to measurement, a template was constructed from
the projected image of the initial frame depicting the mid
line structures. The midline structures included the hard
palate from the anterior nasal spine to the posterior nasal
spine, the upper central incisors, and the alveolar ridge.
These structures were used for constucting lines of reference
as well as for adjusting the template to the frame to be mea
sured in order to insure accuracy of measurement.


Abstract of Dissertation Presented to the Graduate Council of
the University of Florida
in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy
THE ROLE OF THE
TEMPOROMANDIBULAR JOINT
IN MEDIATING PERCEPTION
.OF MANDIBULAR POSITION
by
John Edward Riski
August, 1976
Chairman: Edward C. Hutchinson
Cochairman: William N. Williams
Major Department: Speech
Measures of mandibular positioning and movement are
described for a series of selected speech and nonspeech tasks
under normal and experimental conditions. The purpose of the
study was to evaluate the role of the sensory mechanism of the
temporomandibu 1ar joint in mediating perception of mandibular
position by 1) measurement of the positioning of the mandible
during selected speech and nonspeech tasks following unilateral
auriculotemporal nerve block and 2) measurement of the position
ing of the mandible during selected speech and nonspeech tasks
during the application of a light pressure to the contralateral
temporomandibular joint capsule.


52
and 2) anesthetization of the right auriculotemporal nerve
with a painless pressure administered to the contralateral
TMJ capsule. All of the experimental tasks outlined were
performed by each subject under each of the experimental
conditions and under a normal condition where the subject
received neither anesthesia nor pressure stimulus.
Anesthetization
Anesthetization of the auriculotemporal nerve was
performed and observed by Parker E. Mahan, D.D.S., College
of Dentistry, University of Florida. A 2% xylocaine solution,
with a vaso-constrictor, was injected into the nerve as it
ascends near the posterior border of the mandible. Approx
imately 0.8 cc of xylocaine was used for each anesthetization.
The anesthetized state was maintained for approximately
three to four hours as evidenced by subject report. All
subjects received the anesthesia on their right side.
Pressure
The second experimental condition involved applying
pressure to the left TMJ capsule while the right TMJ was
anesthetized. The pressure device, ill ustra ted in Figure 11,
incorporates a calibrated, spring-loaded disc 2.5 cm in
diameter. The design allows for monitoring the amount of
force that the disc exerts against the TMJ capsule. The
amount of pressure, acknowledged as less than painful
by each subject, varied from 1.0 to 2.0 pounds. The mean


Four young adult males, with normal occlusion and no
history of temporomandibular joint dysfunction, served as sub
jects. Each subject completed all of the tasks under a nor
mal condition, anesthetization of the right auriculotemporal
nerve, and anesthesia with a light pressure (one to two
pounds per square inch) applied to the left temporomandibular
joint capsule.
Each subject completed tasks designed to test his abil
ity to perceive the position of his mandible in the superior-
inferior, 1 atera1-medial, and anterior-posterior dimensions and
discriminate differences in weights of capsules held between
the teeth. In addition, each performed a series of tasks re
quiring speech sound production and tongue elevation. The
anesthetization procedure utilized in this study did not appear
to disrupt subjects' perception of mandibular position for
any of the tasks in or significantly alter the positioning
of the mandible for the speech sample used. However, the
application of pressure disrupted subjects' ability to dis
criminate between pairs of jaw positions to the right of
midline. Further, the application of pressure significantly
reduced the amount of jaw opening when the jaw opening was
observed to be greater than ten millimeters for the normal
condition.
The results of this study were interpreted to suggest
that the sensory mechanism of the temporomandibular joint, at
least the auriculotemporal nerve, has a minimal role in re
gulating the positioning and movement of the mandible.
x


7
1 .
2.
Mental Spines 3.
Mylohyoid Line 4.
5. Angle of Mandible
Mandibular Foramen
Mylohyoid Groove
Figure 2
Mandible: Left Medial Aspect


86
Analysis of Speech Tasks and Monspeech Oral Movements
The measurements of jaw position obtained from the pro
jected cinef1uorographic frames (as outlined in Chapter Two)
have been summarized relative to five parameters of mandibu
lar activity for the ten tasks. These parameters are: verti
cal jaw displacement, horizontal jaw displacement, range of
vertical jaw movement, range of horizontal jaw movement, and
duration or length of production. For each of these five
parameters, measurements were recorded to represent mandibu
lar activity throughout each task. These data were then sub
jected to descriptive analysis, that is, mean and standard
deviation and to a test of statistical significance based
upon the analysis of a repeated measures design. The results
of the descriptive analysis and a summary of the analysis of
repeated measures with the mean square, sum of squares, de
grees of freedom, and F statistic are presented in the ap
pendix. An F value was considered significant when p<.05.
In the repeated measures design, each subject is ob
served under each of the test conditions. This study repre
sents a single factor repeated measures design where there
are three levels to the factor. Those levels are three test
conditions, that is, control, anesthesia, and anesthesia-
pressure.
The analysis of repeated measures provides an analysis
of variance in that the mean score for each condition is
compared with every other mean score. The analysis provides


8
Phoneme
i
i
V
n
NJ I
k
cu
n
w
cu
if
t
1
V
1
e
m
Normal
1 N 1
E
£ I
N_G
£ £
M I
E W
A T
H e
S T
E E
v L_
: w
T H
M £
Mean
3.35
5.19
3.35
3.52
3.52
7.37
5.53
5.70
7.70
0.84
-.34
2.18
1.67
3.02
3.52
3.35
Range
4.69
5.36
5.36
6.03
5.36
9.38
8.04
8.71
8.04
2.68
3.35
4.02
3.35
4.69
5.36
4.69
Std.Dev. 2.12
Anesthetized
2.34
2.44
2.75
2.58
4.17
3.92
4.11
3.52
1.38
1 .39
1 .84
1.59
1.93
2.64
2.12
Mean
3.52
5.02
3.52
4.52
4.36
8.21
6.70
5.19
6.36
0.34
-.34
3.68
2.85
3.68
4.52
4.19
Range
6.03
4.69
3.35
6.70
5.36
8.04
4.02
7.37
8.71
3.35
4.02
3.35
3.35
4.69
4.02
3.35
Std.Dev. 2.59
Anesthetized an
2.08
Pre
1 .76
ss ure
2.81
2.28
3.64
2.12
3.34
3.89
1.59
1.77
1.59
1.58
1.93
2.14
1 .76
Mean
2.85
4.36
2.85
2.85
3.68
6.03
4.52
3.68
4.69
-.84
-1 .00
1 .68
1.34
1 .84
2.85
2.34
Range
5.36
5.36
4.69
4.02
4.69
4.02
2.60
4.02
5.36
3.35
4.69
4.02
2.68
4.69
3.35
4.02
Std.Dev
2.34
2.47
2.28
1 .84
1.93
1.97
1 .38
1.77
2.25
1 .58
2.08
2.01
1.54
2.27
1.70
2.01
1
3.52
6.70
2.90
3.18
2.68
1.41
3.18
4.69
2.21
Figure 13
Means, Ranges and S.D.'s of Vertical Jaw Positions Under Three
Conditions for 17 Sounds Selected From a Connected Apeech Sample (N4)


27
assessing mandibular kinesthesia which required subjects to
choose an arbitrary jaw position between mandibular rest
position and maximum opened jaw position and then attempt
to replicate that position ten times in close succession.
From the results of a series of experiments, including uni
lateral and bilateral anesthetization of the TMJ capsules
and anesthetization of the inferior nerve, she concluded
that the TMJ capsule is responsible at least in part, for
mediating perception of mandibular position. More speci
fically, subject performance varied from normal only under
conditions of unilateral and bilateral anesthetization of the
TMJ capsule. Subject performance was disrupted equally under
unilateral and bilateral anesthetization.
The findings of Larsson and Thilander (1964) prove
quite provocative. These researchers evaluated the effects
of certain "distracting" stimuli including stroboscopic light
flicker, sound stimulis (clicks), stimulation of the right
median nerve, painful pressure applied on the joint, and pain
ful pressure applied anterior to the joint on subjects' abi
lity to replicate arbitrary jaw position (Thilander, 1961).
The subjects performed significantly poorer than normal un
der all conditions of "distracting" stimuli except when
painful pressure was applied to the joint. Performance under
this condition did not vary from normal. Further investiga
tion of this phenomena revealed that a more moderate, pain
less pressure could normalize the disruptive effects of any
of the "distracting" stimuli and even more remarkably, a


Figure 11
Cephalostat and Pressure Device


THE ROLE OF THE
TEMPOROMANDIBULAR JOINT
IN MEDIATING PERCEPTION
OF MANDIBULAR POSITION
by
JOHN EDWARD RISKI
A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF
THE UNIVERSITY OF FLORIDA
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1976


78
Table 9
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination
Condi tion
Subject
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
1 .5 mm
0.5 mm
0.5 mm
2)
2.5
0.5
0.5
B
1)
0.5
0.5
0.5
2)
0.5
0.5
1.0
C
1)
0.5
0.5
0.5
2)
0.5
1 .0
1 .0
D
1)
0.5
1 .0
1 .0
2)
2.0
LO
o
0.5
Means
1.06 mm
0.62 mm
0.68 mm
Standard
Deviation
0.82
0.94
0.23


70
Table 3
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination
Condition
Sub.iect
Trial
Norma 1
Anesthetized
Anesthetized and Pressure
A
1)
1.0 mm
2.0 mm
1 .0 mm
2)
1.0
1 .0
1.0
B
1)
1 .0
1 .0
1.0
2)
2.0
1.0
1 .0
C
1)
2.0
1.0
2.0
2)
1.0
2.0
2.0
D
1)
1 .0
2.0
2.0
2)
2.0
4.0
2.0
Means
1.38 mm
1.75 mm
1.50 mm
Standard
Deviation
0.52
1 .04
0.53


108
the normal and anesthesia conditions. The mean difference
from the standard was 3.60 mm for the normal and 3.42 for the
anesthesia, Table 2.
The effect of anesthesia on subjects' ability to dis
criminate between pairs of jaw postures to the left of midline
did not differ noticably as a result of anesthesia. The mean
distance required was 1.69 mm for the normal condition and
1.62 mm for the anesthesia condition.
Anesthesia appeared to have somewhat of an enhancing
effect on subjects' ability to differentiate between pairs of
jaw positions in the anterior-posterior dimension. The mean
difference required was 1.06 mm for the control condition and
was reduced to 0.62 mm under anesthesia.
It might be suspected that the apparent enhancing effect
of anesthesia was actually the result of subjects' famili
arity with the tasks. In order to facilitate data collec
tion, that is, avoid losing subjects to follow-up testing,
the testing of each subject was completed in one session.
Therefore, all subjects were tested under the control condi
tion first and were retested subsequently under the experi
mental procedures. In order to balance presentation of ex
perimental tasks, two subjects performed the tasks under
anesthesia first and two subjects performed under anesthesia-
pressure first. Therefore, we might speculate that any im
proved performance under the experimental conditions was the
result of learning, while reduced performance would reflect
disruption of sensory ability.


122
oral airway, and not the nasopharyngeal airway, the path of
least resistance. Following successful management of velo-,
pharyngeal incompetency, the use of pressure might prove
beneficial towards returning jaw positioning to more normal
and natural limits if it does not do so spontaneously.
The clinical application of pressure to the TMJ might
be investigated in patients with apraxia of speech. The
patients have been demonstrated to have significantly reduced
abilities on a task of interdental space discrimination
when compared to either normal or aphasic patients (Rosenbek
et al ., 1973). The application of pressure may serve to
enhance mandibular position sense by making patients more
aware of condylar movement.
Since some alterations i r, mandibular posturing and
movement were observed under the experimental conditions and
the acoustic output remained undistorted, it might be sus
pected that the other oral articulators compensated to
produce undisrupted speech. Further study of the oral artic
ulators, oral air flow, and oral air pressure measures may
provide an understanding of the compensatory adjustments of
the speech articulators. Such information should provide an
insight into the retraining of articulatory patterns.


5
1. Body
2. Mental Protuberance
3. Mental Foramen
4. Oblique Line
9. Mandibular
5.
A1veolar
Process
6.
Ramus
7.
Condy1ar
Process
8.
Coro no i d
Process
Notch
Figure 1
Mandible: Left Lateral Aspect


103
Table 20
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /iki/
Measures
Vertical Displacement
Initial Vowel /i/
Consonant /k/
Final Vowel /i/
Condition Pairs
Normal/ Anesthesia/
Normal/ Anesthesia- Anesthesia-
Anesthesia Pressure Pressure
3.50/3.64 3.50/3.42 3.64/3.42
2.68/3.06 2.68/2.61 3.06/2.61
2.83/3.20 2.83/2.90 3.20/2.90
Horizontal Displacement
Initial Vowel /i/
Consonant /k/
Final Vowel /i/
4.69/4.09
4.69/4.24
4.40/4.09
4.69/4.39
4.69/4.40
4.40/4.40
4.09/4.39
4.24/4.40
4.09/4.40
Range of Vertical Movement
Initial Vowel to Final
Vowel 0.82/0.89
Initial Vowel to Consonant 0.96/0.97
Consonant to Final Vowel 1.04/1.12
0.82/0.67
0.96/0.89
1.04/0.59
0.89/0.67
0.97/0.89
1.12/0.59
Range of Horizontal Movement
Initial Vowel to Final
Vowel 0.44/0.52 0.44/0.52
Initial Vowel to Consonant 0.37/0.45 0.37/0.45
Consonant to Final Vowel 0.45/0.52 0.45/0.52
0.52/0.52
0.45/0.45
0.52/0.52
Duration of Production
Initial Vowel to Final
Vowel 11.78/11.00 11.78/10.55 11.00/10.55
Initial Vowel to Consonant 3.78/2.89 3.78/3.55 2.89/3.55
Consonant to Final Vowel 8.00/8.11 8.00/7.00 8.11/7.00
p <. 05


TABLE OF CONTENTS continued
CHAPTER PAGE
FIVE DISCUSSION 106
Anesthetization of the Auriculotemporal
Nerve 107
Effect of Pressure 114
Concl usi ons 120
APPENDIX 123
BIBLIOGRAPHY 150
BIOGRAPHICAL SKETCH
157


1. Temporomandibular ligament 3. Zygomatic Arch
2. Capsular Ligament 4. Condylar Process
(Articular Capsule)
Figure 6
Temporomandibular Ligament: Lateral View


LIST OF TABLES CONTINUED
Table Page
12 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Tip Elevation 88
13 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Dorsum Elevation 91
14 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
la,\l 93
15 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/el/ 94
16 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/aU/ 96
17 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
loll 97
18 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/ i si / 99
19 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/a- sa,/ 101
20 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/ i ki / 103
21 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/o-ka/ 104
22 The Amount of Jaw Opening (in mm) for the
Initiation of Each of Ten Tasks Under the
Normal and Pressure Conditions 118
23 Elevate Tongue Tip., 124
24 Elevate Tongue Dorsum..,, 127
25 Diphthong / a I / 130
26 Diphthong /el/ 132
27 Diphthong /aU/ 134
vi


14
1.
Articular Capsule
4.
Articular Disc
(Meniscus)
2.
Mandibular Fossa
5.
Upper
Synovial
Cavity
3.
Condylar Process
6.
Lower
Synovial
Cavity
Figure 5
Temporomandibular Articulation: Frontal View


154
Ricketts, R. M., Roentgenography of the temporomandibular
joint. In B. G. Sarnat (Ed.), THE TEMPOROMANDIBULAR JOINT,
Springfield, Illinois: Charles C Thomas (1964),
Ringel, R. L., Burk, K. W., and Scott, S. M., Tactile Percep
tion: form discrimination in the mouth. BRIT. J. DIS.
COMMUN., 3: 150-155 (1968).
Ringel, R. L., Saxman, J. H,, and Brooks, A. R., Oral Percep
tion: II mandibular kinesthesia, J, SPEECH HEARING RES.,
10: 637-641 (1967).
Ringel, R. L. and Steer, M. 0., Some effects of tactile and
auditory alterations on speech output. J. SPEECH HEARING
RES., 6: 369-378 (1963).
Rose, J. E. and Mountcastle, V., Touch and kinesthesia. In
J. Field (Ed.), HANDBOOK OF PHYSIOLOGY, Section 1, Vol 1,
American Physiology Society (1959).
Rosenbek, J. C., Wertz, R. T., and Darley, F. L., Oral sen
sation and perception in apraxia of speech and aphasia.
J. SPEECH HEARING RES., 16: 22-36 (1973).
Sarnat, B. G., THE TEMPOROMANDIBULAR JOINT, Springfield,
Illinois: Charles C Thomas (1964).
Schaerer, P., Legault, J. V., and Zander, H. A., Mastication
under anesthesia, HELV. ODONT. ACTO., 10: 130 (1966).
Schliesser, H. F. and Coleman, R. 0., Effectiveness of cer
tain procedures for alteration of auditory and oral tactile
sensation for speech. PERCEPT. MOTOR SKILLS, 26: 275-281
(1968) .
Scott, C. M. and Ringel, R. L. Articulation without oral
sensory control, J, SPEECH HEARING RES., 14: 804-818 (1971a).
Scott, C. M. and Ringel, R. L., The effects of motor and
sensory disruptions on speech: A description of articula
tion. J. SPEECH HEARING RES., 14: 819-828 (1971b).
Shepherd, R. W., A further report on mandibular movement.
AUST. DENT. J., 5: 337-342 (I960).
Sicher, H. and DuBrul, E., ORAL ANATOMY, St. Louis: C. V.
Mosby (1970).
Siirila, H. S. and Laine, P,, The tactile sensibility of the
peridontium to slight axial loadings of the teeth, ACTA
ODONT. SCAND. 21 : 41 5 (1 963),


89
when the tongue just released contact with the alveolar
ridge, and when the tongue was in its lowest posture prior
to elevation for the following trial. Analysis of these
three vertical measures revealed that no significant dif
ferences existed between the control and the anesthesia
condition, Table 12. However, further analysis revealed
that the vertical displacement of the jaw was reduced
significantly (p<.05) by the application of a light pres
sure. The amount of horizontal displacement, measured at
these same three points, was not significantly altered under
either of the experimental conditions.
The range of mandibular movement in the vertical and
horizontal planes was calculated between tongue contact with
the alveolar ridge and at the point when the tongue was in
its lowest posture, between the time the tongue contacted the
alveolar ridge and released contact, and between the time the
tongue released contact and assumed its lowest posture. Sta
tistical analysis of these data revealed no significant dif
ferences between any of the three pairs of conditions.
Therefore, the range of jaw movement was not altered by anes
thesia of the right auriculotemporal nerve, nor was the range
of movement altered by a subsequent application of pressure
to the left TMJ capsule.
The amount of time between these same three points was
calculated also. Although the duration of production appeared
increased by the experimental procedures, only the time re
quired to complete the move from tongue contact to tongue re
lease was significantly increased by the application of


143
Table 30 continued
Vowel-Consonant-Vowel /asa/
Summary:
Analysis of
Condition Repeated Measures
Anes thesia/
Measure
Subject
Normal
Anesthesia
Pressure SS
df
MS
F
Thirteen:
A
7.82
7.37
8.04
Time from
B
6.70
6.48
6.25
\l-\ to V2
C
8.04
7.82
8.26
Mean
7.52
7.22
7.52 1.18
2
0.59
1.133
S.D.
0.41
0.39
0.64
Fourteen:
A
2.90
2.90
3.35
Time from
B
2.90
2.90
2.90
V1 to C
C
3.35
4.13
3.80
Mean
3.05
2.98
3.35 1.56
2
0.78
1 .931
S.D.
0.15
0.07
0.26
Fifteen:
A
4.69
4.47
4.69
Time from
B
3.80
3.57
3.35
C to V,
C
4.69
4.69
4.47
Mean
4.47
4.24
4.17 0.96
2
0.48
0.794
S.D.
0.34
0.34
0.41


68
Table 2
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard
Condition
Subject
Normal
Anesthetized
Anesthetized and Pressure
A
2.4 mm
4.4 mm
0.8 mm
B
4.1
2.7
3.6
C
1 .9
4.1
7.1
D
6.2
2.9
1 .5
Means
3.65 mm
3.52 mm
3.25 mm
Standard
Deviation
1.78
0.96
2.83


1 26
Table 23 continued
Elevate Tongue Tip
Measure
Condition
Anesthesia/
Subject Norma 1 Anesthesia Pressure
Summary :
Analysis of
Repeated Measures
SS df MS F
Twelve:
A
0.
,67
1 .
,67
Range
of
B
0.
.00
1 .
,01
Horizontal
C
0.
.00
0.
.67
Movement
D
2.
.01
1 .
.01
from
TR
Mean
0,
.67
1 .
.09
to LT
S.D.
0.
.48
0.
.21
Thirteen:
A
6.
, 70
6.
.03
T i me
from
B
12.
.73
17.
.08
TC to
LT
C
11 .
.39
16.
.41
D
24,
.12
28.
.81
Mean
13.
.74
17.
.08
S.D.
3,
.70
4,
.66
Fourteen:
A
4
.69
3.
.02
T i me
from
B
6
.03
11 ,
.06
TC to
TR
C
5 .
. 36
9 ,
.72
D
10.
.72
15,
.41
Mean
6.
.70
9,
.80
S.D.
1 ,
.37
2.
.57
Fifteen:
A
2.
.01
3.
.02
Time
from
B
6.
. 70
6.
.03
TR to
LT
C
6
.03
6.
.70
D
13,
.40
13.
.40
Mean
7.
.04
7.
.29
S.D.
2
.36
2.
.19
1.01
1 .01
0.67
1.01
0.92 1.58 2 0.79 0.630
0.08
10.39
16.75
14.07
24.80
16.50 114.10 2 57.04 3.893*
3.06
5.02
8.71
8.38
12.06
8.54 86.58 2 43.29 4.485*
1 .44
5.36
8.04
5.70
12.73
7.96 8.08 2 4.04 1.177
1.70


THE ROLE OF THE
TEMPOROMANDIBULAR JOINT
IN MEDIATING PERCEPTION
OF MANDIBULAR POSITION
by
JOHN EDWARD RISKI
A DISSERTATION PRESENTED TO THE GRADUATE COUNCIL OF
THE UNIVERSITY OF FLORIDA
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE
DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1976

ACKNOWLEDGEMENTS
The author wishes to extend his sincerest gratitude
to his committee members, Drs. Ed Hutchinson, Bill Williams
Chick LaPointe, and Parker Mahan, Throughout the project
they provided continued encouragement and assistance.
Acknowledgement is extended also to Dr. Joe Meier and
Mr. Harry Canter of Millersville State College, Millersvill
Pennsylvania and to Dr. Paul Ross, Franklin and Marshall
College, Lancaster, Pennsylvania. These gentlemen were
instrumental in completing the statistical analysis of the
data.
Finally, the author wishes to acknowledge the assist¬
ance of Linda McCullers, who aided in all stages of the
study. It is to Linda that this study is dedicated.

TABLE OF CONTENTS
PAGE
ACKNOWLEDGEMENTS ii
LIST OF TABLES v
LIST OF FIGURES viii
ABSTRACT ix
CHAPTER
ONE INTRODUCTION 1
Anatomy and Physiology 2
Review of Literature 19
TWO STATEMENT OF PROBLEM 38
Statement of Purpose 39
Specific Objectives 39
THREE METHODS AND PROCEDURES 41
Subject Selection 41
Experimental Tasks 41
Experimental Procedures 51
Filming Procedures 54
Procedures for Data Collection 55
FOUR RESULTS 65
Analysis of Perceptual Tasks and Connected
Speech 65
Analysis of Speech Tasks and Nonspeech
Oral Movements 86

TABLE OF CONTENTS - continued
CHAPTER PAGE
FIVE DISCUSSION 106
Anesthetization of the Auriculotemporal
Nerve 107
Effect of Pressure 114
Concl usi ons 120
APPENDIX 123
BIBLIOGRAPHY 150
BIOGRAPHICAL SKETCH
157

1
2
3
4
5
6
7
8
9
10
11
LIST OF TABLES
Page
Individual Performance Scores and Group Means,
Ranges, and S.D.’s for Duplication of Interdental
Space Task: Range of Jaw Position for Ten Trials...66
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard 68
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination 70
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination 71
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Left 73
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Left 74
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Ri ght ...75
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Lateral Jaw Position Discrimination to the
Right 76
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination 78
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Anterior-Posterior Jaw Positions 79
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination 80
v

LIST OF TABLES CONTINUED
Table Page
12 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Tip Elevation 88
13 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Tongue Dorsum Elevation 91
14 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
la,\l 93
15 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/el/ 94
16 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
/aU/ 96
17 Results of Newman Keuls Analysis: Condition
Pairs for Measures of Diphthong Production:
loll 97
18 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/ i si / 99
19 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/a- sa,/ 101
20 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/ i ki / 103
21 Results of Newman Keuls Analysis: Condition
Pairs for Vowel-Consonant-Vowel Production:
/o-ka/ 104
22 The Amount of Jaw Opening (in mm) for the
Initiation of Each of Ten Tasks Under the
Normal and Pressure Conditions 118
23 Elevate Tongue Tip., 124
24 Elevate Tongue Dorsum..,, 127
25 Diphthong / a I / 130
26 Diphthong /el/ 132
27 Diphthong /aU/ 134
vi

LIST OF TABLES CONTINUED
Table Page
28 Diphthong /D\/ 136
29 Vowel-Consonant-Vowel /i si / 138
30 Vowel-Consonant-Vowel /asa-/ 141
31 Vowel-Consonant-Vowel /i ki/ 144
32 Vowel-Consonant-Vowel /oXa./ 147
vi i

LIST OF FIGURES
FIGURE PAGE
1 Mandible: Left Lateral Aspect ..5
2 Mandible: Left Medial Aspect 7
3 Muscular Control of Mandibular Movement. 10
4 Temporomandibular Articulation: Sagittal View. ...13
5 Temporomandibular Articulation: Frontal View 14
6 Temporomandibular Ligament: Lateral View 17
7 Sphenomandibular and Stylomandibular Ligaments:
Medi al View 18
8 Acrylic Blocks for Assessing Interdental
Thickness Discrimination 44
9 Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination 45
10 Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination 48
11 Cephalostat and Pressure Device 53
12 Defined Measurements and Their Associated
Positive and Negative Values 57
13 Means, Ranges, and S.D.'s of Vertical Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4) 83
14 Means, Ranges, and S.D.'s of Horizontal Jaw
Positions Under Three Conditions for 17
Sounds Selected From a Connected Speech
Sample (N = 4) 85
v i i i

Abstract of Dissertation Presented to the Graduate Council of
the University of Florida
in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy
THE ROLE OF THE
TEMPOROMANDIBULAR JOINT
IN MEDIATING PERCEPTION
.OF MANDIBULAR POSITION
by
John Edward Riski
August, 1976
Chairman: Edward C. Hutchinson
Cochairman: William N. Williams
Major Department: Speech
Measures of mandibular positioning and movement are
described for a series of selected speech and nonspeech tasks
under normal and experimental conditions. The purpose of the
study was to evaluate the role of the sensory mechanism of the
temporomandibu 1ar joint in mediating perception of mandibular
position by 1) measurement of the positioning of the mandible
during selected speech and nonspeech tasks following unilateral
auriculotemporal nerve block, and 2) measurement of the position¬
ing of the mandible during selected speech and nonspeech tasks
during the application of a light pressure to the contralateral
temporomandibular joint capsule.

Four young adult males, with normal occlusion and no
history of temporomandibular joint dysfunction, served as sub¬
jects. Each subject completed all of the tasks under a nor¬
mal condition, anesthetization of the right auriculotemporal
nerve, and anesthesia with a light pressure (one to two
pounds per square inch) applied to the left temporomandibular
joint capsule.
Each subject completed tasks designed to test his abil¬
ity to perceive the position of his mandible in the superior-
inferior, 1 atera1-medial, and anterior-posterior dimensions and
discriminate differences in weights of capsules held between
the teeth. In addition, each performed a series of tasks re¬
quiring speech sound production and tongue elevation. The
anesthetization procedure utilized in this study did not appear
to disrupt subjects' perception of mandibular position for
any of the tasks in or significantly alter the positioning
of the mandible for the speech sample used. However, the
application of pressure disrupted subjects' ability to dis¬
criminate between pairs of jaw positions to the right of
midline. Further, the application of pressure significantly
reduced the amount of jaw opening when the jaw opening was
observed to be greater than ten millimeters for the normal
condition.
The results of this study were interpreted to suggest
that the sensory mechanism of the temporomandibular joint, at
least the auriculotemporal nerve, has a minimal role in re¬
gulating the positioning and movement of the mandible.
x

Further, these data suggested that pressure to the TMJ, on
the order of one to two pounds per square inch, inhibits the
translatory motion of the condyle process.
x 1

CHAPTER ONE
INTRODUCTION
The oral structures primarily responsible for normal
speech articulation include the lips, tongue, velum, teeth,
and mandible. Considerable information is available rela¬
tive to the normal placement and posture of these structures
for the production of normal speech elements. In addition,
several studies have demonstrated that there are identifiable
alterations in the speech signal following experimental
anesthetization of the oral structures (McCroskey, 1958;
McCroskey et a 1â– , 1 959 ; Ringel and Steer, 1 963; Schliesser
and Coleman, 1 968; Gammon et al . , 1971; and Scott and Ringel,
1971a) .
Further, a growing body of literature exists which deals
with the assessment of mandibular function. Specific varia¬
tions in mandibular placement have been observed for the pro¬
duction of certain speech sound elements (Kent and Moll, 1972
and Owens, 1973). The independent, yet complimentary, actions
of the tongue and the mandible and the lower lip and the man¬
dible have been recently described (Kent, 1972 and Sussman
et al., 1973). Other studies have demonstrated that subjects'
ability to perceive mandibular position for nonspeech tasks
is disrupted by anesthetization of the temporomandibular joint
(TMJ) capsule (Thilander, 1961). It has been reported also
that disruption in the perception of mandibular position,
1

2
caused by unilateral anesthetization of the TMJ capsule, can
be normalized by applying a painless pressure to the contra¬
lateral capsule (Larsson and Thilander, 1964). A review of the
literature has failed to reveal any further information rela¬
tive to the influence of anesthetization of the TMJ on the
control of mandibular position during speech function.
Therefore, the purpose of this study is basically
twofold: 1) to determine the effect of unilateral anestheti¬
zation of the TMJ on normal subjects' ability to position the
mandible during selected speech and nonspeech tasks and
2) to determine the effect of a painless pressure administered
to the TMJ contralateral to the one anesthetized on subjects'
ability to position the mandible during the same selected
speech and nonspeech tasks.
Anatomy and Physiology
The mandible, or lower jaw, is comprised of a horizontal
portion, the body, and two vertical portions, the rami. The
rami unite interiorly with the ends of the body. Superiorly,
the rami articulate with the temporal bone by way of the TMJ.
The complex movements of the mandible are made possible by
two groups of muscles, the muscles of mastication and the
suprahyoid muscles, and by the intricate function of the TMJ'S.
The purpose of this discussion is to describe the anatomy and
the physiology of the mandibular complex including the mandible,
the muscles that influence its movement and mandibular articu¬
lation with the skull. The following account relies primarily
on the description of Enlow (1971), Gray (1959), Mahan (1967),

3
Sicher and DuBrul (1970), and Zemlin (1968).
Handi ble: Origin and Growth
The body of the mandible is horseshoe shaped and ex¬
tends upward and backward on both sides into the mandibular
ramus. The ramus extends upwards from the mandibular angle
and ends in two processes, the anterior, muscular coronoid
process and the posterior, articular condylar process. The
mandible is formed embryologically from the first branchial
arch, which is known also as the mandibular arch. The first
arch ultimately gives rise to the lower lip, the muscles of
mastication, the mandible, the anterior portion of the tongue,
and some of the middle ear structures. The mandibular arch
is joined with the maxillary processes at the extreme lateral
and rostral margins. The progressive anterior fusion between
these two processes reduces the width of the primative oral
fissure and forms the cheeks. At birth, the mandible is di¬
vided into halves. It contains the alveoli for the deciduous
dentition. The angle of the ramus with the mandibular plane
is obtuse, about 170° . Shortly after birth, the two halves
of the mandible become fused at the symphysis, beginning from
below. Fusion is usually complete by the first year. With
growth, the angle of the mandible becomes less and less obtuse.
At four years of age, it is about 140° and in the adult man¬
dible, the angle is about 110° -120° .
The growing mandible enlarges in a forward and downward
manner with respect to the cranial base. However, the actual
course of growth proceeds in a complex process of bone

4
deposition and resorption predominantly in the posterior
and superior direction. The overall growth of the mandible
is associated with regional growth areas, which include
virtually all of the inner and outer surfaces of the mandi¬
ble. These areas of growth include the neck of the condyle,
the coronoid process, the lingual tuberosity, the trihedral
eminence, and the chin. The regional growth movements are
concerned with a continuous process of relocation in which
the various local parts become shifted progressively in order
to maintain constant positions relative to the remainder of
the growing enlarging mandible as a whole.
Adult Mandible
As noted earlier, the mandible consists of a horseshoe
shaped body, which continues upward and backward into the
mandibular ramus. The ramus ends in two processes, the con¬
dylar and the coronoid. Figures 1 and 2 illustrate the lat¬
eral and medial aspects respectively of the adult mandible.
The mental symphysis joins the left and right mandibu¬
lar bodies. Externally, it appears as a faint ridge. The
ridge divides interiorly and encloses a triangular eminence,
the mental protuberance, which is depressed in the center,
but is raised on either side to form the mental tubercles.
The incisive fossa are the depressions lateral to the sym¬
physis and just below the incisor teeth. The incisive fossa
are the origin of the mentalis and a small portion of the
orbicularis oris muscles. The mental foramen is found below
the second premolar tooth, midway between the inferior and

5
1. Body
2. Mental Protuberance
3. Mental Foramen
4. Oblique Line
9. Mandibular
5.
A1veolar
Process
6.
Ramus
7.
Condy1ar
Process
8.
Coro no i d
Process
Notch
Figure 1
Mandible: Left Lateral Aspect

6
superior borders of the body. The mental vessels and nerve
exit at the foramen. The oblique line is the faint ridge,
which proceeds posteriorly and superiorly from the mental
foramen becoming continuous with the anterior border of the
ramus. It provides attachments for the quadratus labii
inferior and triangularis; the platysma attaches just infer¬
ior to the oblique line. The superior surface of the man¬
dibular body is the tooth-bearing alveolar process. It is
hollowed into numerous cavities (alveoli) for the reception
of teeth. The alveolar process resorbs with tooth loss re¬
sulting in a reduced vertical dimension of the mandible.
The ramus of the mandible is directed superiorly from
the posterior portion of the body of the mandible. The ramus
divides superiorly into the condylar and the coronoid pro¬
cesses. These processes are separated by the mandibular or
the semilunar notch. The anterior, coronoid process serves
as the point of attachment for the temporalis muscle. The
condyloid process frames the mandibular head, which articu¬
lates with the mandibular fossa of the temporal bone by way
of the TMJ. The lateral surface of the ramus gives attach¬
ment to the masseter muscle throughout nearly its whole ex¬
tent.
The medial aspect of the mandible is illustrated in
Figure 2. Two small posteriorly directed spines are pro¬
jected near the symphysis. These ridges or mental spines
are placed one above the other and serve as the origin for
the genioglossus muscle. The geniohyoid muscle originates
just inferior to the mental spines. Inferior and lateral to
the mental spines are the attachments for the anterior belly

7
1 .
2.
Mental Spines 3.
Mylohyoid Line 4.
5. Angle of Mandible
Mandibular Foramen
Mylohyoid Groove
Figure 2
Mandible: Left Medial Aspect

8
of the digastricus . The mylohyoid line extends posteriorly
and superiorly from the interior part of the symphysis. The
mylohyoid originates along this line. The superior pharyn¬
geal constrictor originates, in part, from the posterior por¬
tion of the line near the alveolar margin.
The medial surface of the ramus is marked near its
center by the mandibular foramen for the entrance of the in¬
ferior alveolar vessels and nerve. The mylohyoid groove
runs obliquely inferiorly and anteriorly from the foramen
and houses the mylohyoid vessels and nerve. The angle of
the mandible provides attachments for the masseter laterally
and the internal pterygoid on its medial aspect. The internal
aspect of the ramus also provides attachments for several
ligaments. The attachments and ligaments will be discussed
later as a group.
Mandibular Musculature
The mandible is influenced in its movements and posi¬
tioning by all of the muscles that attach to it. Further¬
more, all mandibular muscles are active in all movements of
the mandible as their roles shift from movers to balancers
to holders (Sarnat, 1964). Two groups of muscles are of
prime concern. They are the muscles of mastication and the
suprahyoid muscles. Two other group of muscles are of se¬
condary importance. They are the infrahyoid muscles, which
serve to stabilize the hyoid bone and the cervical column
and the post vertebral muscles, which serve to stabilize the
cranium, (Sicher and DuBrul, 1970 and Perry, 1973). The

9
focus of this discussion will be the two primary muscle
groups. The mandibular musculature can be divided by func¬
tion or by muscles groups. For the purpose of this discus¬
sion the musculature will be considered in muscle groups.
The direction of mandibular movement by each of the muscles
is illustrated in Figure 3.
Muscles of Mastication
Mas seter. This muscle originates along the zygomatic
arch and zygomatic process and inserts along the ramus, the
coronoid process and the angle of the mandible. It is in¬
nervated by the mandibular branch of the Trigeminal nerve and
serves to elevate the mandible.
Temporalis. This muscle has its origin on the floor of
the temporal fossa and the temporal facia. It inserts along
the anterior border of the coronoid process and the anterior
border of the ramus of the mandible. It is also innervated
by the mandibular branch of the Trigeminal nerve. It func¬
tions to elevate and retract the mandible.
External Pterygoid (Lateral). This muscle originates
from the greater wing of the sphenoid and the lateral sur¬
face of the lateral pterygoid plate. It inserts on the
anterior portion of the neck of the condylar process and the
meniscus of the mandibular joint. It is innervated by the
mandibular branch of Trigeminal nerve and serves to protrude
the mandible and pull the articular disc anteriorly. It
also assists in the rotary movement of the mandible for
chewing.

Te Te Te
10
Muscles of Mastication
Suprahyoid Muscles
M:
Masseter
Mh:
Mylohyoid
Te:
T emporalis
Gh:
Geniohyoid
EPy:
External Pterygoid
Da b:
Anterior Belly
of Digastric
IPy:
Internal Pterygoid
Figure 3
Muscular Control of Mandibular Movement
After Cole (1971)

11
Internal Pterygoid (Medial). The origin of this muscle
is along the lateral pterygoid plate and the perpendicular
plate of the palatine bone. Insertion into the mandible is
along the posterior medial surface of the ramus and the
angle of the mandible, and innervation is from the mandibu¬
lar branch of the Trigeminal nerve. It serves to protrude
and to elevate the mandible and also assists in the rotary
movement for chewing.
Suprahyoid Muscles
My 1ohyoid . This muscle originates along the mylohyoid
line of the mandible and inserts along the median raphe from
the chin to the hyoid bone. It is innervated by the mylo¬
hyoid branch of the Trigeminal. It elevates the hyoid bone
and the base of the tongue, but also assists in depressing
the mandible.
Geniohyoid â–  The mental spine of the mandible is the
origin of this muscle. It inserts on the body of the hyoid
bone and is innervated by the first and second cervical
nerves through the Hypoglossal nerve. It functions to ele¬
vate the hyoid bone and move it anteriorly as well as to de¬
press the mandible.
Digastricus (anterior belly). The anterior belly of
the Digastricus originates from the inner surface of the
mandible near the symphysis. It inserts into the inter¬
mediate tendon of the hyoid bone. It is innervated by the
mylohyoid branch of the Trigeminal nerve. It also serves
to elevate the hyoid bone and to depress the mandible.

12
Temporomandibular Articulation
The TMJ is unique among all the joints of the human
body. It is a gynglmoarthrodial (sliding hinge) joint.
Unlike most articulating surfaces, the TMJ is not covered
by hyaline cartilage, but rather, is covered by an avascu¬
lar, fibrous protein, collagen. Also unique to the TMJ
articulation is the fact that the two articulating complexes
house teeth, whose shape and position guide the joint when
teeth come to occlusion. Finally, the bilateral articula¬
tion with the skull restricts certain mandibular motions,
such as lateral movement. The sliding and hinge movement
of the TMJ is possible because of an articular disc or
meniscus interposed between the temporal bone and the con¬
dylar process of the mandible, thus dividing the articular
space into an upper and a lower compartment. Figure 4
illustrates a sagittal section of the TMJ articulation. The
hinge or rotational movement occurs between the condyle and
articular disc while the sliding or translational movement
occurs between the temporal bone and the meniscus.
The articular disc is a thin oval plate with tight
lateral and medial attachments to the condyle, an elastic
posterior attachment to the tympanic plate of the temporal
bone and an anterior attachment to the articular capsule
and to the lateral pterygoid muscle. The shape of the disc
is such that it accommodates itself with the surface of the
condylar process below and temporal bone above.
The TMJ is surrounded by a thin articular capsule,
which is illustrated in Figure 5. The capsule is loosely

13
1.
Mandibular
Condyle
4.
Upper
Synovial
Cavity
2.
Articular
Disc
(Meniscus)5.
Lower
Synovial
Cavity
3.
Temporal Bone
6.
Mandibular Fossa
7. Articular Eminence
Figure 4
Temporomandibular Articulation: Sagittal View

14
1.
Articular Capsule
4.
Articular Disc
(Meniscus)
2.
Mandibular Fossa
5.
Upper
Synovial
Cavity
3.
Condylar Process
6.
Lower
Synovial
Cavity
Figure 5
Temporomandibular Articulation: Frontal View

15
attached to the articulatory surfaces of the mandibular
fossa and to the neck of the condylar process laterally,
medially, and anteriorly. The capsule thickens laterally
into the temporomandibular ligament which will be included
in the following discussion. Except for the thickening, the
capsule is loosely organized in its lateral aspect and the
lateral aspect of the anterior wall. The medial aspect of
the anterior wall has attachments to the articular disc and
to the lateral pterygoid muscle. The medial and posterior
walls of the capsule are present but also loosely organized.
In translational movements, the condyle is pulled anteriorly
onto the articular eminence. As the meniscus is tightly
attached to the condyle while having only an elastic attach¬
ment posteriorly to the tympanic plate of the temporal bone,
the meniscus translates anteriorly with the condyle. How¬
ever, the attachment of the meniscus to the condyle is not
rigid enough to prevent movement of the condyle against the
meniscus in a horizontal plane during hinge as rotary move¬
ment of the mandible.
The first stage of mandibular depression is a simple
hinge action, and only the lower compartment is used as the
head of the condyle rotates along the inferior surface of
the articular disc. As the mandible is further depressed,
translation begins between the disc and the articular emi¬
nence resulting in forward displacement of the condyle.
There are three ligaments which participate in TMJ
articulation. These ligaments are now believed to function
in limiting jaw movement at maximum open jaw positions and

16
to provide proprioceptive input to the central nervous
system via their Golgi tendon organs. These ligaments are
illustrated in Figures 6 and 7.
The temporomandibular ligament is comprised of two short
bundles, one anterior to the other. As noted earlier, this
ligament is a thickened portion of the articular capsule. The
ligament is attached superiorly to the zygomatic arch and
interiorly to the lateral, posterior surface of the condylar
process.
The sphenomandibular ligament is a remnant of Mechel's
cartilage. The ligament arises from the angular spine of the
sphenoid bone and spreads fanlike downward and outward
finally attaching to the mandible ar the lingula of the man¬
dibular foramen.
Lastly, the stylomandibular ligament extends from near
the apex of the styloid process of the temporal bone to the
angle and posterior border of the ramus of the mandible.
Sensory innervation to the TMJ capsule is supplied
primarily by the auriculotemporal nerve of the mandibular
branch of the Trigeminal nerve. Small slips of the masseteric
and posterior deep temporal nerve also supply the capsule
anteriorly.
Histological studies have provided further information
regarding the sensory innervation of the capsule. Thilander
(1961) demonstrated that the posterior and lateral aspects
of the capsule are the most richly innervated, while the
anterior and medial aspects are sparsely innervated and the
articular disc lacks any sensory innervation. Thilander found

1. Temporomandibular ligament 3. Zygomatic Arch
2. Capsular Ligament 4. Condylar Process
(Articular Capsule)
Figure 6
Temporomandibular Ligament: Lateral View

18
6
1.
Sphenomandibular Ligament
4.
Stylomandibular Ligament
2.
Angular Spine of Sphenoid
5.
Styloid Process
3.
Mandibular Foramen
6.
Angle of Mandible
Figure 7
Sphenomandi bul ar and Stylomandibular Ligaments:
Medial View

19
four types of nerve endings in the capsule. Free nerve
endings were the most abundant. Organized endings such as
Ruffini endings, Golgi tendon organs, and the Vater-Pacini
corpuscles are represented, but only sparsely.
Investigations of the role of joint receptors in
perception of position sense and kinesthesis by Mountcastle
and Powell (1959) provide further information of the sensory
capabilities of the TMJ joint receptors. They indentified
two types of slowly adapting nerve endings. These endings
discharged at a steady rate that was influenced only by the
angle of the joint. Individual receptors responded to arcs
of 15 to 20 degrees. Thus, they functioned as absolute
detectors of joint angle. The two groups of endings were
the spray type Ruffini endings and the Golgi tendon organs,
both of which are present in the TMJ.
The blood supply to the TMJ capsule is through the
superficial temporal and maxillary arteries posteriorly and
from the twigs of the masseteric artery anteriorly. The
articular disc, which is avascular in its center, has an
unusually rich plexus of veins on the periphery. The plexus
serves to equalize pressure in the tissues by filling and
emptying as the condyle rocks rythmically forward and back¬
ward in chewing.
Review of Literature
The purpose of this review is to present the current
understanding of oral sensation and perception with specific
reference to mandibular kinesthesia. In addition, mandibular

20
function will be discussed in reference to the physiological
processes of mastication, deglutition, and speech.
Sensory Interruption
Fairbanks (1954) proposed a feedback loop theory of
speech production in which he hypothesized that tactile and
kinesthetic feedback, in addition to auditory feedback, are
necessary for normal speech production. The importance of
auditory feedback for speech production is supported by the
results of investigations which have demonstrated that de¬
laying the air borne auditory signal (delayed auditory feed¬
back) of normal speakers typically results in an aberrant
speech pattern characterized by dysfluency, general articu¬
lation inaccuracy and modification of speech sound duration,
the fundamental frequency and the sound pressure level (Lee,
1950; Black, 1951; and Fairbanks, 1955). The need for tactile-
kinesthetic information has been supported by researchers who
have demonstrated that there is a relationship between oral-
sensory integrity and articulation proficiency (McCroskey,
1958; McCroskey et al., 1959; Ringel and Steer, 1963: Schliesser
and Coleman, 1968; Thompson, 1969; Gammon et al., 1971; Scott
and Ringel, 1971a; Scott and Ringel, 1971b; Horii et alâ– , 1972;
and Borden, 1973).
The task of oral stereognosis, which involves the iden¬
tification of plastic shapes presented intra-orally has evolved
recently as a possible indicator of oral sensory integrity.
Research has indicated that the subjects' performance

21
on this task, which has been suggested to involve intra-oral
movements similar to those in speech production, is severely
disrupted by mandibular block anesthesia (Schliesser and
Coleman, 1968 and Thompson, 1969).
A positive relationship between speech skills and oral
stereognosis has been established also (Moser et al., 1967;
Ringel et al â– , 1968; Weinberg 1 970; Fucci and Robertson,
1971; and McNutt, 1973). These studies have demonstrated that
articulatory defective individuals without any known structural
or organic pathologies perform poorer on tasks of oral stere¬
ognosis than do their normal speaking counterparts. Further
evidence of a positive relationship between speech skills and
oral stereognosis is offered by Bishop et al. (1973). These
researchers compared the performance of manually educated
deaf individuals and to normal hearing speakers on a task of
oral stereognosis. The experimental group made more errors
on this task as well as making different types of errors as
compared to the other two groups. The authors suggested that
orosensorimotor functions develop, in part, through the prac¬
tice of speech skills.
A discussion of sensory disruption is necessarily
followed by a discussion of feedback systems. The researchers
who initially investigated articulation under nerve block
anesthesia assigned monitoring abilities for any uneffected
articulatory events to other channels, presumably undisturbed
by the anesthesia. This reflects the view that all articula¬
tory activities are monitored by some sensory channel. This

22
view of a closed-loop feedback system was reported by
MacNeilage (1970) and Abbs and Netsell (1973).
Hixon and Hardy (1964), on the other hand, proposed
that speech movements were programmed. This view was
supported by Kent (1973) who found time intervals between
articulatory events were too short to accommodate the use of
feedback. Kent (1973) proposed that speech is more likely
operating under open-loop control or that speech is pre¬
programmed centrally. He postulated that feedback might be
employed in a reset capacity to allow for occasional
adjustment of the motor program.
Although much of the discussion regarding feedback
control is theoretical, interpretation of current evidence
suggests that both closed-loop and open loop control systems
are actively involved in motor control of speech (Putnam
and Ringel, 1972 and Abbs, 1973). Thus, after a speech
sequence is triggered initially as a unit, peripheral sensory
mechanisms make fine adjustments. Such a theory may help
explain why only minor distortions of the speech signal are
observed when bilateral mandibular blocks are performed.
Mandibular Position - Movement
The limited amount of research on mandibular positioning
can be attributed to the absence of convenient and accurate
transduction techniques. Geissler (1971) outlined three
requirements for instrumentation. It should be able to record
a large number of patients, should not interfere with normal
mandibular movements, and should allow continuous recording
during mandibular movement.

23
Within the past several years, a number of techniques
have been developed to record mandibular movement during a
variety of functions. The techniques include cinefluoro-
graphy (Jankelson et a 1., 1 953), the Case Gnathic Replicator
(Gibbs et al., 1966), the Perspex screen (Atkinson and
Shepherd, 1 955), Photoelectric Mandi bu 1ography (Gillings
and Graham, 1964), and strain gauge devices (Sussman and
Smith, 1970). There are advantages and disadvantages to each
method. Some provide information of only two planes of
movement (Photoelectric Mandibulography, cinef1uorography,
and the perspex screen). Others are expensive to operate
(Case Gnathic Replicator) or appear to interfere with normal
mandibular movement (strain gauges). Nonetheless, with this
variety of instrumentation, an understanding of mandibular
movement is developing.
Several measurement strategies have been developed
recently to study mandibular kinesthesia. These techniques
include duplicating an interdental space (Thilander, 1961)
and several methods of assessing interdental space discrim¬
ination (Ringel et al., 1967; Williams and LaPointe, 1972;
and Williams et al., 1974). As a result of available
instrumentation and test methodology, there is a growing
body of literature on assessment of mandibular function.
Researchers have begun to define quantitatively mandibular
kinesthesia and mandibular function for the biophysiological
processes of the mastication, deglutition, and speech. Initial
attempts also have been made to define the sensory mechanism
responsible for

24
neuromuscular control of mandibular movement and positioning
for these processes. The following literature review presents
the current understanding of mandibular kinesthesia and man¬
dibular and TMJ function for the processes of deglutition,
mastication, and speech.
Mandibular kinesthesia
Oral kinesthesia has been defined by Ringel et al.
(1967) as the sense by which muscular motion, weight, and po¬
sition of an oral structure is perceived. Rose and Mountcas-
tle (1959) previously established that intact joint receptors
and central nervous system relay networks are required for
kinesthesia. Mountcastle and Powell (1959) confirmed that
specific joint endings with cortical projections respond to
absolute degrees of arc or joint angles. Thus, defining
mandibular kinesthesia as the sense of perceiving the posi¬
tion, motion, and weight of the mandibular structure appears
completely acceptable. Research indicates, however, that
Subjects' performance on tasks of interdental thickness dis¬
crimination (mandibular position) is unrelated to their per¬
formance on tasks of interdental weight discrimination and
that different receptors may be responsible for the percep¬
tion of mandibular position and the interdental perception
of weight (Williams and LaPointe, 1972).
The study of mandibular kinesthesia in normal human
individuals has concentrated primarily on subjects' ability
to discriminate differences in mandibular positions. Although
instrumentation has varied, the results reported by various

25
investigators have been remarkably similar. Thilander (1961)
described a task which required subjects to choose a random
jaw position between the rest position and maximum jaw open
position and then to replicate that position ten times. Under
normal conditions, the subjects came within plus or minus
1.6 mm of duplicating this position over 20 trials. Ringel
et al . ( 1 967) used a modified vernier-type caliper placed
between the biting surfaces of the upper and lower central
incisors. Their results indicated that absolute difference
limen values are relatively independent of the degree of
mouth opening. They reported an average difference limen of
2.04 mm. Williams and LaPointe (1972) and Williams et al.
(1974) used pairs of plastic blocks and pairs of plastic
wedges to attain difference limens. With the use of pairs
of plastic blocks, they reported an average difference limen
of 1.91 mm. They concluded also that interdental thickness
discrimination was independent of mouth opening. Williams
et al, (1974) used pairs of plastic wedges (the wedges
required quided mandibular motion to a given position), to
establish difference limens and reported an average difference
limen of 1.37 mm. They suggested that the lower difference
limen, using the wedges, reflected the mandibular movement
required by the instrumentation and provided subsequent
activation of additional sensory receptors in the TMJ.
Further understanding of the sensory mechanism of
mandibular kinesthesia has been gained from other studies
of interdental thickness discrimination. Originally, the

26
receptors responsible for mediating the sense of mandibular
position were thought to be housed in the TMJ capsule, muscles
of mastication, or possibly the periodontal ligament
(Thilander, 1961). Studies of interdental thickness discrim¬
ination comparing the performance of dentulous and edentulous
subjects suggest that the periodontal ligament is not respon¬
sible for perception of mandibular position (Manly et al., 1952;
Kawamura and Watanabe, 1960; Woodford, 1964; and Siirila and
Laine, 1963). Again, although instrumentation and methodology
differed slightly, several groups of researchers have reported
that the ability to detect thicknesses or difference in thick¬
nesses does not differ appreciably between dentulous and
edentulous subjects. Discrimination of thickness appears
equally good between natural incisors and natural molars
(Kawamura and Watanabe, 1960 and Siirila and Laine, 1963).
Neither is there any significant difference in perception
threshold when both upper and lower antagonistic teeth are
anesthetized (Siirila and Laine, 1363), nor when the alveolar
mucosa is topically anesthetized (Manly et alâ–  , 1 952).
Woodford (1964) found that edentulous subjects performed
equally as well on a task of thickness discrimination with or
without their dentures.
The TMJ's sensory mechanism has been implicated as
performing an active role in mandibular kinesthesia in re¬
search by Thilander and her colleagues. Thilander (1961)
hypothesized that disrupting the sensory mechanism would impair
perception of mandibular position. She developed a task for

27
assessing mandibular kinesthesia which required subjects to
choose an arbitrary jaw position between mandibular rest
position and maximum opened jaw position and then attempt
to replicate that position ten times in close succession.
From the results of a series of experiments, including uni¬
lateral and bilateral anesthetization of the TMJ capsules
and anesthetization of the inferior nerve, she concluded
that the TMJ capsule is responsible , at least in part, for
mediating perception of mandibular position. More speci¬
fically, subject performance varied from normal only under
conditions of unilateral and bilateral anesthetization of the
TMJ capsule. Subject performance was disrupted equally under
unilateral and bilateral anesthetization.
The findings of Larsson and Thilander (1964) prove
quite provocative. These researchers evaluated the effects
of certain "distracting" stimuli including stroboscopic light
flicker, sound stimulis (clicks), stimulation of the right
median nerve, painful pressure applied on the joint, and pain¬
ful pressure applied anterior to the joint on subjects' abi¬
lity to replicate arbitrary jaw position (Thilander, 1961).
The subjects performed significantly poorer than normal un¬
der all conditions of "distracting" stimuli except when
painful pressure was applied to the joint. Performance under
this condition did not vary from normal. Further investiga¬
tion of this phenomena revealed that a more moderate, pain¬
less pressure could normalize the disruptive effects of any
of the "distracting" stimuli and even more remarkably, a

28
painless pressure could normalize the disruptive effects
of unilateral anesthetization of the TMJ capsule when the
pressure was administered to the contralateral joint capsule
The authors theorized that the normalizing effect was the re¬
sult of activation of nervous elements in the richly inner¬
vated lateral aspect of the capsule. They also explained
that there may be alteration in the tension of the capsule
requiring less movement than normal to discharge receptors.
Thus, positional changes could be perceived more readily.
Ransjo and Thilander (1963) demonstrated that the func¬
tion of the TMJ receptors is impaired in TMJ disorders
ascribed to malocclusion, but not dysfunctions of myogenic
origin. Storey (1968) interpreted these results as indi¬
cating that the masticatory muscles are not involved in per¬
ception of mandibular position. Ransjo and Thilander (1963)
reported also that in cases of unilateral TMJ dysfunction
again a painless pressure applied to either the intact joint
or both joints would normalize the perception of mandibular
position. The impaired perception of mandibular position in
the malocclusion group could also be normalized by adjusting
and correcting the malocclusion.
Finally, Posselt and Thilander (1965) studied the role
of the TMJ receptors in controlling border movements (extreme
positions) of the mandible. They reported significant in¬
creases in maximum vertical jaw opening under conditions of
unilateral and bilateral anesthestization of the TMJ capsules
They concluded that the TMJ ligaments participate not only in

29
mediating the perception of position, but also appear to act
as a protective mechanism during extreme open positions of
the mandible.
The evidence to date suggests that a subject's ability
to perceive and/or to discriminate between different mandi¬
bular positions, as measured by tasks of interdental thickness
discrimination, is independent of the presence of natural
or artificial dentition. In addition, this ability also
appears to be independent of the sensory integrity of the an¬
tagonistic teeth. However, there is strong evidence that the
nerve endings in the TMJ are responsible, at least in part,
for mediating perception of mandibular position.
More recently, Si i rila and Laine (1972) presented the
results of a study designed to study the effect of anesthesia
of the TMJ capsule on subjects' ability to judge between dif¬
ferences in mouth opening. These researchers used a modi¬
fied caliper to establish the difference necessary to descrim-
inate mouth openings from a series of standard openings.
Subjects' performance under bilateral intracapsular TMJ
anesthesia was equivalent to their performance for the normal
condition. They concluded that different sensory mechanisms
might be involved in replicating a mouth opening (Thilander,
1961) and their task of size discrimination. However,
Siirila and Laine's (1972) test protocol allowed subjects
to tap their teeth against the test instrument. Tapping
very likely activated sensory endings in the periodontal
ligament and receptors in the TMJ that respond to movement.

30
Williams and LaPointe (1974), reported earlier, suggested that
smaller values of mouth opening may be discriminated when TMJ
movement is allowed.
Deglutition - mastication
The process of deglutition and mastication have been
described narratively by Fletcher (1970 and 1971). Fletcher
(1970) described the role of the mandible in a mature
swallow as providing a stable base from which the oral
strutures function as they collect a bolus and force it
posteriorly. A graphic description of mandibular movement
during mastication has been provided recently by Gibbs et al.
(1971) and Gibbs and Messerman (1972). Using the Case Gnathic
Replicator (Gibbs et al ., 1 966), they were able to record
graphically mandibular motion in three planes of movement.
Many of their comparisons of the mandibular masticatory
process were relative to mandibular movement for speech
function. For example, they found that the maximum vertical
opening for chewing was typically two to four times more than
the vertical opening for speech. The amount of vertical
opening during speech was relatively equal between subjects
while it varied considerably for chewing. Speech function
involved little lateral motion of the mandible whereas there
was a great deal of lateral movement during chewing. Hori¬
zontal or anterior-posterior movement of the mandible appeared
equal for both processes, however, it was proportionately
greater in relationship to vertical movement for speech. There
was asymetrical motion of the condyles during mastication.

31
The working condyle, on the side with the food, reached the
maximum opening first. The mandible stopped movement during
chewing for a brief time at its closed stage. Condylar move¬
ment was prominent in masticatory function, but not for speech.
Finally, the average maximum velocities for chewing were
considerably greater than for speech (6.05 in./sec. and 1.65
in./sec. respectively). Gibbs and Messerman ( 1 972) concluded
that much important information concerning mandibular movement
for speech could be obtained from measuring the vertical and
horizontal motion exclusively.
Interest in mandibular movement for deglutition and the
masticatory process necessarily implies interest in the systems
neurocontrol mechanism. Ingervall et al. (1971) examined the
occlusal positions of the mandible and the movements of the
hyoid bone with and without anesthesia of the TMJ capsules.
These researchers reported that dental contact was common
during swallowing and could find no differences in positions
between swallowing prior to or during anesthetization. The
hyoid bone movement patterns were also independent of the
anesthesia condition.
Ingervall et al. (1972) utilized the films collected
earlier (Ingervall et al â– , 1971) and evaluated the influence
of the receptors in the TMJ capsules on the duration of
swallowing and movements of the hyoid bone. They reported
that bilateral anesthetization of the TMJ capsule had no effect
on the duration of the movement of the hyoid bone. This is not

32
too surprising since the swallow patterns include dental
occlusion and thus provided added feedback from the perio¬
dontal ligament. In addition, there is no reason to suspect
that the temporomandibular articular receptors provide any
feedback which would influence the oral structures involved
in swallowing as they appear to be more active in conscious
positioning of the mandible and the mandible is already po¬
sitioned at the iniation of the swallow sequence.
Several other researchers have explored the nature of
the control of the mandible for dynamic masticatory function
either directly or indirectly. Shepherd (1960) reported that
the total movement of the mandible decreased with age, use
of dentures, and introvert personality type. Denture wearers
demonstrated similar masticatory patterns with and without
their dentures, however, as might be expected, the amount of
vertical movement was much greater without dentures. The
masticatory pattern was also unchanged prior to and after
complete teeth extraction. However, abnormal masticatory
patterns were evident in individuals who demonstrated exces¬
sive occlusal wear and who had pain, clicking, or other symp¬
toms of TMJ dysfunction. The author reported that in no case
where the TMJ was showing abnormal symptoms was the associated
masticatory cycle considered to be normal. In many cases,
marked irregularities occured in the patterns with a lack of
smoothness in individual cycles and sometimes there was a
complete lack of rythm from cycle to cycle.
These findings were supported by Atkinson and Shepherd
(1961). In one patient whose TMJ dysfunction was diagnosed

33
as resulting from malocclusion, the malocclusion was adjusted
with an appliance. The resulting masticatory movement was
found to be much smoother.
In a study reported by Schaerer et al. (1 966), anesthesia
of the TMJ capsules and periodontal ligament did not effect
mandibular movements, muscle activity, or contact between teeth
during chewing. Thus, it appears that mandibular movement and
positioning during the processes of deglutition and mastication
in normal individuals is not disrupted by anesthetizing the
TMJ. However, abnormal masticatory patterns have been observed
in individuals who have demonstrated excessive occlusal wear
and have had pain, clicking, or other symtoms of TMJ dysfunc¬
tion. This might suggest that long standing disruption of
TMJ function is necessary before there is observable altera¬
tion in the masticatory stroke.
Speech function
The initial interest in mandibular movement and position
during speech appears to have been generated by researchers in
the field of prosthetic dentistry. Simple phonetic tests, such
as counting from one to ten or repeating /s/ loaded words,
hve been used to establish "closest speaking space" or closest
interdental space in the construction of clinically accepted
dentures (Geissler, 1971 and Gillings, 1973).
Recently, speech researchers have begun to measure
mandibular position for speech function while systematically
varying phonetic context. The results of the research from

34
these two areas is in close agreement and can be summarized
and discussed together. Another current investigation of
speech and masticatory function (Gibbs and Messerman, 1972)
has been discussed earlier and will not be included here.
There seems to be a general agreement among researchers
that jaw position is lower for vowel sounds (/o>/ ,/:>/), diph¬
thongs (/aI/), and back consonant (/k/,/g/) production and is
more elevated for high vowels (/i/,/u/) and front consonant
(/p/,/s/) production. The mandible has been observed to dis¬
place posteriorly as it displaces inferiorly. Kent and Moll
(1972) and Owens (1973) have explained that this is due to
the hinge-type movements of the condyle for the mandible's
speech movements. It is also recognized that adjacent pho¬
nemes may cause mandibular position to vary slightly for any
one phoneme. Geissler (1971) has demonstrated further that
mandibular movement may vary with speaking rate, becoming
less as speaking rate increases. Geissler (1971) and Gillings
(1973) have observed also that while mandibular position for
closed sounds tends to be fairly consistent from individual
to individual, the position of the mandible varies from in¬
dividual to individual for open sounds. Although there is
obviously room for continued research in this area, it is
apparent that specific mandibular positions are responsible
for specific phonetic productions.
Other areas of mandibular dynamics are also currently
under investigation. New research is providing information
that is beginning to explain the complex interplay between
the dynamic mandible and other articulators including the lips

35
and the tongue. It is now obvious that the tongue does not
move in complete harmony with the mandible (Kent, 1972).
Kent (1972), who studied the relationship of tongue body and
mandibular movement during speech, concluded that the overall
displacements of the tongue body and jaw vary with phonetic
context. He also identified a "trading relationship" between
the tongue and the mandible; the smaller the amount of jaw
movement, the greater must be the extent of tongue motion.
Sussman et al. (1973) reported that although the jaw
and the lower lip are mechanically linked and constrained by
each other, they also act as independent articulators, each
reflecting their own specific movement characteristics. He
also reported that the less the jaw contributes to the forma¬
tion of a bilabial stop, the higher the elevation of the lower
lip.
This independence in movement between jaw and tongue
and jaw and lip might be interpreted as evidence for separate,
yet interconnecting feedback systems where one system is
responsible for monitoring the other and compensating for it.
Further research of mandibular and tongue body dynamics
reveals similarities in the relationship of movement velocity
to displacement. That is, the greater the displacement of the
structure during speech, the greater the velocity of movement
(Abbs et alâ– , 1 972; Sussman et al â–  , 1 973; and Kent and Moll,
1972).
There is research in the literature that assists in
understanding the complex interplay between the mandible and

36
the other oral structures during speech. Hansen (1952)
studied speech intelligibility using single words under
varying conditions of jaw restriction from full restriction
to no restriction. He found no differences in intelligi¬
bility among any of the conditions. This researcher noted,
however, that a speech sample simulating connected speech
might yield different results. These findings are in agree¬
ment with those of Kent (1972), who reported the indepen¬
dence of tongue and jaw dynamics and the apparent compensa¬
tory action between the two.
Weiss (1969a) disrupted lingual and palatal taction
in eleven year olds and reported that this disruption does
not significantly effect the acoustic parameters of articu¬
lation. Weiss (1969b) evaluated the lingual-palatal and
mandibular placement of the subjects of his earlier study.
He discovered that the tongue tip placement for some phonetic
productions were disrupted, although there was no signifi¬
cant overall disruption. However, he did report that there
was greater mandibular displacement after anesthesia for the
phonemes III and , two phonemes that seem to involve less
tactile feedback than most. Following anesthetization, there
was also greater variation in the physiologic rest position
of the mandible. Weiss (1969b) questioned whether disrupted
taction of one structure in the articulatory system affects
the function of another in the same system.
Sussman and Smith (1971) monitored and recorded jaw
movements under varying degrees of DAF. They reported no

37
overall disruptive effects of DAF on jaw positioning nor on
the duration of the velocity of jaw movement. However, they
did find isolated instances of disruption. Although not
statistically significant, there seemed to be a trend for the
jaw to overshoot its position for some vowels under the 0.3
second delay condition. They also reported a significant in¬
crease in the length of jaw activity for the 0.1 second delay
condition. These results offer some evidence that auditory
feedback may be important in controlling mandibular position.
Research on mandibular function for speech processes
has demonstrated the vertical and horizontal positioning is
dependent on the phonemic makeup of the speech sample.
Current research has provided information of the independent,
yet complimentary actions of the mandible and the tongue
during articulation. Investigators who have disrupted lingual
tactile and auditory feedback during speech have reported only
minimal and inconsistent alterations of mandibular position.

CHAPTER TWO
STATEMENT OF PROBLEM
The literature reviewed in CHAPTER ONE suggests that
experimental anesthetization of the oral structures results
in quantifiable alterations in subjects' performance on
oral-sensory-perceptual tasks as well as alteration of cer¬
tain characteristics of speech production. The literature
reviewed has revealed also that mandibular position is spe¬
cific for certain phonetic productions. In addition, these
studies reveal that the sensory mechanism within the TMJ
apparently controls, to some degree, the movement and posi¬
tioning of the mandible. Moreover, it would appear that
measurement strategies, such as duplicating an interdental
space (Thilander, 1961) or interdental thickness discrimin¬
ation (Williams and LaPointe, 1972 and Williams et al. ,
1974) might be used in determining as index of sensory in¬
tegrity of the TMJ. The literature reviewed has demonstrated
further that the effect of anesthetizing one TMJ can be nor¬
malized by a painless pressure applied to the contralateral
capsule (Larsson and Thilander, 1964).
If anesthetization of the TMJ causes impairment in the
regulation and control of mandibular position, and if fine
sensory motor coordination of jaw placement and movement is,
in fact, critical for the production of normal speech sounds,
38

39
it seems reasonable to suggest that disruption of the TMJ
sensory system would have a demonstrable effect on the overall
articulatory pattern of the mandible for speech production.
It might be suggested also then that the application of
pressure to the unanesthetized TMO might be expected to have
a normalizing effect on mandibular patterns of movement and
positions for speech. However, a review of literature has
failed to identify any investigation directly concerned with
the role of the TMJ sensory mechanism as related to the
regulation and control of mandibular movement and positioning
for speech sound production.
Statement of Purpose
Therefore, the purpose of this study is basically two¬
fold: 1) to determine what effects occur with unilateral
anesthetization of the TMJ relative to the positioning and
movement patterns of the mandible during selected perceptual
tasks, nonspeech oral movements, and a selected speech sample
and 2) to determine what effects occur with a subsequent
administration of a painless pressure to the TMJ capsule
opposite the one anesthetized on the positioning and movement
patterns of the mandible during selected perceptual tasks,
nonspeech oral movements, and a selected speech sample.
Specific Objectives
A series of tasks was devised in an attempt to measure
the effect of the anesthesia and pressure on the positioning

40
of the mandible. All of the tasks were performed under the
two experimental conditions and under a normal, control
condition with no anesthesia and no pressure. The three
categories of tasks included: 1) four perceptual measures
of mandibular position discrimination and one perceptual
measure of interdental weight discrimination, 2) two tasks
requiring nonspeech oral movements, and 3) nine tasks
requiring speech sound production. Thus, there was a total
of sixteen separate tasks.
The specific objectives of the study were:
1) to compare subjects' performance on each of the
five perceptual tasks under the two experimental conditions
and the one control condition,
2) to compare subjects' performance on each of the
two tasks requiring nonspeech oral movements under the two
experimental conditions and one control condition, and
3) to compare subjects' performance on each of the
three tasks requiring speech sound production under the two
experimental condition and one control condition.

CHAPTER THREE
METHODS AND PROCEDURES
Subject Selection
Four young adult males served as subjects. Their ages
range from 22 years, 4 months to 29 years, 4 months with a
mean age of 25 years, 11 months. The individuals who served
as subjects possessed all of their natural central incisors,
had an Angle Class ONE occlusion with a normal bite. None of
the subjects complained of any current or past history of TMJ
dysfunction. All subjects were monolingual speakers of the
General American Dialect and had no articulation or voice
disorders.
Experimental Tasks
Perceptual Measures
The perceptual measures utilized in this study were de¬
signed to assess subjects' abilities to discriminate between
differences in mandibular positions and to discriminate be¬
tween differences in weights placed between the maxillary and
mandibular incisors. The first perceptual measure required
each subject to duplicate an arbitrary interdental space.
This task was included as an attempt to replicate and verify
Thilander's initial research in the area of TMJ anesthetiza¬
tion.
41

42
Three of the perceptual tasks were designed to assess
subjects' ability to discriminate between pairs of mandibular
positions in the three planes of space. These tasks include
discrimination of pairs of positions in the vertical dimension
(interdental thickness discrimination), in the lateral dimen¬
sion (discrimination of lateral mandibular positions), and in
the anterior-posterior dimension (discrimination of anterior-
posterior mandibular positions).
The fifth and final perceptual task required subjects
to make judgements between pairs of weighted capsules placed
between the maxillary and mandibular incisors. This task was
included in an attempt to either implicate or rule out the
sensory mechanism of the TMJ as having a role in interdental
weight discrimination. Tasks were presented in a random order
Duplication of an interdental space
This task required each subject to reproduce an arbi¬
trarily determined, comfortable open mouth position somewhere
between the closed or physiologic rest position and a maximum
open mouth position (Thilander, 1961). The amount of mouth
opening was determined by measuring the distance between the
upper and lower central incisors with a plastic ruler.
Measurements were taken to the nearest millimeter. The ruler
was shaped so that one end would fit over the incisal edge of
the lower incisors to insure standard measurement conditions.
Each subject was instructed to remember the initial mouth
or jaw open position and then to attempt to replicate this
same position ten times in close

43
succession. The distance between the upper and lower central
incisors was measured and recorded by the examiner for each
of the ten subsequent trials. The subject was not informed
as to the accuracy of his responses.
Interdental thickness discrimination
This task required each subject to make judgements
concerning the thickness of blocks placed in pairs, one at
a time, between the maxillary and mandibular central incisors.
The instrumentation used in this task, which was developed
by Williams and LaPointe (1972), is illustrated in Figure
8 and consists of 21 acrylic blocks, each 4.5 cm long by
1.5 cm wide. The thickness of the blocks varies in 1 mm
increments and ranges from 10 to 25 mm. In performing this
task, each subject was asked to judge whether the second
block of each pair was "the same," "thicker," or "thinner"
than the first block of the pair. The first block in
each pair presentation was considered the "standard" and was
always 10 mm thick. The second block presented in each pair
was a different thickness. A modified "method of limits"
procedure, with two ascending runs, was used to arrive at
each subject's difference limen. A "run" was defined as
the presentation to the subject of as many different pairs
of blocks as necessary until two consecutive correct judge¬
ments were made.
Discrimination of lateral mandibular positioning
Each subject's ability to discriminate differences in

Figure 8
Acrylic Blocks for Assessing
Interdental Thickness Discrimination

Figure 9
Devices for Assessing Anterior-Posterior and
Lateral Mandibular Placement Discrimination

46
mandibular position lateral to a midline position was
assessed using an instrument designed and developed by
Williams and LaPointe (1973). This instrument is illustrated
in Figure 9. The device consists of two interlocked, sliding
plates that are adjustable in one-half millimeter increments
by means of a thumb screw which allows for controlling the
position of one plate in relation to the other. The v-shaped
wedge on the upper plate was positioned in the space between
the two maxillary incisors. The subject then moved his jaw
about until the lower plate seated between the space of the
two mandibular incisors. This task required the subject to
make judgements concerning the lateral position of his lower
jaw as determined by the positions of the lower wedge, which
were presented to him, in pairs, one at a time. Each subject
was asked to judge whether the second position was "the same,"
"to the left," or "to the right" of the first position. The
first position, considered the "standard," was always that
position where upper and lower wedges were in a vertical line.
The second position in each pair was a different position
either to the left or to the right of midline. Again, a
modified "method of limits" procedure, with two ascending runs,
was used to arrive at each subject's difference limen in a left
or right direction. As in the interdental thickness task, a
"run" was defined as the presentation of as many different
pairs of wedge settings as necessary until two consecutive
judgements were made.

47
Discrimination of anterior-posterior mandibular positions
Each subject's ability to discriminate between mandibular
postions anterior to a position in which the maxillary and the
mandibular incisors are in a vertical line was assessed
utilizing the same instrument which was used in assessing
lateral discrimination ability. For the anterior-posterior
task, however, the inverted v-shaped wedge on the upper plate
(shown at left of instrument in Figure 9) was placed over
the maxillary incisors seated in the wedge on the lower plate.
This task required the subject to make judgements concerning
the anterior position of his jaw as determined by the positions
of the lower wedge which were presented to him in pairs, one at
a time. Each subject was asked to judge whether the second
position of each pair was "the same," "forward," or "backward”
compared to the first position. The first position, again
considered the "standard," was always that position where the
upper and lower wedges were in a vertical line. The second
position of each pair was a different position anterior to the
first. The same modified "method of limits" procedure, with
ascending runs, was used to determine each suject's threshold
of detecting differences in jaw positions in the anterior
direction. A "run" was defined as it had been for the pre¬
ceding tasks.
Interdental weight discrimination
This task was used to assess each subject's ability to
discriminate between pairs of weighted capsules. The task
utilized the instrumentation shown in Figure 10. The

Figure 10
Weighted Acrylic Capsules for Assessing
Interdental Weight Discrimination

49
instrumentation was developed by Williams and LaPointe (1972)
and uses 21 capsules ranging in weight from 5 to 25 grams.
This task required each subject to make judgements between
pairs of weighted capsules which were presented, one at a time
between the maxillary and the mandibular central incisors.
Each subject was asked to judge whether the second of each
pair of capsules was "the same," "heavier," or "lighter" than
the first capsule. The first capsule was always the "standard
weight of 5 grams. The second capsule of each pair was always
heavier than the first. A modified "method of limits," with
two ascending runs, was used to arrive at each subject's
difference limen. A "run" was defined as for the previous
perceptual tasks.
Nonspeech Oral Movements
Tasks of nonspeech oral movement were included in the
study since evidence suggests that the neurological process
governing speech and nonspeech oral movements are dissimilar.
Hixon and Hardy (1964) suggested that speech movements may be
the result of automatic, programmed motor patterns, while less
practiced nonspeech oral movements, such as repetitive raising
the tongue to and dropping it from the alveolar ridge, would
require voluntary, concentrated motor movements.
Two nonspeech oral movements were used on this study to
examine the role of the sensory mechanism of the TMJ for
regulating mandibular movement and positioning for nonspeech
activities. These tasks required each subject to: 1) elevate
the tongue tip up against the alveolar ridge and to drop it

50
from this contact and 2) elevate the dorsum of the tongue up
against the roof of the mouth and drop it from this contact.
Each of these two tasks were performed three times by each
subject.
Speech Sample
A primary purpose of the study was assessment of the
effects of the experimental conditions on mandibular posi¬
tion during speech production. A speech sample was devel¬
oped which provided varied amounts of 1ingual-palatal con¬
tact, required a wide range of mandibular positioning, and
contained a wide range of speech sounds. The speech sample
required each subject to produce a series of diphthongs, a
series of vowel-consonant-vowel (VCV) combinations, as well
as a sample of connected speech.
Vowel-consonant-vowel s : / i s i / , fosa./ , /iki/, and /a-ko./
The VCV combinations were formed using consonants and
vowels that have been reported to require a wide range of
mandibular placements. Kent and Moll (1972) and Owens (1973)
have shown that front consonants, such as the /s/, and high
vowels, such as /i/, are produced with a more elevated man¬
dibular placement than are the back consonants, such as /k/
and the low vowels, such as /a/. Therefore, the following
VCV combinations were developed: / i s i / , /asa./, /iki/, and
/aka./. Each of the VCV combinations were spoken three times
by each subject for three of the conditions. Subjects were
instructed to put the same stress on the second vowel as
they did on the first one.

51
Diphthongs: /al/, /el/, /aU/, /3l/
A diphthong has been defined by Wise (1957) as two
vowels pronounced in a quick, unbroken succession within a
syllable, and connected by a gliding series of unrelated
sounds. Four diphthongs were included in the speech sample
because of their unique arrangement consisting of a low or
mid vowel and a high vowel. Production of these diphthongs
requires considerable mandibular and lingual movement with
minimal 1ingual-palatal contact. The diphthongs used in this
study were: /al/, as in the word "high," /el/, as in the word
"hay," /OI/, as in the word "hoist," and /aU/, as in the word
"how.” As for production of the VCV combinations, each of the
diphthongs were spoken three times by each subject for each of
the three conditions.
Connected speech
The sentence "In the evening Connie watches TV with me."
was selected as a representative sample of ongoing speech. It
contains a distribution of front and back consonants, such as
/t/ and /k/, as well as vowels which represent the extremes of
the vowel triangle, such as /i/ and /a-/. Each subject was
instructed to repeat the sentence in their usual speaking
manner relative to such factors as intensity, duration, and
inflectional patterns.
Experimental Procedures
Two experimental conditions were developed for this
study. The experimental conditions were: 1) unilateral anes¬
thetization of the right auriculotemporal nerve (innervating
the right TMJ)

52
and 2) anesthetization of the right auriculotemporal nerve
with a painless pressure administered to the contralateral
TMJ capsule. All of the experimental tasks outlined were
performed by each subject under each of the experimental
conditions and under a normal condition where the subject
received neither anesthesia nor pressure stimulus.
Anesthetization
Anesthetization of the auriculotemporal nerve was
performed and observed by Parker E. Mahan, D.D.S., College
of Dentistry, University of Florida. A 2% xylocaine solution,
with a vaso-constrictor, was injected into the nerve as it
ascends near the posterior border of the mandible. Approx¬
imately 0.8 cc of xylocaine was used for each anesthetization.
The anesthetized state was maintained for approximately
three to four hours as evidenced by subject report. All
subjects received the anesthesia on their right side.
Pressure
The second experimental condition involved applying
pressure to the left TMJ capsule while the right TMJ was
anesthetized. The pressure device, ill ustra ted in Figure 11,
incorporates a calibrated, spring-loaded disc 2.5 cm in
diameter. The design allows for monitoring the amount of
force that the disc exerts against the TMJ capsule. The
amount of pressure, acknowledged as less than painful
by each subject, varied from 1.0 to 2.0 pounds. The mean

Figure 11
Cephalostat and Pressure Device

54
amount of pressure used was 1.8 pounds.
The pressure device was attached to a cephalostat,
which is also illustrated in Figure 11. The cephalostat
was designed to fit around the subject's head, in a halo
fashion, with four points of contact for stabilization, two
anteriorly and two posteriorly. This desiqn prevented any
interference with the movement of the muscles of mastica¬
tion. Both the cephalostat and the pressure device were
desiqned by the author and were constructed in the Bioinstru¬
ment Shop at Shands Teaching Hospital, University of Florida.
Filming Procedures
The nonspeech oral movements and speech tasks were re¬
corded cinef1uoroscopically. A 16 mm Auricon Cine II Voice
camera mounted on a Picker fluoroscope, with a five inch
image intensifier, was used to obtain the cinefluorographic
films of the speech structures during the production of the
nonspeech oral movements and during production of the speech
sample. Eastman Kodak Double X film (type 7222) with a mag¬
netic sound strip was used. The filming speed was 24 frames
per second. The film was processed in a Smith-Picker auto¬
matic processor. The radiographic and the film processing
equipment are located in Shands Teaching Hospital, University
of Florida.
Each subject was filmed in a upright sitting position
with his head positioned and stabilized in the cephalostat.
A radiopaque, stainless steel ruler, with holes drilled into

55
it at centimeter intervals, was inserted in the subject's
mouth at the initiation of filming. It was, therefore, pos¬
sible to project the filmed image at some known magnification
relative to life size.
Procedures For Film Data Collection
Measuring Apparatus
A Lafayette Analyzer 16 mm Projector was used to analyze
the cinefluorographic films. The Lafayette Projector is cap¬
able of frame bv frame projection or continuous projection at
variable speeds. The image of the subject and the ruler was
projected one and one half times larger than life size by ad¬
justing the position of the perpendicularly mounted tracing
board relative to the projector. It was necessary to project
the image- to this size because of the limitation of the pro¬
jector to focus the image any smaller. All of the measure¬
ments were corrected to life size following compilation of
the data.
Construction of Template
Prior to measurement, a template was constructed from
the projected image of the initial frame depicting the mid¬
line structures. The midline structures included the hard
palate from the anterior nasal spine to the posterior nasal
spine, the upper central incisors, and the alveolar ridge.
These structures were used for constucting lines of reference
as well as for adjusting the template to the frame to be mea¬
sured in order to insure accuracy of measurement.

56
Planes of Reference
Three lines of reference were constructed on the template
for measurement of the vertical and horizontal positions of
the mandible. Figure 12 illustrates these lines of reference.
Line PP. This line defines the palatal plane which is a
standard reference line in cephalometric studies. This line
is defined as a line which passes through the midpoint of the
anterior nasal spine and the midpoint of the posterior nasal
spine. This line was chosen because it approximates the
horizontal plane and provides a reference line for measuring
the vertical position of the mandible.
Line AB. This line represents a plane which is parallel
to the palatal plane and is tangent to the most inferior point
of the central maxillary incisor. This line also approximates
a horizontal plane and allows for easier measuring of vertical
jaw positions than would making measurements from the central
mandibular incisor to the palatal plane. The vertical posi¬
tion of the mandible was recorded relative to this line.
Line CD. This line represents a plane which is perpen¬
dicular to the palatal plane. This line passes through the
most inferior midpoint of the upper central incisor. This line
approximates a vertical plane and serves as the reference for
measuring the horizontal positioning of the mandible.
Definition of Measurements
The vertical and horizontal positions of the mandible
were measured relative to the planes of reference defined

57
2. Measurement of vertical mandibular displacement noted
in an upward or negative (-) direction.
3. Measurement of horizontal mandibular displacement noted
in a backward or positive (+) direction.
4. Measurement of horizontal mandibular displacement noted
in a forward or negative (-) direction.
Figure 12
Defined Measurements of Mandibular Displacement
and Associated Positive and Negative Values

58
above and illustrated in Figure 12. The following discussion
defines the vertical and horizontal measurements of mandibular
displacement.
Measurement of vertical mandibular position. Measurement
of the vertical position of the mandible was defined as the
perpendicular distance between the seperior tip of the mandi¬
bular central incisor and line AB. A positive value was
assigned when the tip of the lower central incisor was below
AB and a negative value was recorded when the tip of the
incisor was above line AB.
Measurement of horizontal mandibular position. The
horizontal position of the mandible was defined as the perpen¬
dicular distance between the tip of the mandibular incisor
and line CD. Positive values were assigned when the position
of the tip of incisor was posterior to the line CD. Negative
values were assigned when the tip of the incisor was observed
to be in front of line CD.
Identification of Frames Measured for the Speech and Nonspeech
Tasks
The initial and the final frames of each of the nonspeech
and the speech tasks were located and marked. The segment of
film portraying the production of each of the tasks was then
numbered consecutively, frame by frame, for ease of identifi¬
cation.
Nonspeech tasks
Tongue tip to alveolar ridge. The frame identified as the
initiation of this nonspeech task of elevating the tongue tip

59
to the alveolar ridge was defined as that frame showing the
tongue first making contact with the alveolar ridge. The
final frame for that task sequence was identified as that frame
showing the tongue in its lowest position just prior to its
elevation for the beginning of the next trial. In addition,
a third frame was identified in which the tongue was observed
to be releasing contact from the alveolar ridge. It was,
therefore, possible to define the position of the mandible at
the beginning and at the end of the three trials for this
task, as well as the range of mandibular movement throughout
each trial. The length of time (in number of frames) for the
completion of each trial and the length of time of lingual
palatal contact was defined also.
Tongue dorsum to palate. The frame identified as the ini¬
tiation of this nonspeech act was defined as that frame showing
the tongue contacting the palate approximately at the posterior
nasal spine. The frame showing the tongue in its lowest posi¬
tion just prior to elevation for the beginning of the following
trial was defined as the final frame in each trial. A third
frame showing the tongue releasing contact from the palate
was also identified. Again, it was possible to define the
position of the mandible at the initiation and completion of
each trial for this task and the range of mandibular movement
through each trial. The length of time for the completion of
each trial and the amount of time during which the tongue
was in contact with the palate was recorded also.

60
Vowel-consonant-vowel s : /isi/, /asa./, / i k i / , and /aka,/
Those frames identified as the beginning and the end of
each VCV sequence were defined in terms of optimal lingual
placement for the production of the two vowels /i/ and /a/.
The frame showing the vowel /i/ as it occurred in the
initial position of the VCV sequence was defined as that frame
picturing the tongue in its highest position prior to its
movement for the production of the following consonant. The
frame showing the vowel /a./ as it occurred in the initial
position was defined as that frame showing the lowest tongue
position prior to its movement for the production of the
following consonant.
The frame showing the vowel /i/ as it occurred in the
final position of the VCV sequence, was defined as that frame
showing the tongue in its highest position prior to its move¬
ment to a rest position. The frame showing the vowel /a/, as
it occurred in the final position of the VCV sequence, was
defined as that frame showing the tongue in its lowest position
prior to its movement to a rest position.
In addition to the initial and the final frames of each
trial, those frames depicting the lingual palatal contact
required for consonant production were identified. Thus, it
was possible to define the vertical and the horizontal position
of the mandible at start and finish of each trial as well as
during consonant production. These measurements also provided
the range of mandibular motion throughout each trial. The
length of time for the completion of each trial and the amount
of time required for the production of the consonants and the
vowels were recorded also.

61
Diphthongs: /al/, /el/, /aU/, and /jl/
The initial and the final frames representing the pro-
duction of each of the diphthongs were identified as those
frames showing optimal tongue or lip placement for the produc¬
tion of the respective vowels.
The frames identified as the production of the vowels
/a/, /e/, and /o/ as they occur in the initial positions of
the diphthongs /al/, /el/, and /jl/ respectively were defined
as those frames showing the tongue in its 1owest position
prior to elevation for the production of the second vowel in
the diphthong. The frame identified as the production of the
vowel /a/ in the initial position of the diphthong /all/ was
defined as that frame showing the lip in its lowest position
prior to its elevation for rounding in the production of the
second vowel in the diphthong.
The frames identified as the production of the vowel
/I/ as it occurs in the final position of the diphthongs /al/,
/el/, and /jI/ were defined as those frames showing the
tongue in its highest position prior to its lowering for the
initiation of the next trial. The frame identified as show¬
ing the production of the vowel /U/ as it occurs in the final
position of the diphthong /all/ was defined as the frame show¬
ing the lower lip in its highest position prior to its lowering
for the beginning of the next trial.
It was possible, therefore, to define the vertical and
horizontal position of the mandible at the beginning and at
the end of the production of each trial as well as the range

62
of mandibular motion through each trial. The length of time
required to complete each trial was recorded also.
Sentence
Seventeen frames depicting the production of seventeen
speech phonemes were selected from the sentence, "In the
evening Connie watches TV with me." The selected phonemes are
represented by the underlined graphemes in the sentence below.
IN THE EVENING CONNIE WATCHES TEE
1 23 4567 8 9 10 1112
V E E W I TJH M E .
13~T4 15 16 17
The definitions for identifying these phonemes within the
sentence from cinef1uorographic recordings have been described
in detail by Owens (1973) and have been duplicated here for
convenience.
1. The /5/ of “the" was defined as the 1ingual-dental contact
immediately following the 1 ingua1-alveolar contact required
for the production of the phoneme /n/ of "in/1.
2. The /i/ of "evening" was defined as the highest point of
lingual elevation preceding the labial-dental contact re¬
quired for the production of the phoneme /v/ of "evening".
3. The /v/ of "evening" was defined as the 1abi a 1-dental
contact necessary for its production.
4. The /j / of "evenimj/1 was defined as the part of lingual-
velar contact between the back of the tongue and the velum
while the velum was down.
5. The /k/ of "Connie" was defined by the 1 ingua1-velar contact
required for its production while the velum was

63
closing off the velopharyngeal port.
6. The /a/ of "Connie" was defined as the lowest and most
posterior point of lingual movement preceding the lingual-
alveolar contact required for the production of the phoneme
/n/ of “Connie" .
7. The /n/ of "Con_nie" was defined as the 1 i ngual-al veol ar
contact required for its production.
8. The /w/ of "watches" was defined by the maximum forward
movement of the lips required for its production,
9. The A>V of "watches" was defined as the lowest and most
posterior point of lingual movement preceding the lingual
alveolar contact required for the production of the / tf /
of the word "watches".
10. The / ff / of "watches" was defined as the 1 i ngual-al veol ar
(sometimes 1ingual-pa 1 a tal ) contact required for its pro¬
duction while the teeth were closed and the lips pro¬
truded slightly.
11. The /t/ of "TV" was defined as the lingual-alveolar con¬
tact required for its production.
12. The first /i/ of "Tee Vee" was defined as the highest point
of ligual movement preceding the 1abial-dental contact re¬
quired for the production of the phoneme /v/ of "TV_".
13. The /v/ of "TV/1 was defined as the labial-dental contact
requiredforitsproduction.
14. The second /i/ of "Tee Vee/' was defined as the highest
point of lingual elevation preceding the forward move¬
ment of the lips required for the production of the
phoneme /w/ of "with".

64
15. The IQI of "with" was defined as the 1ingual-dental
contact required for its production.
16. The /m/ of "me" was defined as the bilabial contact re¬
quired for its production.
17. The /i/ of "mis" was defined as the highest point of
lingual elevation following the bilabial contact required
for the production of the phoneme /m/ of "me".
Reí iabi1ity
Since the author made all measurements, only inter¬
measurer reliability was assessed. The vertical and horizontal
measurements were remeasured for forty-five frames. The cor¬
relation between the initial and the second measurements was
calculated. A correlation coefficient of .99 was obtained for
the forty-five vertical measurements and a coefficient of .97
was obtained for the forty-five horizontal measurements. These
correlation coefficients are considered to be within acceptable
limits.

CHAPTER FOUR
RESULTS
The results of this study will be presented relative to
1) descriptive analysis of the data and 2) statistical analysis
of differences between the experimental and control conditions.
Descriptive analysis was completed for the five perceptual mea¬
sures and the connected speech passage. Measurements of cen¬
tral tendency and the dispersion of performance on each of the
test measures accompanies a narrative description of the re¬
sults. Statistical analysis was completed for ten test mea¬
sures including the two nonspeech tasks, the four tasks of
diphthong production, and the four tasks of vowel-consonant-
vowel production. The statistical analysis included an ana¬
lysis of repeated measures and the Newman-Keuls analysis. A
more detailed description of the statistical procedures fol¬
lows the presentation of the results for the perceptual mea¬
sures and sentence production.
Analysis of Perceptual Tasks and Connected Speech
Perceptual Measures
Duplication of interdental space
This task was included in an attempt to replicate a
portion of Thilander's (1961) study. Table 1 displays subject
65

66
Table 1
Individual Performance Scores and Group Means,
Ranges
Space
Subject
, and S.D.'s for Duplication
Task: Range of Jaw Position
Condition
of Interdental
for Ten Trials
Norma 1
Anesthetized Anesthetized and Pressure
A
3.0 mm
5.0 mm
3.0 mm
B
8.0
4.0
2.0
C
2.0
6.0
7.0
D
11.0
7.0
4.0
Means
6.00 mm
5.50 mm
4.00 mm
Standa rd
Deviation
4.24
1.29
2.16

67
performance during attempts to duplicate the standard position
ten times under the three conditions. Included in Table 1 are
means and standard deviations for the group of four subjects.
Anesthesia appeared not to make it more difficult for the
subjects to find the standard jaw opening; the mean for the
normal condition is 6.00 mm, while the mean for the anesthesia
condition is 5.50 mm. However, three subjects (A, B, and D)
of the four found it easier to duplicate the standard position
when a light pressure was applied to the left TMJ. This is
also reflected in a reduced mean performance score for the
pressure condition; X = 4.0 mm.
The mean difference in jaw position from the standard
position, as well as standard deviation, is presented in Table
2. The means obtained for each of the three conditions sug¬
gest that neither the anesthesia nor the anesthesia and pres¬
sure had an affect on the ability of the subjects to dupli¬
cate the standard. The means vary from a 3.25 mm for the
anesthesia and pressure condition to a 3.65 mm for the normal
condition.
Analysis of individual subject means presents somewhat
conflicting results. The ability of subjects A and C to du¬
plicate the standard was impaired somewhat by the anesthesia
condition. However, performance was improved by pressure to
the opposite TMJ only for subject A. Subject D's performance
also was improved by pressure, however, his performance under
anesthesia was better than under the control condition. More¬
over, the performance of subjects A and C was impaired by

68
Table 2
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for Duplication of Interdental
Space Task: Mean Difference of Jaw Position from
the Standard
Condition
Subject
Normal
Anesthetized
Anesthetized and Pressure
A
2.4 mm
4.4 mm
0.8 mm
B
4.1
2.7
3.6
C
1 .9
4.1
7.1
D
6.2
2.9
1 .5
Means
3.65 mm
3.52 mm
3.25 mm
Standard
Deviation
1.78
0.96
2.83

69
anesthesia compared to normal and the performance of A and D
was improved by pressure compared to anesthesia. Only subject
A fit the profile of performance presented by Thilander of
impaired performance under anesthesia condition and improved
under the pressure condition.
Interdental thickness discrimination
Individual subject performance scores for each of the
two runs are presented for the task of interdental thickness
discrimination in Table 3. The mean amount of thickness re¬
quired for two consecutive correct descriminations is greater
for anesthesia condition (1.75 mm) than for the normal con¬
dition (1.38 mm). Subjects required an average of 1.50 mm
difference under the pressure condition. This suggests that
some mild disruption occurred due to the anesthesia and some
recovery of discriminative abilities occurred with the ap¬
plication of pressure. Further analysis (Table 4) revealed
that 100% correct discrimination occurred under the normal
condition and pressure condition when the difference in
block size was 2 mm. However, 4 mm were required under the
anesthesia condition in order to obtain 100 % discrimination.
Discrimination of lateral mandibular position
Each subject's ability to discriminate between pairs of
lateral positions of the mandible was assessed to the left of
and to the right of midline. No difference in subjects' per¬
formance was observed between the control and anesthesia con¬
dition when ability on this task was tested to the left of

70
Table 3
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Thickness Discrimination
Condition
Sub.iect
Trial
Norma 1
Anesthetized
Anesthetized and Pressure
A
1)
1.0 mm
2.0 mm
1 .0 mm
2)
1.0
1 .0
1.0
B
1)
1 .0
1 .0
1.0
2)
2.0
1.0
1 .0
C
1)
2.0
1.0
2.0
2)
1.0
2.0
2.0
D
1)
1 .0
2.0
2.0
2)
2.0
4.0
2.0
Means
1.38 mm
1.75 mm
1.50 mm
Standard
Deviation
0.52
1 .04
0.53

71
Table 4
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Interdental
Thickness Discrimination
Conditio n
Stimul us
Pai rs
Normal
Anes thetized
Anesthetized and Pressure
10 mm -
11 mm
62.5%
57%
50%
1 0 mm -
1 2 mm
100
87.5
100
1 0 mm -
1 3 mm
100
87.5
100
1 0 mm -
14 mm
100
100
100

72
mi di ine. (Table 5: X = 1.69 mm and X = 1.62 mm, respectively)
Subjects, as a group, found it easier to discriminate between
positions to the left of midline under the pressure condition
(X = 1.25 mm).
The mean percent of correct subject responses per
stimulus pairs for jaw positions to the left of midline are
presented in Table 6. These data illustrate that subject
performance reached 100% for the normal and anesthesia con¬
ditions when the difference between the pair of positions
reached 2.5 mm. Only 2.0 mm difference was necessary for
100% performance under the pressure condition. Moreover, the
group means presented in Table 5 and the mean percent of cor¬
rect subject responses presented in Table 6 fo.r discrimina¬
tion of jaw positions to the left of midline suggest that
anesthesia had no effect on the subject's discriminative
abilities while pressure to the TMJ, contralateral to the
anesthesia, enhanced performance somewhat. It should be
noted that pressure was always applied to left TMJ capsule,
or, for this task, to the side of jaw movement.
Subject performance scores, group means, and S.D.'s
are presented in Table 7 for the task of discrimination be¬
tween pairs of lateral jaw positions to the right of midline.
The group means presented in Table 7 suggest that this group
of subjects performed most accurately under the normal
condition (X = 1.12 mm) and performed least accurately under
the pressure condition (X = 2.06 mm). The group mean for the
anesthesia condition (X = 1.45 mm) fell between the two other

73
Table 5
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination for the Left
Condition
Subject
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
3.0 mm
1 .0 mm
1 .0 mm
2)
2.0
1 .5
1 .5
B
1)
LO
o
1.0
0.5
2)
1.5
1.0
ro
o
C
1)
1.0
1 .5
0.5
2)
1.0
1 .0
0.5
D
1)
2.0
2.5
1.5
2)
2.5
3.5
2.5
Means
1.69 mm
1.62 mm
1.25 mm
Standard
Deviation
0.84
0.92
0.76

74
Tab!e 6
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Jaw Position Discrimination to the Left
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm -
0.5
mm
37.5%
87.5%
37.5%
0
mm -
1.0
mm
50
62.5
75
0
mm -
1.5
mm
50
75
75
0
mm -
2.0
mm
75
100
87.5
0
mm -
2.5
mm
87.5
87.5
100
0
mm -
3.0
mm
100
100
100
0
mm -
3.5
mm
100
100
100
0
mm -
4.0
mm
100
100
100
0
mm -
4.5
mm
100
100
100
0
mm -
5.0
mm
100
100
100

75
Table 7
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Lateral Jaw
Position Discrimination to the Right
Condition
Sub j ect
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
1 ,
. 5 mm
2.
. 5 mm
2.
. 5 mm
2)
1 .
.0
1 .
.0
1 .
.0
B
1)
2.
.0
1 .
,0
2.
.0
2)
1 .
.0
1 .
.5
2.
.0
C
1)
1 .
.0
0.
,5
1 .
.0
2)
0.
. 5
0.
.5
0.
.5
D
1)
0.
.5
1 .
,5
4.
.5
2)
1 ,
.5
3.
.0
3.
.0
Means
1.12 mm
1.45 mm
2.06 mm
Standard
Deviation
0.52
0.23
0.74

76
Table 8
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination of
Lateral Mandibular Position Discrimination to
the Right
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm
-
0.5
mm
37.5%
25%
25%
0
mm
-
1 .0
mm
75
50
50
0
mm
-
1.5
mm
87.5
87.5
50
0
mm
-
2.0
mm
100
87.5
75
0
mm
-
2.5
mm
100
87.5
75
0
mm
-
3.0
mm
100
100
87.5
0
mm
-
3.5
mm
100
100
100
0
mm
-
4.0
mm
100
100
87.5
0
mm
-
4.5
mm
100
100
100
0
mm
5.0
mm
100
100
100

77
condition means.
Table 8 presents the mean percent of correct subject
responses per stimulus pair for the task of lateral jaw posi¬
tion discrimination to the right of midline. These data
demonstrate also that subjects' ability to perceive differ¬
ences in positions to the right of midline was hampered by
the application of pressure to the left TMJ capsule.
Anterior-pos terior jaw position discrimination
Table 9 presents the individual and group performance
scores for anterior-posterior jaw position discrimination.
The group means illustrate that the subjects'; performance
was equal for the anesthesia and the pressure conditions.
Table 10 presents the mean percent of correct subject re¬
sponses per stimulus pair for this task. Subjects per¬
formed less accurately in discrimination between pairs of
anterior-posterior jaw positions under the normal control
condition than under the experimental conditions. 100%
performance was attained when the difference between pairs
was 1.0 mm for the anesthesia and the pressure conditions.
For the normal condition, 100% performance was not reached
until the difference between pairs of jaw positions was
2.5 mm.
Discrimination of interdental weights
Individual and group performance scores for the task
of interdental weight discrimination can be found in Table
11. The anesthesia condition had little effect on subjects'

78
Table 9
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Anterior-Posterior
Jaw Position Discrimination
Condi tion
Subject
Trial
Normal
Anesthetized
Anesthetized and Pressure
A
1)
1 .5 mm
0.5 mm
0.5 mm
2)
2.5
0.5
0.5
B
1)
0.5
0.5
0.5
2)
0.5
0.5
1.0
C
1)
0.5
0.5
0.5
2)
0.5
1 .0
1 .0
D
1)
0.5
1 .0
1 .0
2)
2.0
LO
o
0.5
Means
1.06 mm
0.62 mm
0.68 mm
Standard
Deviation
0.82
0.94
0.23

79
Table 10
Mean Percent of Correct Subject Responses per
Stimulus Pair on a Measure of Discrimination
of Anterior-Posterior Jaw Positions
Condition
Stimulus Pairs Normal Anesthetized Anesthetized and Pressure
0
mm -
• 0.
.5
mm
87.
.5%
75%
75%
0
mm -
• 1.
.0
mm
100
100
100
0
mm -
• 1.
.5
mm
75
100
100
0
mm -
â–  2,
.0
mm
87.
,5
100
100
0
mm -
â–  2,
.5
mm
100
100
100
0
mm -
â–  3,
.0
mm
100
100
100

80
Table 11
Individual Performance Scores and Group Means,
Ranges, and S.D.'s for a Task of Interdental
Weight Discrimination
Condition
Subject
Trial
Normal
Anes thetized
Anesthetized and Pressure
A
1)
5.0 gms
14.0 gms
5.0 gms
2)
6.0
6.0
5.0
B
1)
13.0
4.0
11.0
2)
11.0
4.0
12.0
C
1)
7.0
5.0
2.0
2)
8.0
6.0
6.0
D
1)
4.0
6.0
12.0
2)
7.0
12.0
16.0
Means
7.62 gms
7.12 gms
8.62 gms
Standard
Deviation
3.01
3.75
4.47

81
ability to discriminate between paired weights. Group means
are 7.62 gms for the normal condition and 7.12 gins for the
anesthesia condition. Pressure appeared to make discrimina¬
tion between interdental weights more difficult. The mean
difference required was 8.62 gms for this condition.
Summary: perceptual measures
Anesthesia to the right auriculotemporal nerve appeared
to have a mild disruptive influence on this group of subjects'
abilities to discriminate between the thickness of pairs of
blocks placed interdentally. Pressure to the contralateral
(left) TMJ capsule restored discriminative ability somewhat
(Tables 3 and 4) .
Pressure to the left TMJ appeared to enhance subject
performance of tasks where anesthesia had no disruptive
effects. These tasks include Thilander's task of replicating
a standard interdental space ten times (Table 1), discrimi¬
nation between pairs of lateral jaw positions to the left of
midline (Table 5), and discrimination between pairs of
anterior-posterior jaw positions (Table 9). On the other
hand, pressure to the left TMJ capsule appeared to be dis¬
ruptive of subjects' ability to discriminate between pairs
of lateral jaw positions to the right of midline (Tables 7
and 8). Pressure appeared to have a disruptive effect on
subjects' ability to discriminate between the weights of
capsule pairs placed between the incisors (Table 11). Neither
of the experimental conditions appeared to influence the
subjects' performance on Thilander's task of duplicating a
standard jaw position when that task ia analyzed by the mean

82
difference of jaw positions from the standard postion.
Sentence
Figure 13 combines a tabular and graphic representation
of the vertical jaw displacement (N = 4) for the seventeen
phonemes under each of the three conditions. The mean, range,
and standard deviation are entered below each phoneme. Figure
14 presents the complimentary data for horizontal mandibular
displacement. Since measures from the film were made at one
and one-half life size (Chapter Two), all measurement values
were reduced by one-third to achieve absolute values. Statis¬
tical significance could not be assessed due to the small
number of observations.
Figure 13 demonstrates that similar vertical patterns of
jaw movement are maintained under each of the test conditions.
The most closed jaw postures are observed for the /tj / in
"watches" and the /t/ in "XV." The greatest amount of mandi¬
bular displacement is observed for the /a/ in "Cojnnie" and the
/a,/ in "watches." These observations are compatible with
previous research findings (Kent and Moll, 1972 and Owens,
1 973).
In general, vertical jaw displacement was greatest for
the anesthesia condition and least for the pressure condition.
Under anesthesia, jaw displacement was equal to normal for the
initial speech sounds in the sentence. As the amount of re¬
quired displacement increased for the open sounds in "Connie"
and "watches," the jaw opened more for the anesthesia condi¬
tion than for the normal condition. As the

8
Phoneme
i
1
V
n
NJ I
k
cu
n
w
cu
tf
t
1
V
1
e
m
Normal —
1 N 1
JH E
£ I
N G
£ £
M I
E W
A T
H e
S T
E E
v L_
: w
T H
M £
Mean
3.35
5.19
3.35
3.52
3.52
7.37
5.53
5.70
7.70
0.84
-.34
2.18
1.67
3.02
3.52
3.35
Range
4.69
5.36
5.36
6.03
5.36
9.38
8.04
8.71
8.04
2.68
3.35
4.02
3.35
4.69
5.36
4.69
Std.Dev. 2.12
Anesthetized •—
2.34
2.44
2.75
2.58
4.17
3.92
4.11
3.52
1.38
1 .39
1 .84
1.59
1.93
2.64
2.12
Mean
3.52
5.02
3.52
4.52
4.36
8.21
6.70
5.19
6.36
0.34
-.34
3.68
2.85
3.68
4.52
4.19
Range
6.03
4.69
3.35
6.70
5.36
8.04
4.02
7.37
8.71
3.35
4.02
3.35
3.35
4.69
4.02
3.35
Std.Dev. 2.59
Anesthetized an
2.08
Pre
1 .76
ss ure
2.81
2.28
3.64
2.12
3.34
3.89
1.59
1.77
1.59
1.58
1.93
2.14
1 .76
Mean
2.85
4.36
2.85
2.85
3.68
6.03
4.52
3.68
4.69
-.84
-1 .00
1 .68
1.34
1 .84
2.85
2.34
Range
5.36
5.36
4.69
4.02
4.69
4.02
2.60
4.02
5.36
3.35
4.69
4.02
2.68
4.69
3.35
4.02
Std.Dev
2.34
2.47
2.28
1 .84
1.93
1.97
1 .38
1.77
2.25
1 .58
2.08
2.01
1.54
2.27
1.70
2.01
1
3.52
6.70
2.90
3.18
2.68
1.41
3.18
4.69
2.21
Figure 13
Means, Ranges and S.O.'s of Vertical Jaw Positions Under Three
Conditions for 17 Sounds Selected From a Connected Apeech Sample (N”4)

84
amount of required jaw displacement decreased for the conso¬
nants at the end of "watches" and in "Tee Vee", the jaw began
to close sooner for anesthesia. Jaw displacement for the
/ tf / in "watches" and /1/ in "Tee Vee" appeared equivalent
for the two conditions. As the amount of required jaw dis¬
placement increased for the open sounds at the end of the
passage, the jaw opened more for the normal condition. This
is interpreted as over-shooting of the target position for
the production of open speech sounds.
On the other hand, pressure appeared to reduce vertical
displacement. It appeared to do so consistently over all the
speech elements in the speech sample, both open and closed.
The pattern of jaw posturing in the horizontal dimen¬
sion is similar also for the three conditions, Figure 14.
The most anterior jaw postures are observed for the /tj/ in
"watches" and the /t/ in "Tee Vee". The most retruded pos¬
tures are observed for the /a/ and /n/ in "Connie" and the
/«/ in "watches". These observations, again, are compatible
with previous research findings (Kent and Moll, 1972 and
Owens, 1973). The findings also support observations of the
hinge action of the mandible. That is, the greater the
vertical displacement of the mandible, the more retruded the
structure will be.
The effects of anesthesia and pressure observed in the
vertical dimensions are not readily apparent in the horizontal
plane. The path of jaw movement for any one condition inter¬
sects the others.

6
Phoneme
Normal •—
1
a
I N T_
1
1
_H E
V
E V
1
9
N 1
k
N G
1
Oy
CON
n
N I
1
w
E W
1
CLy
A T
$
H E
1
t
S I
In
|m
1
V
V E
i
: Ü
1
e
T H
1
m
M E
<
Mean
4.52
4.52
3.35
4.36
4.02
4.02
4.02
4.19
4.36
3.02
1 .84
2.68
3.02
3.35
3.86
3.68
4.36
Range
3.35
3.35
3.35
2.68
2.68
4.69
4.02
2.01
4.02
4.69
2.01
2.68
2.68
2.68
2.68
2.68
2.01
Std.Dev. 1.76
Anesthetized o-
1.76
1 .64
1 .28
1.22
1 .97
1.81
0.84
1.73
2.08
1 .00
1 .22
1 .59
1 .22
1.14
1 .28
1.16
Mean
4.19
3.68
3.18
4.19
4.36
5.19
5.02
4.19
4.69
3.02
2.34
2.84
3.02
3.35
4.36
4.36
4.86
Range
3.35
2.68
2.68
2.01
2.01
3.35
3.35
2.68
3.35
4.02
2.68
3.35
4.02
3.35
2.01
2.68
2.35
Std.Dev. 1.48
Anesthetized anc
1.16
Pres
1 .38
sure
0.84
A -*
0.86
1.38
1 .39
1.14
1 .64
1 .59
1.16
1.48
1.77
1 .44
1.16
1 .28
1 .48
Mean
4786
4.69
T7oI
4.19
4.36
5.02
4.69
3.52
4.19
2.18
2.01
3.52
3.02
4.02
4.02
3.86
4.86
Range
3.35
3.35
2.68
4.69
4.02
3.35
4.02
4.02
4.02
4.02
4.02
3.35
3.68
4.02
2.68
3.35
2.68
Std.Dev
1.48
1.85
1 .22
2.21
2.08
1.59
1.81
1 .76
1.76
1.77
1.73
1 .38
1 .28
1 .73
1.09
1.38
1.14
CD
CJ1
Figure 14
Means, Ranges and S.D.'s of Horizontal Jaw Positions Under Three
Conditions for 17 Sounds Selected From a Connected Speech Sample (N»4)

86
Analysis of Speech Tasks and Monspeech Oral Movements
The measurements of jaw position obtained from the pro¬
jected cinef1uorographic frames (as outlined in Chapter Two)
have been summarized relative to five parameters of mandibu¬
lar activity for the ten tasks. These parameters are: verti¬
cal jaw displacement, horizontal jaw displacement, range of
vertical jaw movement, range of horizontal jaw movement, and
duration or length of production. For each of these five
parameters, measurements were recorded to represent mandibu¬
lar activity throughout each task. These data were then sub¬
jected to descriptive analysis, that is, mean and standard
deviation and to a test of statistical significance based
upon the analysis of a repeated measures design. The results
of the descriptive analysis and a summary of the analysis of
repeated measures with the mean square, sum of squares, de¬
grees of freedom, and F statistic are presented in the ap¬
pendix. An F value was considered significant when p<.05.
In the repeated measures design, each subject is ob¬
served under each of the test conditions. This study repre¬
sents a single factor repeated measures design where there
are three levels to the factor. Those levels are three test
conditions, that is, control, anesthesia, and anesthesia-
pressure.
The analysis of repeated measures provides an analysis
of variance in that the mean score for each condition is
compared with every other mean score. The analysis provides

87
a test of the statistical hypothesis (null hyphthesis),
Ho: all test condition means are equal. The alternate
hypothesis, Hj , states that at least one pair of condi¬
tion means differ significantly.
In order to determine between which pair of means
statistical significance exists, the Newman-Keuls Procedure
(Keppel, 1973) was utilized as a second step in the statis¬
tical analysis. This procedure allows for multiple com¬
parisons of the test condition means and indicates between
which pairs a statistical significance exists. A summary
of the Newman Keuls analysis, that is, the paired condi¬
tion values, are presented for each of the ten tasks ana¬
lyzed statistically, Tables 12 through 21.
The values for vertical and horizontal displacement
and the values for the range of motion are presented in
millimeters. The values for duration of production are
presented in number of frames. At a filming rate of 24
frames per second, the time between each frame is 40 milli¬
seconds .
Nonspeech Oral Movements
Elevation of tongue tip
The amount of vertical mandibular displacement was
measured at three points during the movement, requiring
each subject to elevate his tongue tip. As listed in
Table 12, these measurements of vertical jaw displacement
were taken when the tongue contacted the alveolar ridge,

88
Table 12
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Tongue Tip Elevation
Measures Condition Pairs
Vertical Displacement
Tongue Contact
Tongue Release
Lowest Tongue
Normal/
Anesthes i a
10.45/10.72
10.92/10.38
12.80/13.00
Normal/
Anesthesia-
Pressure
10.45/7.97*
10.92/7.24*
12.80/9.31*
Anesthesia/
Anesthesia-
Pressure
10.72/7.97
10.38/7.24*
13.00/9.31*
Horizontal Displacement
Tongue Contact
Tongue Release
Lowest Tongue
6.28/6.62
6.36/6.36
6.77/6.97
6.28/6.12
6.36/5.86
6.77/6.28
6.62/6.12
6.36/5.86
6.97/6.28
Ranqe of Vertical
Movement
Tongue Contact
Tongue
Tongue Contact
Release
Tongue Release
Tongue
to Lowest
to Tongue
to Lowest
2.51/2.26
1.17/1.51
2.43/2.68
2.51/2.34
1.17/1.43
2.43/2.60
2.26/2.34
1.51/1.43
2.68/2.60
Ranqe of Horizontal Movement
Tongue Contact
Tongue
Tongue Contact
Release
Tongue Release
Tongue
to Lowest
to Tongue
to Lowest
0.34/0.67
0.59/0.76
0.67/1.09
0.34/0.84
0.59/0.84
0.67/0.92
0.67/0.84
0.76/0.84
1.09/0.92
Duration of Production
Tongue Contact to Lowest
Tongue 20.50/25.50 20.50/24.63 25.50/24.63
Tongue Contact to Tongue
Release 10.00/14.63*10.00/12.75 14.63/12.75
Tongue Release to Lowest
Tongue 10.50/10.88 10.50/11.88 10.88/11.88
p<. 05

89
when the tongue just released contact with the alveolar
ridge, and when the tongue was in its lowest posture prior
to elevation for the following trial. Analysis of these
three vertical measures revealed that no significant dif¬
ferences existed between the control and the anesthesia
condition, Table 12. However, further analysis revealed
that the vertical displacement of the jaw was reduced
significantly (p<.05) by the application of a light pres¬
sure. The amount of horizontal displacement, measured at
these same three points, was not significantly altered under
either of the experimental conditions.
The range of mandibular movement in the vertical and
horizontal planes was calculated between tongue contact with
the alveolar ridge and at the point when the tongue was in
its lowest posture, between the time the tongue contacted the
alveolar ridge and released contact, and between the time the
tongue released contact and assumed its lowest posture. Sta¬
tistical analysis of these data revealed no significant dif¬
ferences between any of the three pairs of conditions.
Therefore, the range of jaw movement was not altered by anes¬
thesia of the right auriculotemporal nerve, nor was the range
of movement altered by a subsequent application of pressure
to the left TMJ capsule.
The amount of time between these same three points was
calculated also. Although the duration of production appeared
increased by the experimental procedures, only the time re¬
quired to complete the move from tongue contact to tongue re¬
lease was significantly increased by the application of

90
anesthesia (p<.05).
Elevation of tongue dorsum
The measurements and calculations made for this task
requiring each subject to elevate the dorsum of the tongue
three times were similar to those for the preceding task of
tongue tip elevation, Table 13. No statistically significant
differences existed between conditions for the measures of
tongue dorsum elevation. However, there was a trend for the
length of production to increase with anesthesia and increase
even more with the application of pressure.
Summary: nonspeech oral movements
When comparing the two tasks of tongue elevation, it
was observed that the jaw was vertically displaced more for
tongue tip elevation than for tongue dorsum elevation. This
was unexpected since speech tasks involving similar speech
movements would result in less vertical displacement of the
mandible for 1ingual-alveolar sound production than for
production of 1 ingua1 -velar sounds.
More expected was the greater horizontal displacement
of the mandible for tongue dorsum elevation. The range of
horizontal movement was also greater for this task suggesting
that in order to achieve 1ingual-velar contact, the tongue
and jaw act in unison to retrude and elevate the tongue.
The time required to complete a trial appears to be equivalent
for both of the nonspeech tasks. In addition, 1ingual-alveo-
lar and 1ingual-velar contact appeared to be maintained
equally as long for each task.

91
Table 13
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Tongue Dorsum Elevation
Measures Condition Pairs
Vertical Displacement
Normal/
Anes thes i a
Normal/
Anesthesia-
Pressure
Anesthesia/
Anesthesia-
Pressure
Tongue Contact
7.91/6.28
7.91/7.37
6.28/7.37
Tongue Release
8.38/7.44
8.38/8.04
7.44/8.04
Lowest Tongue
10.25/8.78
10.25/8.58
8.78/8.58
Horizontal Displacement
Tongue Contact
8.38/7.24
8.38/7.44
7.24/7.44
Tongue Release
8.98/8.11
8.98/7.77
8.11/7.77
Lowest Tongue
7.44/7.04
7.44/6.62
7.04/6.62
Ranqe of Vertical Movement
Tongue Contact to Lowest
Tongue
2.34/2.68
2.34/1.51
2.68/1 .51
Tongue Contact to Tongue
Release
0.92/2.26
0.92/1.76
2.26/1.76
Tongue Release to Lowest
Tongue
2.60/2.85
2.60/2.77
2.85/2.77
Ranqe of Horizontal Movement
Tongue Contact to Lowest
Tongue
2.10/2.34
2.10/1.84
2.34/1.84
Tongue Contact to Tongue
Release
1.17/1.93
1.17/1.09
1 .93/1.09
Tongue Release to Lowest
Tongue
1.84/2.26
2.84/1.68
2.26/1.68
Duration of Production
Tongue Contact to Lowest
Tongue
20.75/22.75
20.75/25.25
22.75/25.25
Tongue Contact to Tongue
Release
9.63/11.98
9.63/13.13
11.98/13.13
Tongue Release to Lowest
Tongue 11.13/10.88 11.13/12.13 10.88/12.13
p¿.05

92
Diphthong Production
Diphthong: /a I/
The amount of vertical and horizontal displacement was
measured at the initiation and the completion of diphthong
production. Analysis of the two vertical measures revealed
that anesthesia did not alter the initial, starting position
of the jaw, Table 14. The starting position was reduced
significantly by the application of pressure (p .05). The
final, or ending, vertical position was not altered signifi¬
cantly by either of the experimental conditions. However,
the range of vertical movement from the starting to the ending
position was reduced significantly by the application of
pressure. The amount of time required to produce /a I/ was
reduced significantly by anesthesia. Neither the initial and
final horizontal displacement nor the range of horizontal
movement varied significantly under the experimental condi-
tions.
Diphthong: /el/
The paired values for the three conditions of /el/
production are presented in Table 15. Again, while anesthesia
did not alter the starting position of the jaw, the application
of a light pressure significantly reduced this position. The
range of vertical movement did not vary significantly between
any of the condition pairs. However, the range of horizontal
movement was reduced significantly by the application of
pressure when compared to the normal condition, but not when
compared to the anesthesia condition.

93
Table 14
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /a I /
Measures Condition Pa i rs
Normal/ Anesthesia/
Normal/ Anesthesia- Anesthesia-
Vertical Displacement Anesthesia Pressure Pressure
Initial
11.22/11.06
1 1 . 22/8.44*
1 1 .06/8.44*
Final
4.80/4.13
4.80/3.68
4.13/3.68
Horizontal Displacement
Initial
5.14/5.31
5.14/5.42
5.31/5.42
Final
4.64/4.41
4.64/4.42
4.41/4.42
Ranqe of Vertical Movement
6.36/6.98
6.36/4.75*
6.98/4.75*
Ranqe of Horizontal Movement
1.23/1.79
1.23/1.29
1.79/1.29
Duration of Production
7.83/6.42*
7.83/7.25
6.42/7.25
p¿. 05

94
Table 15
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /el/
Measures Condition Pairs
Vertical Displacement
Normal/
Anesthesia
Normal/
Anes thesia-
Pressure
Anesthesia/
Anesthesia-
P res s ure
Initial
10.72/10.61
10.72/8.82*
10.61/8.82*
Final
5.14/5.14
5.14/4.30
5.14/4.30
Horizontal Displacement
Initial
5.81/5.25
5.81/5.30
5.25/5.30
Final
3.74/3.74
3.74/3.85
3.74/3.85
Ranqe of Vertical Movement
5.70/5.53
5.70/5.58
5.53/5.58
Ranqe of Horizontal Movement
2.34/1.73
2.34/1.62*
1.73/1 .62
Duration of Production
8.42/6.83
8.42/7.50
6.83/7.50
p-c.05

95
The time required to produce /el/ was reduced significantly
by anesthesia.
Diphthong: /aTT/
Paired values for the measures of /all/ production are
presented in Table 16. The effects of the experimental pro¬
cedures are similar to those found on the preceding task of
/a I/ and /el/ production. Pressure had a statistically sig¬
nificant effect towards reducing vertical jaw displacement
for the starting position. The application of pressure also
reduced the vertical displacement for the ending mandibular
position. Horizontal displacement did not vary significantly
between any of the condition pairs.
The range of vertical excursion of the mandible also
was reduced significantly by the application of pressure.
However, the range of horizontal movement was not altered
significantly by either of the experimental conditions.
Neither was the amount of time required to produce the diph¬
thong altered by the experimental procedures.
Diphthong: /a I/
Condition pairs for the production of /a I/ are listed
in Table 17. No significant differences existed for any of
the paired values for the production of this diphthong.
However, a trend for pressure to reduce the vertical posture
of the mandible for the initial and final jaw positions was
apparent.

96
Table 16
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /all/
Measures Condition Pairs
Vertical Displacement
Norma 1/
Anes thesia
Norma 1/
Anesthesia-
Pressure
Anesthesia/
Anesthesia-
Pressure
Initial
12.84/12.34
12.84/9.33*
12.34/9.33*
Final
6.31/5.14
6.31/4.58*
5.14/4.58
Horizontal Displacement
Initial
6.14/5.86
6.14/5.81
5.86/5.81
Final
4.91/4.64
4.91/4.91
4.64/4.91
Ranqe of Vertical Movement
6.59/7.37
6.59/4.80*
7.37/4.80
Ranqe of Horizontal Movement
1.40/1.34
1.40/1.06
1 .34/1.06
Duration of Production
9.17/9.83
9.17/8.42
9.83/8.42
p<. 05

97
Table 17
Results of Newman Keuls Analysis:
Condition Pairs for Measures
of Diphthong Production: /ol/
Measures Condition Pairs
Vertical Displacement
Initial
Final
Norma 1/
Anesthesia
8.54/8.43
5.31/5.36
Normal/
Anesthesia-
Pressure
8.54/7.37
5.31/4.52
Anesthesia/
Anesthesia-
Pressure
8.43/7.37
5.36/4.52
Horizontal Displacement
Initial
Final
5.53/5.42
5.02/5.31
5.53/5.86
5.02/5.53
5.42/5.86
5.31/5.53
Ranqe of Vertical Movement
3.40/3.30
3.40/3.07
3.30/3.07
Ranqe of Horizontal Movement
1 .29/0.95
1 .29/1.06
0.95/1.06
Duration of Production
6.83/6.42
6.83/5.92
6.42/5.92
p<. 05

98
Summary of diphthong production
The application of a light pressure to the left TMJ
capsule had the effect of reducing the amount of vertical
jaw displacement. The reduction was statistically signifi¬
cant for those diphthongs requiring greater initial displace
ment: that is /al/, /el/, and / alf/. The range of vertical
movement from the initial to final position was also reduced
significantly by the application of pressure for the diph¬
thongs / a I / and /ali/. It should be noted that the produc¬
tion of these diphthongs requires greater initial jaw dis¬
placement than for the other diphthongs /el/ and loll.
The amount of horizontal displacement for the initial
and final positions of the mandible were not altered by the
experimental procedures. The range of horizontal movement
was altered significantly (reduced) by pressure only for the
production of /el/.
The length of time required to produce each diphthong
was not altered significantly by the application of pressure
The amount of time required to produce /a I/ and /el/ was
reduced significantly by anesthesia.
Vowel-Consonant-Vowel Production
/ i s i /
Anesthesia appeared to reduce the amount of vertical
and horizontal displacement for all sound elements of this
VCV. However, only the initial /i/ was reduced signifi¬
cantly, Table 18. The range of horizontal movement also

99
Table 18
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /isi/
Measures
Normal/ Anesthesia/
Verti cal Di s pi a cement
Normal
Anesthesia
Anesthesia-
Pres sure
Anesthesia-
Pressure
Initial Vowel /i/
Consonant /s/
Final Vowel /i/
2.30/2.01
-0.67/-1.04
1.34/1.11
2.30/1.71
-0.67/-0.52
1.34/1.27
2.01/1.71
-1.04/-0.52
1.11/1.27
Horizontal Displacement
Initial Vowel /i/
Consonant Is/
Final Vowel /i/
4.46/3.50*
2.23/2.01
3.71/3.35
4.46/3.79
2.23/2.30
3.71/3.71
3.50/3.79
2.01/2.30
3.35/3.71
Ranqe of Vertical Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
1.27/2.34
2.97/3.05
2.30/2.46
1.27/0.60
2.97/2.53
2.30/2.08
1 .34/0.60
3.05/2.53
2.46/2.08
Ranqe of Horizontal Movement
Inita1 Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
2.23/1.34
2.23/1.56
1.78/1.41
2.23/1.49
2.23/1.64
1.78/1.34
1.34/1 .49
1.56/1.64
1.41/1.34
Duration of Production
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
12.10/11.57
4.00/3.99
8.55/7.56
12.10/10.80*11.57/10.80
4.00/4.78 3.99/4.78
8.55/6.00 7.56/6.00
p .05

100
appeared reduced somewhat, although the amount was not
significant. The length of time required to produce /isi/
appeared not to be influenced by the anesthesia.
Pressure appeared to reduce further the amount of
vertical displacement for each of the sound elements, but
the reduction was not significant. The range of movement,
both in the vertical and horizontal dimension, were reduced
also under anesthesia, but again, the reduction from normal
did not reach significant levels. The duration of the pro¬
duction was significantly shorter under the pressure condi¬
tion.
/asa/
No significant effect was observed for comparisons of
the normal and anesthesia conditions for production of the
VCV /asa./, Table 19. The reduction of jaw displacement and
range of motion values observed for the production of /isi/
were notapparent for /asa/.
On the contrary, the application of a light pressure
significantly reduced the amount of vertical displacement
for the sound element /s/ and the range of vertical movement
from /s/ to the final la-1. In general, it was observed
throughout this sample of speech that pressure reduced the
amount of displacement and the range of movement when compared
to the values obtained under the normal condition. However,
only the two differences reported above were significant.
/ i k i /
The production of /iki/ was not influenced significantly

101
Table 19
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /usa./
Measures Condition Pairs
Normal/
Normal/
Anesthesia-
Anesthesia/
Anes thesia-
Vertical Displacement
Anesthesia
Pressure
Pressure
Initial Vowel /a/
6.48/6.55
6.48/6.63
6.55/6.63
Consonant /s/
-0.96/-0.96
-0.96/-0.52*
-0.96/-0.52
Final Vowel /a/
4.17/3.28
4.17/3.72
3.28/3.72
Horizon tal Displacement
Initial Vowel /a/
5.36/5.21
5.36/5.06
5.21/5.06
Consonant /s/
2.46/2.23
2.46/2.53
2.23/2.53
Final Vowel /a./
5.06/4.47
5.06/4.76
4.47/4.76
Ranqe of Vertical Movement
initial Vowel to Final
Vowel
2.61/3.57
2.61/2.90
3.57/2.90
Initial Vowel to Consonant
7.44/7.52
7.44/7.15
7.52/7.15
Consonant to Final Vowel
5.21/4.40
5.21/4.31*
4.40/4.31
Ranqe of Horizontal Movement
Ini ti a 1 Vowel to Final
Vowel
3.20/3.20
3.20/2.75
3.20/2.75
Initial Vowel to Consonant
3.13/3.06
3.13/2.68
3.06/2.68
Consonant to Final Vowel
2.75/2.53
2.75/2.46
2.53/2.46
Duration of Production
Initial Vowel to Final
Vowel
11.22/10.78
11.22/11.22
10.78/11.22
Initial Vowel to Consonant
4.55/4.44
4.55/5.00
4.44/5.00
Consonant to Final Vowel
6.67/6.33
6.67/6.22
6.33/6.22
p<. 05

102
by the experimental procedures utilized in this study,
Table 20. Some small reductions were observed for horizon¬
tal displacement of each sound element and in the length
of production, however, none of these values approached
significanee.
/a. kg/
The vertical displacement for the final /a-/ was sig¬
nificantly reduced under the anesthesia condition, Table 21.
The vertical displacement for the sound element /k/ was re¬
duced also, but not significantly. Vertical displacement for
the initial /a./ was greater under anesthesia. Again, the
difference was not significant. The range of vertical move¬
ment from the initial /a./ to the final /a-/ and from the ini¬
tial /a/ to the /k/ were significantly greater under anesthe¬
sia. This most likely reflects the reduction in the dis¬
placement for the /k/ and final /a./. Horizontal displace¬
ment and horizontal range of movement were reduced also by
anesthesia, but not significantly.
Vertical displacement for the final /a./ was signifi¬
cantly less under the pressure condition when compared to the
normal condition. The range of vertical movement from the
initial /cl/ to final /a./ and from the /k/ to final /a-/ was
reduced significantly under pressure. Further, pressure
significantly reduced the range of vertical movement from the
initial /a./ to the /k/ when compared to the anesthesia
condi ti on.

103
Table 20
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production: /iki/
Measures
Vertical Displacement
Initial Vowel /i/
Consonant /k/
Final Vowel /i/
Condition Pairs
Normal/ Anesthesia/
Normal/ Anesthesia- Anesthesia-
Anesthesia Pressure Pressure
3.50/3.64 3.50/3.42 3.64/3.42
2.68/3.06 2.68/2.61 3.06/2.61
2.83/3.20 2.83/2.90 3.20/2.90
Horizontal Displacement
Initial Vowel /i/
Consonant /k/
Final Vowel /i/
4.69/4.09
4.69/4.24
4.40/4.09
4.69/4.39
4.69/4.40
4.40/4.40
4.09/4.39
4.24/4.40
4.09/4.40
Range of Vertical Movement
Initial Vowel to Final
Vowel 0.82/0.89
Initial Vowel to Consonant 0.96/0.97
Consonant to Final Vowel 1.04/1.12
0.82/0.67
0.96/0.89
1.04/0.59
0.89/0.67
0.97/0.89
1.12/0.59
Range of Horizontal Movement
Initial Vowel to Final
Vowel 0.44/0.52 0.44/0.52
Initial Vowel to Consonant 0.37/0.45 0.37/0.45
Consonant to Final Vowel 0.45/0.52 0.45/0.52
0.52/0.52
0.45/0.45
0.52/0.52
Duration of Production
Initial Vowel to Final
Vowel 11.78/11.00 11.78/10.55 11.00/10.55
Initial Vowel to Consonant 3.78/2.89 3.78/3.55 2.89/3.55
Consonant to Final Vowel 8.00/8.11 8.00/7.00 8.11/7.00
p <. 05

104
Table 21
Results of Newman Keuls Analysis:
Condition Pairs for Vowel-Consonant-Vowel
Production:
: /aka/
Measures
Condition Pairs
Vertical Displacement
Initial Vowel /a./
Consonant /k/
Final Vowel /a-/
Normal/
Anesthesia
7.67/8.41
4.40/3.05
6.85/3.80*
Normal /
Anesthesia-
Pressure
7.67/7.59
4.40/4.39
6.85/4.32*
Anesthesia/
Anesthesia-
Pressure
8.41/7.59
3.05/4.39
3.80/4.32
Horizontal Displacement
Initial Vowel /«-/
Consonant /k/
Final Vowel /a-/
5.58/5.21
5.43/4.68
5.34/4.98
5.58/5.51
5.43/5.51
5.34/5.51
5.21/5.51
4.68/5.51
4.98/5.51
Ranqe of Vertical Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
2.61/4.61*
3.50/5.51*
2.61/1.79
2.61/2.38*
3.50/3.20
2.61/0.82*
4.61/2.38
5.51/3.20*
1 .79/0.82
Ranqe of Horizontal Movement
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
1.27/1.19
0.82/0.96
0.96/0.89
1.27/0.74
0.82/0.67
0.96/0.52
1.19/0.74
0.96/0.67
0.89/0.52
Duration of Production
Initial Vowel to Final
Vowel
Initial Vowel to Consonant
Consonant to Final Vowel
9.89/10.22
3.67/4.33
6.22/5.89
9.89/9.89
3.67/3.67
6.22/6.22
10.22/9.89
4.33/3.67
5.89/6.22
p<. 05

105
Summary: vowel-consonant-vowel production
With only a few exception, both of the experimental
conditions tended to reduce the vertical and horizontal dis¬
placement of the jaw for VCV's studied. The range of verti¬
cal and horizontal movement was reduced usually by the exper¬
imental conditions. The exception was the production of
/akaV where anesthesia significantly increased the range of
vertical movement. This most likely reflects the severe
reduction in the displacement of the final /a-/ by anesthesia.
With the two exceptions, differences between the values
for the anesthesia and the pressure conditions were not signi¬
ficant. The exceptions were a significant reduction by
pressure of the vertical displacement for the /s/ in /a.saj,
Table 19, and a significant reduction by pressure of the
range of vertical movement from the initial /a./ to the /k/
i n ¡aJf.a./ , Table 21 .

CHAPTER FIVE
DISCUSSION
The sensory receptors and the role they play in
monitoring and regulating intelligible speech is not yet
clearly understood. There have been a number of studies
whose purpose it was to study mandibular motion during
speech function, to define parameters of mandibular kines¬
thesia, and to determine what structures are responsible
for perceiving and transmitting information of mandibular
kinesthesia or mandibular position sense. The work of
Thilander (1961) and her colleagues (Ransjo and Thilander,
1963 and Larsson and Thilander, 1964) implicated the
sensory receptors in the TMJ and it's ligament as, at least,
having partial responsibility for monitoring perception of
mandibular position. The present study was designed to
investigate the role of the sensory mechanism of the TMJ for
monitoring the movement and posturing of the mandible during
selected speech and nonspeech tasks. Specifically, the
purpose was first to assess the effect of a unilateral
anesthetization of the auriculotemporal nerve on jaw function
and secondly to assess subsequently the effects of a light
pressure to the contralateral TMJ capsule.
106

107
Anesthetization of the Auriculotemporal Nerve
Perceptual Measures
The anesthetization procedure utilized in this study
appeared to have little disruptive influence on subjects'
abilities to discriminate differences in pairs of jaw positions
or to discriminate between the weights of capsule pairs placed
between the teeth. The only observable alteration was a
slight disruption in the ability to discriminate differences
in interdental thicknesses (Table 3) and lateral jaw positions
to the right of midline (Table 7). The mean difference
necessary to discriminate the difference in the thickness of
block pairs was 1.38 mm under the control condition and in¬
creased to 1.75 mm for anesthesia. A difference limen of
1.12 mm was obtained for discriminating between pairs of jaw
positions fo the right of midline. The difference limen
increased to 1.45 mm under the anesthesia condition.
The results of the task which required subjects to
duplicate an interdental space were not supportive of pre¬
vious research findings (Thilander, 1961; Ransjo and Thilander,
1963; and Larsson and Thilander, 1964). The subjects in the
present experiment performed similarly under the normal and
anesthesia conditions. That is, the mean range of jaw posi¬
tions over ten trials attempting to duplicate a standard was
6.00 mm for the normal condition, Table 1. Additionally, the
mean jaw position (for ten trials) from the standard did
not differ noticable between

108
the normal and anesthesia conditions. The mean difference
from the standard was 3.60 mm for the normal and 3.42 for the
anesthesia, Table 2.
The effect of anesthesia on subjects' ability to dis¬
criminate between pairs of jaw postures to the left of midline
did not differ noticably as a result of anesthesia. The mean
distance required was 1.69 mm for the normal condition and
1.62 mm for the anesthesia condition.
Anesthesia appeared to have somewhat of an enhancing
effect on subjects' ability to differentiate between pairs of
jaw positions in the anterior-posterior dimension. The mean
difference required was 1.06 mm for the control condition and
was reduced to 0.62 mm under anesthesia.
It might be suspected that the apparent enhancing effect
of anesthesia was actually the result of subjects' famili¬
arity with the tasks. In order to facilitate data collec¬
tion, that is, avoid losing subjects to follow-up testing,
the testing of each subject was completed in one session.
Therefore, all subjects were tested under the control condi¬
tion first and were retested subsequently under the experi¬
mental procedures. In order to balance presentation of ex¬
perimental tasks, two subjects performed the tasks under
anesthesia first and two subjects performed under anesthesia-
pressure first. Therefore, we might speculate that any im¬
proved performance under the experimental conditions was the
result of learning, while reduced performance would reflect
disruption of sensory ability.

109
Finally, a task of interdental weight discrimination
was included in the test battery in order to determine the
role of the sensory mechanism of the TMJ in weight discrim¬
ination. The mean difference required in two weights before
subjects could detect a difference was 7.75 gms for the nor¬
mal condition and 7.12 gms for the anesthesia condition.
These data suggest that the sensory mechanism of the TMJ
does not have a role in monitoring load on the mandible,
at least in the weight range studied, that is 5 - 25 gms.
Sentence
For this sample of connected speech, anesthesia ap¬
peared to increase vertical jaw displacement rather consist¬
ently for open sound elements, Figure 13. Vertical dis¬
placement was greater for the anesthesia condition than
for normal or pressure conditions throughout the production
of the open sounds in the first half of the speech sample.
There appeared to be no influence of anesthesia on the
posturing of the mandible in the horizontal dimension for this
connected speech sample. Figure 14 illustrates that the
pattern of jaw movement for each of the three conditions
overlaps each of the other conditions. Moreover, a distinct
pattern is not discernable for any specific condition.
It appears that the anesthesia altered vertical pos¬
turing of the jaw differentially. During the production of
open sounds, anesthesia caused the jaw to maintain a greater
amount of displacement. However, for the closed sounds,
subjects' jaw posturing for the anesthesia condition approx¬
imated the posture observed for the normal condition. This

no
suggests that jaw positioning makes use of the tactile
feedback provided by the lingual-alveolar and lingual-palatal
contact provided in the production of the sound elements /tj/
and /t/. This is interesting since the anterior portion of
the tongue, used in the production of these two sounds, is
more richly innervated with sensory endings than the pos¬
terior. It further suggests that more than one sensory
system may provide information of jaw posturing.
Nonspeech Tasks
Anesthesia appeared not to influence any of the mea¬
sures of displacement or range of motion for the two tasks of
nonspeech oral movement. However, anesthesia did appear to
increase the length of time required to complete these tasks.
The increase was significant for tongue tip elevation from
the point when the tongue contacted the alveolar ridge to
the time when the tongue released that contact. Since this
is a period of limited jaw movement, as evidenced by the
limited range of movement during that time, it might be sus¬
pected that the sensory receptors of the TMJ process in¬
formation in the temporal domain. It may be proposed also
that the processing of this information is disrupted by
unilateral anesthetization of the auriculotemporal nerve.
Diphthong Production
The anesthetization procedure utilized in this study
appeared to have no influence on the displacement or the
range of motion of the mandible for the four diphthongs

Ill
studied. However, for the diphthongs /a I/ and /el/, anes¬
thesia significantly reduced the length of time used to pro¬
duce these sounds. This is interesting since anesthesia
appeared to increase the duration of the nonspeech oral
movements.
Vowel-Consonant-Vowel Production
Although significant differences resulted between values
for the normal and anesthesia conditions, ther did not appear
to be any consistent trend. There were no significant dif¬
ferences between the two conditions for the production of
/as cl/ or / i k i / . The significant reduction of horizontal
displacement for the initial /i/ in /isi/ , Table 18, and sig¬
nificant reduction in the vertical displacement of the final
/a/ in /a.ka/, Table 21, are difficult to explain except by
testing artifact. The significant increase in the measures
of the range of vertical movement for /o-ka/ most likely are
reflecting the affect of the significant reduction in vert¬
ical displacement for the final /a./.
Effect of Anesthesia: Summary
The data generated from this study suggests that there
appear to be some small disruptions in perception of jaw posi¬
tion, length of production, positioning of the mandible for
speech, and the range of motion throughout a speech task.
However, these data are not sufficient enough to support the
research findings of Thilander and her colleagues that sug¬
gested that the TMJ is active in the perception of jaw

112
posture. The findings of the present study are in agreement
with Siirila and Laine (1972) who found no disruption in sub¬
ject abilities on a test of interdental thickness discrimina¬
tion under bilateral anesthetization of the TMJ's,
The consistent disruption of abilities reported by
Thilander and her colleagues have not been replicated in two
seperate studies . Several explanations may account for the
differences in the results of these studies. Thilander util¬
ized an intracapsular injection procedure, whereas, the auri¬
culotemporal nerve was anesthetized in the present study. It
might be suspected that intracapsular injection results in
a more complete anesthetization of the TMJ sensory endings.
Thilander (1961) demonstrated that the TMJ capsule was
innervated by a major branch of the auriculotemporal nerve
and small slips from the masseteric and the deep temporal
nerves. It is the posterior and lateral aspects of the cap¬
sule that are the most richly innervated; these by the auri¬
culotemporal nerve. The anterior aspect of the capsule is
sparsely innervated by small twigs from the auriculotemporal,
posterior deep temporal, and masseteric nerves. The medial
aspect is served also by twigs from the auriculotemporal and
masseteric.
It may be hypothesized that feedback provided by the
masseteric and deep temporal nerves supply sufficient infor¬
mation to retain joint position sense even following the
blocking of the auriculotemporal nerve. Although, less fre¬
quently represented, the masseteric has a greater percentage

113
of large diameter (greater than 4/<() fibers (Thilander,
1961). These larger diameter fibers are more prone to carry
proprioceptive information. It might also be suspected that
bilateral blocking of the auriculotemporal nerve would pro¬
duce more serious disruptions of mandibular position sense.
However, further study is needed.
Further, the initial onset of jaw movement has been
attributed to rapidly adapting Type II mechanoreceptors,
which are quite numerous in the TMJ capsule. Type II
mechanoreceptors discharge briefly at the onset of joint
movement (Greenfield and Wyke, 1966). If this were true,
we would have expected much more variation between conditions
for the tasks such as a duplication of an interdental space
and in the initial jaw position for speech tasks. However,
only the results of vertical positioning for the production
of connected speech support this, Figure 13. For that task,
the mandible was displaced more for the starting position
under TMJ anesthetization than for the normal condition.
Jaw position was stabilized then by the slowly adapting motor
unit discharge of the Type I receptors responding to the
stretch of the muscle spindles in the mandibular elevators,
(Moyers, 1973).
We cannot rule out the possibility that the muscle
spindles provide sensory feedback important for jaw posi-
ioning. Thilander (1961) suggested that a more complete
disruption of the subjects' jaw position sense did not occur
because of proprioceptive feedback from the muscles of

114
mastication. Ricketts [1964) pointed out that the muscles
that control the action of the TMJ have a high innervation
ratio, with a high degree of sensitivity. Further, Kawamura
(1961) suggested that the temporal muscle may be the most
important muscle in regulating the position of the mandible.
Effect of Pressure
Since there was little disruption of mandibular
posturing caused by the anesthetization procedure in this
study, the restorative powers of pressure to the contralateral
joint (Larsson and Thilander, 1964) could not be adequately
assessed. However, pressure had its own observed effects.
Perceptual Measures
Pressure to the left TMJ capsule, subsequent to anes¬
thetization of the right auriculotemporal nerve was observed
to reduce the mean range of jaw position for the task of
duplicating an interdental space, Table 1. This might be
interpreted as enhancing the subjects' performance on this
task. Subjects also required less difference in block
thickness to judge differences, Table 3. Since it was ob¬
served that anesthesia appeared to impair subjects' ability,
the effect of pressure might be interpreted as restorative.
Subjects also found it easier to discriminate between jaw
positions to the left of midi i ri e when pressure was applied,
Table 5.
The most interesting effect of pressure on subject
performance for the perceptual measures was the impairment

115
of subjects' ability to discriminate lateral positions to the
right of midline, Table 7, This might have been expected
since jaw movement to the right requires lateral condylar mo¬
tion on the left side. These data suggest that pressure in¬
terfered with subjects' discriminative abilities either me¬
chanically or by reduction of sensory feedback.
Sentence
The effect of pressure on vertical and horizontal jaw
positioning for a connected speech passage are presented in
Figures 13 andl4 respectively. Although pressure had no
discernable effect of the horizontal positioning of the jaw,
this experimental procedure consistently reduced the amount
of vertical displacement throughout the speech sample. This
consistency suggests that pressure mechanically restricted
or reduced jaw movement during connected speech.
Nonspeech Tasks
The data for these tasks were presented in Tables 12
and 13. Table 12 illustrates that pressure significantly
reduced the amount of vertical displacement throughout the
task of tongue tip elevation. Again, the reduction in dis¬
placement is believed to be the result of a restriction of
the translational movement of the condyle. It is interesting
to note that pressure did not have the same reducing affect
for tongue dorsum elevation. It appears that pressure re¬
stricts movement past a certain vertical opening and that
opening was not reached for dorsum elevation.

116
Diphthong Production
Vertical jaw displacement was also significantly
reduced for the initial position for / a I /, /el/, and /al)/
(Tables 14, 15, and 16). Additionally, the range of verti¬
cal movement was significantly reduced for /a I/ and /aU/.
Again, these data suggest that pressure to the TMJ re¬
stricts jaw displacement and presents evidence that pres¬
sure also reduces the range of vertical movement.
Vowel-Consonant-Vowel Production
The data generated for the measures of mandibular
positioning, range of motion, and length of production for
the vowel-consonant-vowels suggest that the application of
pressure did not restrict jaw opening as severely as was
observed for the diphthong tasks. These data agree with
those obtained for diphthong production, in that maximum
jaw displacement for the low vowel /a./ did not exceed
8.5 mm. It was observed previously, for the diphthong
tasks, that jaw opening was not significantly reduced until
jaw displacement exceeded 10 mm.
It is interesting to note that pressure reduced the
time required to produce /isi/ (p<.05) and /iki, but not
/«-Sa./ and /aka/. This supports previous observations that
the TMJ offers some feedback in the temporal domain. It
suggests further that feedback is supplied differentially
between closed movements, such as for /isi and /iki/ and
for open jaw positions, such as for /asa/ and /aka/.
Also observed for the production of these sound

117
sequences was a reduction in the range of vertical movement.
Although it was significant only for the production of ¡a- IW,
it supports previous observations that pressure restricts
jaw movement. Notice also that /a.ka/ required the greatest
amount of jaw opening.
Effect of Pressure: Summary
These data have been interpreted to suggest that a
light pressure (1-2 pounds per square inch) applied to one
TMJ capsule reduces the amount of jaw opening and the range
of jaw movement throughout the production of a sequence of
sounds. Several explanations of this phenomena may be
forwarded. The findings of Thilander and her colleagues,
as to the restorative powers of pressure, might be reinter¬
preted. Larsson and Thilander (1964) and Ransjo and Thilan¬
der (1963) reported a reduction in the range of jaw opening
values when pressure was applied to a TMJ capsule contra¬
lateral to an anesthetized one. The previous researchers
may have observed a restriction in the opening movement of
the mandible. Since it was observed that pressure reduced
opening significantly when the jaw displacement required
exceeded 10.00 mm, Table 22, it is suspected that pressure
mechanically restricted the translatory motion of the condyle.
A second explanation is that pressure, even a light
pressure, might have displaced the condyle medially. In
which case, pain might have been generated by traction on
the nerve endings in the richly innervated lateral parts of
the capsule (Storey, 1968). The reduction in the opening

118
Table 22
The Amount of Jaw Opening (in mm)
for the Initiation of Each of Ten Tasks
Under the Normal and the Pressure Conditions
Task
Condition
Nonspeech
Tongue Tip Elevation
Tongue Dorsum Elevation
Normal/Pressure
10.45/7.97*
7.91/7.37
Diphthong Production
/ a 1/
/el/
/aU /
loll
11 .22/8.44*
10.72/8.82*
12.84/9.33*
8.54/7.37
Vowel - Consonant-Vowel Production
/ i s i /
/a-sa-/
/ i k i /
/ aka./
2.30/1.71
6.48/6.83
3.50/3.42
7.67/7.59
p<..05

119
of the mandible and the reduced range of mandibular motion
might have been compensatory to the presence of TMJ pain.
The data would suggest that pain becomes more noticable with
increased mandibular displacement.
The lack of improvement reported by Larsson and Thilan-
der (1964) for bilateral anesthesia may reflect the fact that
pressure was applied to a successfully anesthetized joint.
Thus, the sensation of pressure or pain was not available
to restrict jaw movement.
The results reported by Ransjo and Thilander (1963)
might be interpreted similarly. In that study, subjects with
unilateral joint dysfunction, due to malocclusion, found it
difficult to replicate an arbitrary jaw position. This abi¬
lity was not normalized when a light pressure was applied to
the side of dysfunction. However, when pressure was applied
to the normal side, the range of jaw positions for the ten
trials was significantly reduced. Again, these findings can
be interpreted as indicating a reduced sensation of the pres¬
sure of the effected side. Whereas, the sensation of pressure,
or pain, available to the normal side, restricted movement of
the condyle.
The fact cannot be overlooked that reduced jaw dis¬
placement may be the result of the cumulative effects of anes¬
thesia and pressure. Other researchers (McCroskey, 1958 and
Ringel and Steer, 1963) have reported that sensory disturb¬
ances of the oral structures are cumulative in their effect
on speech output. Since so few significant

120
differences between the normal and anesthesia conditions
were found in this study, it is suspected that reduced jaw
displacement is the result of pressure alone. However,
further study of speech production under a condition of
pressure alone is necessary. Such an investigation might
also include jaw displacement and movement under conditions
of varying amounts of pressure to ascertain if further
reduction results from further increases in pressure.
Conclusions
This study was designed to evaluate the effects of
anesthesia to the right auriculotemporal nerve and a subse¬
quent application of a light pressure to the left TMJ
capsule. The affects were assessed on a series of tasks
designed to measure subjects' abilities to discriminate
between jaw positions and weights of capsules held between
the central incisors. The affects of the experimental
procedures were assessed also on subjects' production of
speech elements including diphthongs, vowel-consonant-
vowel sequences, and a sample of connected speech and two
tasks of nonspeech oral movement. This study was undertaken
to define more clearly the role of the sensory mechanism of
the TMJ in monitoring the movement and positioning of the
mandible for these selected tasks.
The results of the present study suggest that uni¬
lateral anesthetization of the auriculotemporal nerve does
not consistently alter subjects' performance on the tasks

121
utilized in this study. It was suggested that the intra-
capsular injection procedure utilized by Thilander and her
colleagues resulted in a more complete blocking of the
sensory receptors or possibly that a bilateral block of
the auriculotemporal nerve might disrupt more consistently
subjects' performance.
The results of this study demonstrate further that a
light pressure (1-2 pounds per square inch) consistently
reduces the amount of jaw opening for those speech tasks
requiring a jaw displacement of more than 10 - 11 mm. These
data were interpreted to suggest that either the sensation
of pressure or pain limits the translatory motion of the
condyle and hence mandibular displacement. Further, these
data suggest that the reduction in range of jaw positions
caused by unilateral intracapsular injection of anesthesia
and unilateral TMJ dysfunction was the result of a mechan¬
ical restriction of condylar translatory motion and not im¬
proved sensation of mandibular position.
Further investigation might explore the clinical
application of pressure to the TMJ of individuals who
demonstrate velopharyngeal incompetency with concomitant
aberrant jaw positioning; specifically adults with bulbar
or flaccid dysarthria. These patients have been observed
to tilt their heads back during speech attempts (Marshall
and Jones, 1971) and to utilize an exaggerated mouth opening
during speech production by this author. It has been
hypothesized that this is a compensatory action to make the

122
oral airway, and not the nasopharyngeal airway, the path of
least resistance. Following successful management of velo-,
pharyngeal incompetency, the use of pressure might prove
beneficial towards returning jaw positioning to more normal
and natural limits if it does not do so spontaneously.
The clinical application of pressure to the TMJ might
be investigated in patients with apraxia of speech. The
patients have been demonstrated to have significantly reduced
abilities on a task of interdental space discrimination
when compared to either normal or aphasic patients (Rosenbek
et al ., 1973). The application of pressure may serve to
enhance mandibular position sense by making patients more
aware of condylar movement.
Since some alterations i r, mandibular posturing and
movement were observed under the experimental conditions and
the acoustic output remained undistorted, it might be sus¬
pected that the other oral articulators compensated to
produce undisrupted speech. Further study of the oral artic¬
ulators, oral air flow, and oral air pressure measures may
provide an understanding of the compensatory adjustments of
the speech articulators. Such information should provide an
insight into the retraining of articulatory patterns.

APPENDIX
Summary of Raw Data and Analysis of Repeated Measures
This Appendix presents a summary of the raw data for
each subject for the two tasks of nonspeech oral movement,
the four tasks of diphthong production, and the four tasks
of vowel-consonant-vowel production. The mean and standard
deviation are presented for each condition. In addition,
a summary of analysis of repeated measures including: sum
of squares, degrees of freedom, mean square, and F statistic
for each tasks is provided. An asterisk (*) following an
F value denotes p<.05.
123

124
Table 23
Elevate Tongue Tip
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
S u b ,i e c t
Normal
Anes thes i a
Pressure
SS
If
MS
F
One:
A
19.76
18.76
13.40
Verti cal
B
3.35
3.02
2.34
Jaw Posi-
C
8.04
8.04
9.38
tion at
D
10.72
13.06
6.70
Tongue
Mean
10.47
10.72
7.96
83.25
2
41 .63
3.906*
Contact
S. D.
3.45
3.37
2.32
(TC)
Two:
A
7.70
9.72
9.72
Hori zontal
B
5.36
5.36
6 . 70
Jaw Posi-
C
4.69
4.36
4.36
tion at TC
D
7.37
7.04
5.70
Mean
6.28
6.62
6.11
2.33
2
1.17
0.779
S.D.
0.74
1.17
1.23
Three:
A
20.77
16.75
12.40
Vertical
B
3.02
1 . 34
0.34
Jaw Posi-
C
8.38
9.76
9.04
tion at
0
11.39
13.74
7.04
Tongue
Mean
10.89
10.38
7.20
142.30
2
71.17
7.078*
Release
S.D.
3.72
3.34
2.54
(TR)
Four:
A
7.37
8.71
9.04
Horizontal
B
5.36
4.69
4.02
Jaw Posi-
C
5.02
4.69
4.69
tion at TR
D
7.70
7.37
5.70
Mean
6.36
6.36
5.86
3.00
2
1 .50
0.877
S.D.
0.68
1 .00
1.11
Five:
A
21 . 78
20.10
13.06
Vertical
B
3.35
3.35
1 .01
Jaw Posi-
C
10.72
14.07
13.40
tion at
D
15.41
14.40
9.72
Lowest
Mean
12.81
12.98
9.29
154.33
2
77.17
5.491*
Tongue (LT)
S.D.
3.88
3.50
2.88

125
Table 23 - continued
Elevate Tongue Tip
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
Six:
A
7.
.70
10.
.05
9.
.38
Horizontal
B
5.
,36
5.
,36
3.
.68
Jaw Posi-
C
5.
. 36
4.
.02
5.
. 36
tion at LT
D
8.
,71
8.
.38
6.
, 70
Mean
6.
,78
6.
,95
6.
.28
4
.33
2
2
.17
0.
,860
S.D.
0.
.85
1 ,
.38
1 .
.20
Seven:
A
2.
.68
1 ,
.34
1 .
.01
Range of
B
0.
.00
0,
.34
1 ,
.34
Vertical
C
2.
.68
6,
.03
4.
.02
Movement
D
4.
.69
1 ,
. 34
3.
.02
from TC
Mean
2.
.51
2,
.26
2.
.34
1 1
CO
o
2
5
.54
0
.453
to LT
S.D.
0.
.96
1
.28
0,
.71
Eight:
A
1 .
.01
1 ,
. 34
1 .
.34
Range of
B
0.
.00
0.
.67
1 .
. 34
Horizontal
C
0.
.00
0.
.67
0,
.34
Movement
D
0.
.34
0.
.00
0,
.34
from TC
Mean
0,
, 34
0,
.67
0.
.84
2
.33
2
1
.17
3.
.621
to LT
S.D.
0.
.24
0
.27
0.
.29
Nine:
A
2.
,68
2,
.01
1.
.34
Range of
B
0.
.67
2.
.01
2,
.34
Vertical
C
0.
.67
1
.68
1
.01
Movement
D
0.
.67
0
. 34
1 .
.01
from TC
Mean
1.
.17
1 .
.51
1 .
.42
1
.08
2
0
.54
0
.330
to TR
S.D.
0.
.50
0.
.40
0.
.32
Ten:
A
1.
.34
1,
.01
1
.01
Range of
B
0.
.00
1
.01
1
.01
Horizontal
C
0.
.67
0
.67
1
.01
Movement
D
0,
.34
0
.34
0.
.34
from TC
Mean
0,
.59
0
. 75
0,
.84
0
. 58
2
0
.29
0
.525
to TR
El even:
A
1.
,01
3
.35
1.
.34
Range of
B
1.
.01
2.
.01
1
.01
Vertical
C
2.
. 34
4,
. 36
4
.36
Movement
D
5 .
.36
1 .
.01
3.
.68
from TR
Mean
2.
.43
2
.68
2,
.60
0
. 58
2
0
.29
0
.037
to LT
S.D.
1 .
.03
0
.74
0.
.84

Measure
Twelve:
Range of
Horizontal
Movement
from TR
to LT
Thirteen:
Time from
TC to LT
Fourteen:
Time from
TC to TR
Fifteen:
Time from
TR to LT
1 26
Table 23 - continued
Elevate Tongue Tip
Condition
Anesthesia/
Subject Norma 1 Anesthesia Pressure
Summary :
Analysis of
Repeated Measures
SS df MS F
A
0.
,67
1 .
,67
1 .
.01
B
0.
.00
1 .
,01
1 .
.01
C
0.
.00
0.
.67
0.
.67
D
2.
.01
1 .
.01
1 .
.01
Mean
0,
.67
1 .
.09
0,
.92
S.
D.
0.
.48
0.
.21
0,
.08
A
6.
, 70
6.
.03
10.
. 39
B
12.
.73
17.
.08
16.
.75
C
11 .
.39
16.
.41
14.
.07
D
24,
.12
28.
.81
24.
.80
Mean
13.
.74
17.
.08
16,
.50
S.
D.
3,
.70
4,
.66
3.
.06
A
4
.69
3.
.02
5,
.02
B
6
.03
11 ,
.06
8,
.71
C
5 .
. 36
9 ,
.72
8,
. 38
D
10.
.72
15.
.41
12,
.06
Mean
6.
.70
9,
.80
8.
.54
S.
D.
1 ,
.37
2.
.57
1 .
.44
A
2.
.01
3.
.02
5.
. 36
B
6.
. 70
6.
.03
8.
.04
C
6
.03
6.
.70
5.
.70
D
13,
.40
13.
.40
12.
.73
Mean
7.
.04
7.
.29
7.
.96
S.
D.
2
.36
2.
.19
1 .
.70
1.58 2 0.79 0.630
114.10 2 57.04 3.893*
86.58 2 43.29 4.485*
8.08 2 4.04 1.177

127
Table 24
Elevate Tongue Dorsum
Condition
Anes thes i a/
Summary:
Analysis
Repeated
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
One:
A
14.07
11.39
12.73
Vertical
B
2.01
-.67
1 .01
Jaw Posi-
C
4.02
5.70
4.36
tion at
D
11.39
8.71
11.39
TC
Mean
7.87
6.28
7.37
23.58
2
S.D.
2.89
2.59
2.81
Two:
A
9.72
9.38
11.01
Horizontal
B
5.70
4.02
4.36
Jaw Posi-
C
7.71
7.04
6.36
tion at
D
10.38
8.38
8.04
TC
Mean
8.38
7.20
7.45
13.58
2
S.D.
1 .06
1.16
1 .42
Three:
A
14.40
11 .06
12.40
Vertical
B
2.01
1.01
0.67
Jaw Posi-
C
4.36
6.70
4.02
tion at
D
12.06
13.60
15.08
TR
Mean
8.38
7.45
8.04
7.75
2
S.D.
3.05
2.71
3.40
Four:
A
10.05
9.72
10.05
Horizontal
B
5.36
3.02
4.02
Jaw Posi-
C
8.04
8.71
7.04
tion at
D
12.40
11.06
10.05
TR
Mean
8.97
8.12
7.79
13.00
2
S.D.
1 .49
1.77
1 .44
Five:
A
18.09
15.41
13.06
Vertical
B
2.68
2.01
1 . 34
Jaw Posi-
C
8.04
7.37
9.04
tion at
D
12.06
10.38
10.72
LT
Mean
10.22
8.79
8.54
29.09
2
S.D.
3.25
2.80
2.54
of
Measures
MS F
.79 2.809
.79 2.900
.88 0.725
.50 2.471
.54 2.678

128
Table 24 - continued
Elevate Tongue Dorsum
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anes thesia
Pressure
SS
df
1
MS
F
Six:
A
7.
.71
9.
,04
9.
38
Horizontal
B
4.
,69
5.
,36
4.
02
daw Posi-
C
8.
,71
6.
. 70
6.
.36
tion at
D
8.
.71
7.
.04
6.
70
LT
Mean
7.
.45
7.
.04
6.
,62
6
.25
2
3
.12
1 .
.333
S.D.
0.
.95
0.
.76
1 .
.10
Seven:
A
4.
.02
4.
.02
3.
.35
Range of
B
0.
.67
2.
. 68
3.
. 35
Vertical
C
4,
.02
1 .
.68
4.
.69
Movement
D
0.
.67
2.
. 34
0.
.67
from TC
Mean
2,
. 34
2,
.68
1 .
.51
19
.00
2
9
.50
1 .
.089
to LT
S.D.
0,
.97
0.
.50
1 .
.06
Eight:
A
2,
.01
1 ,
.68
2,
.01
Range of
B
1 .
. 34
1
. 34
1 .
.01
Horizontal
C
0.
.67
1 .
.68
0.
.67
Movement
D
4
.36
4,
.69
3.
,69
from TC
Mean
2.
.09
2,
.34
1 ,
.84
2
.25
2
1
.12
0,
.474
to LT
S.D.
0,
.80
0,
. 79
0,
.68
Nine:
A
0
.67
0.
.67
0.
.67
Range of
B
0.
.67
1 .
.01
0,
.67
Vertical
C
0,
. 34
2.
.01
1.
.01
Movement
D
2.
.01
5
. 36
4.
.69
from TC
Mean
0,
.92
2.
.26
1 .
.76
16
.33
2
18
.17
2
.026
to TR
S.D.
0
.37
1
.07
0.
.99
Ten:
A
0,
.34
0.
.67
1 .
.34
Range of
B
0,
.67
1 ,
.34
0.
.34
Horizontal
C
1 .
.01
1 ,
.68
0.
.34
Movement
D
2,
.68
4.
.02
2,
.34
from TC
Mean
1 .
.17
1 .
.93
1 .
.09
7
. 58
2
3
. 79
1
. 344
to TR
S.D.
0
.52
0,
. 73
0.
.48
El even:
A
5.
.02
4.
.69
1 .
.01
Range of
B
0
.67
2,
.68
0.
.67
Vertical
C
4
.02
1
. 34
5,
. 70
Movement
D
0,
.67
2.
.68
3,
.68
from TR
Mean
2.
.60
2.
.85
2.
.76
0
. 58
2
0
.29
0
.029
to LT
S.D.
1 .
, 1 3
0.
.69
1 .
.19

129
Table 24 - continued
Elevate Tongue Dorsum
Measure
Condition
Anesthesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis of
Repeated Measures
SS DF MS F
Twelve:
A
2.
,01
1 .
01
Range of
B
1 .
,01
2.
01
Horizontal
C
0.
,67
2.
,01
Movement
D
3.
,68
4.
.02
from TR
Mean
1 .
.84
2.
.26
to LT
S. D.
0.
.68
0.
.63
Thirteen:
A
8,
.04
9.
,38
Time from
B
12,
.73
11 .
,72
TC to LT
C
18,
.50
15.
74
Position
D
22,
,44
24.
.12
Mean
13.
,90
15.
.24
S.D.
3,
.04
3.
.24
Fourteen:
A
2.
.68
4,
.36
Time from
B
6,
.36
5.
. 36
TC to TR
C
5,
. 36
5 ,
.70
Position
D
11 ,
. 39
16.
.42
Mean
6
.45
8.
.02
S.D.
1 ,
.82
2.
.83
Fifteen:
A
5.
.36
5.
.02
Time from
B
6.
.36
6,
.36
TR to LT
C
7
.04
10,
.05
Position
D
11
.06
7,
.71
Mean
7
.45
7,
.29
S.D.
1
.25
1 .
.07
1.01
1 .01
1.34
3.35
1 168 4.08 2 2.04 0.860
0.56
13.74
13.74
15.08
25.12
16.92 81.34 2 40.67 3.177
2.75
5.36
5.70
6.36
17.76
8.80 50.33 2 25.17 2.638
2.99
8.38
8.04
8.71
7.37
8.12 7.00 2 3.50 0.410
0.29

Table 25
Diphthong /a I /
S ummary:
Analysis of
Condi tlon Repeated Measures
Anesthesia/
Measures
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One :
A
14.
. 74
14.
.07
10.
27
Vertical
B
6.
92
4.
02
3.
80
Jaw Posi-
C
9.
.60
12.
73
8.
71
tion for
D
13.
.62
13.
40
10.
.94
Initial
Mean
1 1 .
,22
11 .
.06
8.
,43
1 31
.10
2
65
. 53
15.
326*
Frame
S.D.
1 .
.80
2.
36
1 .
61
Two:
A
4,
.02
5.
.14
5.
.81
Horizontal
B
5 ,
.58
4.
.91
5.
.81
Jaw Posi-
C
5.
.14
5 .
. 36
3.
.57
tion for
D
5.
.81
5.
,81
6.
.48
Initial
Mean
5 .
.14
5.
, 30
5.
.42
1
.06
2
0
.53
0,
.346
Frame
S.D.
0.
.40
0.
.19
0.
.63
Three:
A
12
.95
11 ,
.84
8.
.26
Vertical
B
1 ,
.34
0.
.22
1 ,
.34
Jaw Posi-
C
-0.
.45
-0.
.67
-0.
.22
tion for
D
5
.36
5.
.14
4.
.91
Final
Mean
4
.80
4.
.13
3.
.68
16
.89
2
8
. 44
2
.318
Frame
S.D.
2
.98
2,
.87
1
.82
Four:
A
3
.57
4.
.91
5,
.14
Horizontal
B
4
.69
3.
.57
3.
.80
Jaw Posi-
C
5
. 58
5.
.36
3.
.80
tion for
D
4
.69
3.
.80
4.
.91
Final
Mean
4.
.63
4.
.41
4.
.41
0
.89
2
0
.44
0
.239
Frame
S.D.
0
.41
0,
.43
0.
.36
Five:
A
2
.01
2.
.23
2.
.01
Range of
B
5
.14
3.
.80
2.
.46
Vertical
C
10
.05
13.
.40
8,
.49
Movement
D
8
.26
8.
.49
6,
.03
Mean
6
.36
6,
.98
4.
. 75
71
.17
2
35
.58
10
.014*
S.D.
1 .
, 77
2.
. 52
1 ,
. 54

131
Table 25 - continued
Diphthong /a I/
Measure
Condi tl on
Anesthesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis of
Repeated Measures
SS df MS F
Six:
A
0.67
0.67
Range of
B
1.56
2.68
Horizontal
C
1.12
1.80
Movement
D
1 .56
2.01
Mean
1 .23
1 .79
S.D.
0.21
0.42
Seven:
A
5.80
3.80
T ime
B
4.47
3.57
from
C
5.36
4.91
Initial to
D
5.36
4.91
Final Frame
Mean
5.25
4.30
S.D.
0.28
0.36
0.67
2.01
0.67
1 .80
1 .28 5.056 2 2.53 1.690
0.36
4.69
4.24
5.14
5.36
4.86 12.17 2 6.08 4.813*
0.25

132
Table 26
Diphthong /el/
Summa ry:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
14.29
14.52
10.72
Vertical
B
6.25
4.91
5.81
Jaw Posi-
C
8.26
10.72
8.26
tion for
D
14.07
12.28
10.50
Initial
Mean
10.72
10.61
8.81
60.66
2
30.33
5.945*
Frame
S.D.
2.04
2.05
1.15
Two:
A
4.47
5.58
5.36
Horizontal
B
7.37
5.81
6.92
Jaw Posi-
C
4.24
3.80
2.90
tion for
D
7.15
5.81
6.03
Initial
Mean
5.81
5.25
5.30
5.06
2
2.53
1 .790
Frame
Three:
A
10.94
11.39
7.15
Vertical
B
2.46
1.12
2.68
Jaw Posi-
C
1.79
2.01
2.90
tion for
D
5.36
6.03
4.47
Initial
Mean
5.14
5.14
4.12
12.50
2
6.25
1 .467
Frame
S.D.
2.03
2.34
1.03
Four:
A
2.90
4.47
4.47
Horizonta 1
B
4.24
3.80
5.36
Jaw Posi-
C
3.80
2.90
2.01
tion for
D
4.02
3.80
3.57
Final
Mean
3.74
3.74
3.85
0.22
2
0.11
0.061
Frame
S.D.
0.29
0.32
0.71
Five:
A
3.35
3.13
3.80
Range of
B
3.80
3.80
3.13
Vertical
C
6.92
8.93
5.36
Movement
D
8.71
6.25
6.03
Mean
5.70
5.53
4.58
19.39
2
9.69
1 .903
S.D.
0.80
1 .32
0.67

133
Table 26 - continued
Diphthong /el/
Measure
Condition
Anesthesia/
Sub.ject Normal Anesthesia Pressure
Summary:
Analysis
Repeated
SS df
Six:
A
1 .
.79
1 ,
.12
0.
.89
Range of
B
3.
.35
2.
.23
1 .
.79
Horizonta 1
C
1 ,
.12
1 ,
.56
1 .
.34
Movement
D
3,
.13
2.
.01
2.
.46
Mean
2,
.35
1 .
.73
1 .
.62
S.D.
0,
.53
0.
.25
0,
.33
Seven:
A
6.
,03
3.
,57
4.
.47
Time from
B
4.
.47
4.
.69
4.
.24
Initial
C
6,
.03
5.
.58
5.
.36
to Final
D
6.
,03
4,
.47
6.
.03
Frame
Mean
5.
.64
4.
.58
5.
.02
S.D.
0.
. 39
0.
.41
0,
.41
of
Measures
MS F
.08 3.571*
.58 3.976*

Table 27
Diphthong /aU/
Measure
Subject
Normal
One:
A
16.53
Vertical
B
8.49
Jaw Posi-
C
10.27
tion for
D
16.08
Initial
Mean
12.84
Frame
S.D.
2.03
Two:
A
4.69
Horizontal
B
7.15
Jaw Posi-
C
5.36
tion for
D
7.37
Initial
Mean
6.14
Frame
S.D.
0.66
Three:
A
13.40
Vertical
B
2.46
Jaw Posi-
C
0.00
tion for
D
9.38
Final
Mean
6.31
Frame
S.D.
3.09
Four:
A
4.02
Horizontal
B
5.36
Jaw Posi-
C
5.36
tion for
D
4.91
Final
Mean
4.91
Frame
S.D.
0.32
Five:
A
3.13
Range of
B
6.03
Vertical
C
10.50
Movement
D
6.70
Mean
6.59
S.D.
1 .52
Condition
Anesthesia/
Anesthesia Pressure
16
.08
10
.94
6
.70
5.
.14
13
.18
7.
.82
13.
.40
13.
.40
12
.34
9,
.32
1 .
.99
1 .
.80
6.
.48
6
.25
5
.58
5.
.81
5.
.14
4.
.02
6.
.25
7.
, 1 5
5,
.86
5.
.81
0.
.31
0.
.66
12.
.95
9,
.38
0
.45
2,
.01
-0,
.45
-1 .
. 34
7
.59
8.
. 26
5.
.14
4.
.58
3,
.16
2.
.55
5.
.14
4.
.91
4.
.47
5.
, 36
4.
.69
3.
.80
4,
.24
5.
.58
4.
.63
4.
.91
0.
,19
0.
.40
3,
13
1 .
,79
6.
.48
3.
13
14.
07
9.
.16
5.
81
5 .
14
7.
37
4.
80
2.
35
1 .
61
Summary:
Amalysis of
Repeated Measures
SS df MS F
193.50 2 96.75 15.677*
1.72 2 0.86 0.397
41.72 2 20.86 5.179*
1.39 2 0.69 0.580
92.67 2 46.33 10.884*

135
Table 27 - continued
Diphthong /al)/
Measure
Condition
Anesthesia/
Subject Normal Anesthesia Pressure
Summary:
Analysis
Repeated
SS df
Six:
A
0.
.67
1 .
. 34
1 .
.34
Range of
B
1 .
. 79
1 .
.12
0.
.45
Horizonta 1
C
0.
.67
0.
.67
0.
.89
Movement
D
2.
.46
2,
.23
1 .
.56
Mean
1
.40
1 .
. 34
1 ,
.06
S.D.
0.
.44
0,
. 33
0.
.25
Seven:
A
5
.36
5.
.58
4.
.02
Time from
B
5
.14
5,
.14
4.
.69
Initial
C
8.
.26
8.
.93
8
.49
to Final
D
5.
.81
6.
.70
5,
. 36
Frame
Mean
6,
.14
6.
.59
5.
.64
S.D.
0.
.72
0.
.85
0.
.99
of
Measures
MS F
.86 0.997
.19 1.516

136
Table 28
Diphthong /ol/
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
14.
.07
14.
.74
11 .
,61
Vertical
B
5.
,58
4.
,91
3.
.13
Jaw Posi-
C
5.
,58
7 .
,59
5.
.36
tion for
D
8.
,93
6.
.48
9.
,38
Initial
Mean
8.
,54
8.
43
7.
.37
22,
. 39
2
11
.20
2.
.006
Frame
S.D.
2.
,00
2.
.17
1 .
,92
Two:
A
4.
,24
5.
.81
6,
.92
Horizontal
B
7.
.15
5.
,81
5.
.81
Jaw Posi-
C
6.
.70
5.
,81
5 ,
.58
tion for
D
4.
,02
4.
. 24
5.
.14
Inital
Mean
5,
.53
5.
.42
5.
,86
2
.89
2
1
.44
0,
.751
Frame
S.D.
0,
,81
0.
.39
0,
.38
Three:
A
12,
.51
13,
.18
8.
.93
Vertical
B
2,
.23
1 .
, 79
2.
.23
Jaw Posi-
C
0,
.22
1 .
.34
0.
.00
tion for
D
6,
.25
5.
.14
6.
.92
Final
Mean
5,
.30
5.
. 36
4,
.52
11 .
.72
2
5
.86
1 .
.407
Frame
S.D.
2,
.71
2.
.74
2.
.06
Four:
A
4.
.02
5,
.81
5.
.81
Horizontal
B
5 ,
. 36
5.
.14
4,
.91
Jaw Posi-
C
6,
.25
5.
.14
5,
.36
tion for
D
4
.47
5.
.14
6.
,03
Final
Mean
5,
,02
5 .
.31
5.
.53
3,
.39
2
1
.69
0
.855
Frame
S.D.
0.
.49
0.
. 1 7
0.
.25
Five:
A
1 .
. 79
1 .
.79
2.
.68
Range of
B
3,
.57
3,
.12
1 .
.56
Vertical
C
5.
.58
6 ,
.70
5.
.58
Movement
D
2,
.68
1 ,
.56
2.
.46
Mean
3,
.40
3.
.29
3.
.07
1
.56
2
0
CO
0.
.336
S.D.
0.
.81
1 .
,19
0.
.87

137
Table 28 - continued
Diphthong /ol/
Summary:
Analysis of
Condi ti on Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure
SS
df
MS
F
Six:
A
0.
.89
0,
.89
1 .
.34
Range of
B
2.
.01
0.
.67
0.
.89
Horizontal
C
1 .
.34
1
.12
0.
.89
Movement
D
0.
.89
1 .
.12
1 .
.12
Mean
1
.28
0
.95
1 .
.06
1 . 56
2
0.78
0.
.91 3
S.D.
0.
.26
0,
.10
0.
.10
Seven:
A
4.
.69
4.
.24
3,
.57
Time from
B
4.
.24
3.
.80
4.
.02
Initial
C
5.
.14
5,
.14
4.
.24
to Final
D
4.
.24
4
.02
4.
.02
Frame
Mean
4
.58
4
.30
3,
.96
5.06
2
2.53
2
.588
S.D.
0.
. 21
0
.29
0.
.14

138
Table 29
Vowel-Consonant-Vowel /isi/
Summary:
Analysis of
Condi tl on Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Press ure
SS
df
MS
F
One:
A
2.23
2.01
2.23
Vertical
B
0.22
1.34
0.00
Jaw Posi-
C
4.47
2.68
2.90
tion for
Mean
2.31
2.01
1 .71
3.56
2
1 .78
0.859
V1
S.D.
1 . 23
0.39
0.88
Two:
A
4.69
4.47
5.36
Horizontal
B
4.69
3.80
3.35
Jaw Posi-
C
4.02
2.23
2.68
tion for
Mean
4.47
3.50
3.80
9.85
2
4.93
3.707*
V1
S.D.
0.22
0.66
0.80
Three:
A
-0.67
-1.56
-1.12
Vertical
B
-2.01
-2.01
-1.12
Jaw Posi-
C
0.67
0.45
0.67
tion for
Mean
-0.67
-1.04
-0.52
2.89
2
1 .44
2.364
C
S.D.
0.77
0.76
0.60
Four:
A
2.46
2.46
2.90
Horizontal
B
3.35
3.13
3.13
Jaw Posi-
C
0.89
0.45
0.89
tion for
Mean
2.23
2.01
2.31
0.96
2
0.48
1 .600
C
S.D.
0.72
0.80
0.71
Five:
A
0.67
0.67
1 .79
Vertical
B
0.00
0.67
-0.22
Jaw Posi-
C
3.35
2.01
2.23
tion for
Mean
1 . 34
1.12
1 .27
0.52
2
0.26
0.160
V2
S.D.
1 .02
0.45
0.75
Six:
A
4.02
4.69
4.91
Horizontal
B
4.24
3.35
3.57
Jaw Posi-
C
2.90
2.01
2.68
tion for
Mean
3.72
3.35
3.72
1 .85
2
0.93
1 .428
V?
S.D.
0.41
0.77
0.65

139
Table 29 - continued
Vowel-Consonant-Vowel /isi/
Summary:
Analysis of
Condition Repeated Measures
Anes thesia/
Measure Subject Normal Anes thes i a Pressure SS^ djf MS^ £_
Seven:
A
1.56
1.34
0.89
Range of
B
1.12
2.01
0.22
Vertical
C
1.12
0.67
0.67
Movement
Mean
1.27
1 .34
0.59
3.18
2
1 .59
0.621
from Vi
to V2
S.D.
0.15
0.39
0.20
Eight:
A
2.23
1 .34
1 .79
Range of
B
1 . 34
0.89
0.67
Horizontal
C
3.13
1 .79
2.01
Movement
Mean
2.23
1.34
1 .49
9.18
2
4.59
3.285
from V,
to V2 1
S.D.
0.52
0.26
0.41
Ni ne:
A
2.90
3.57
3.35
Range of
B
2.23
3.35
2.01
Vertical
C
3.80
2.23
2.23
Movement
Mean
2.98
3.05
2.53
2.74
2
1.37
0.515
from V-]
to C
S.D.
0.45
0.41
0.41
Ten:
A
2.23
2.23
2.46
Range of
B
1 .34
0.67
0.45
Horizontal
C
3.13
1.79
2.01
Movement
Mean
2.23
1 .56
1 .64
5.41
2
2.70
2.643
from V-j
to C
S.D.
0.52
0.46
0.61
El even:
A
2.23
3.13
3.13
Range of
B
2.01
2.68
1.12
Vertical
C
2.68
1 .56
2.01
Movement
Mean
2.31
2.46
2.08
1.41
2
0.70
0.493
from C
to V 2
S.D.
0.20
0.46
0.58
Twelve:
A
2.23
2.01
1 .56
Range of
B
1.12
0.67
0.67
Horizontal
C
2.01
1 .56
1.79
Movement
Mean
1 .79
1 .41
1 .34
2.30
2
1.15
1 .984
from C
S.D.
0.34
0.39
0.34
to V2

140
Table 29 - continued
Vowel-Consonant-Vowel /isi/
Summa ry:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure SS
df
MS
F
Thirteen:
A
8.51
9.38
8.71
Time from
B
6.90
7.17
6.50
V-| to V2
C
8.91
6.70
6.50
Mean
8.11
7.75
7.24 8.07
2
4.04
2.081
S.D.
0.61
0.83
0.74
Fourteen:
A
2.90
2.90
2.90
Time from
B
2.68
2.90
4.24
Vt to C
C
2.46
2.23
2.46
Mean
2.68
2.68
3.20 6.89
2
3.44
1 .632
Fifteen :
A
5.58
6.48
5.81
Time from
B
4.24
4.24
2.23
C to V,
C
7.37
4.47
4.02
Mean
5.73
5.06
4.02 29.85
2
14.93
2.843*
S.D.
0.91
0.71
1 .03

141
Table 30
Vowel-Consonant-Vowel /aso./
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Sub.iect
Normal
Anesthesia
Pressure
SS
df
MS
F
One :
A
3.80
3.13
3.80
Vertica1
B
5.58
7.59
7.59
Jaw P o s i -
C
10.05
8.93
7.59
tion for
Mean
6.48
6.55
6.63
0.22
2
0.11
0.017
V1
S.D.
1 .86
1 .75
1 .44
Two:
A
6.03
5.36
6.03
Horizontal
B
5.36
5.58
4.24
Jaw Posi-
C
4.69
4.69
4.91
tion for
Mean
5.36
5.21
5.06
0.89
2
0.44
0.299
V1
S.D.
0.39
0.27
0.52
Three:
A
-2.01
-2.01
-1 .34
Vertical
B
-2.01
-2.01
-2.01
Jaw Posi-
C
1.12
1.12
1.79
tion for
Mean
-0.97
-0.97
-0.52
2.67
2
1 .33
8.000*
C
S.D.
1.04
1 .04
1.17
Four:
A
2.68
2.46
2.90
Horizonta 1
B
3.35
3.35
3.35
Jaw Posi-
C
1.34
0.89
1.34
tion for
Mean
2.46
2.23
2.53
0.96
2
0.48
1 .529
C
S.D.
0.59
0.72
0.61
Five:
A
3.35
2.23
3.13
Vertica1
B
0.00
0.89
1 .56
Jaw Posi-
C
9.16
6.70
6.48
tion for
Mean
4.17
3.27
3.72
8.00
2
4.00
0.483
V2
S.D.
2.68
1 .76
1 .45
Six:
A
6.25
4.91
5.58
Horizontal
B
4.47
5.14
4.47
Jaw Posi-
C
4.47
3.35
4.24
tion for
Mean
5.06
4.47
4 . 76
3.56
2
1.78
1 .524
S.D.
0.59
0.56
0.41

142
Table 30 - continued
Vowel-Consonant-Vowel /asa./
Summary:
Analysis of
Condi ti on Repeated Measures
Anes thesia/
Measure
Sub.iect
Normal
Anes thesia
Pressure
SS
df
MS
F
Seven:
A
0.
.89
1 .
79
0.
.67
Range of
B
5.
58
6.
70
6.
.03
Vertical
C
1 .
.34
2.
23
2.
01
Movement
Mean
2.
,60
3.
57
2.
.90
9.
,56
2
4.
,78
1 .
.085
from V-.
to V2
S.D.
1 .
.49
1 .
57
1 .
.61
Eight:
A
3.
,35
2.
90
3.
35
Range of
B
2.
.46
2.
46
0.
.89
Horizontal
C
3.
.80
4.
24
4.
,02
Movement
Mean
3.
20
3.
,20
2.
.75
2,
.67
2
1
.33
0.
.828
from Vi
S.D.
0.
.39
0.
. 54
0.
.95
to V2
Nine:
A
5.
.81
5.
.14
5.
.14
Range of
B
7,
. 59
9.
.60
9.
.60
Vertical
C
8.
,93
7.
,82
6.
.70
Movement
Mean
7.
.44
7.
,52
7.
,15
1
.56
2
0.
.77
0
.117
from Vi
to C
S.D.
0.
.90
1 .
.30
1 .
.31
Ten:
A
3.
.35
2.
.90
4.
.13
Range of
B
2.
.46
2.
.46
1 .
.12
Horizontal
C
3.
.57
3.
.80
3.
.80
Movement
Mean
3.
.13
3.
.05
2,
.68
2
.30
2
1
.15
1
.078
from Vi
to C
S.D.
0
.34
0.
.39
0.
.80
El even:
A
5,
.58
4,
.47
4.
.47
Range of
B
2
.01
2.
.90
3.
.57
Vertical
C
8
.04
5.
.81
4.
.91
Movement
Mean
5.
.21
4.
.39
4.
. 32
9
.85
2
4
.93
0
.636
from C
S.D.
1 .
.75
0.
.84
0
. 39
to V 2
Twelve:
A
3.
. 57
2.
.46
3,
.13
Range of
B
1
.34
1 .
.79
i.
.34
Horizontal
C
3
.35
3.
.35
2
.90
Movement
Mean
2
.75
2.
.53
2,
.46
0
.96
2
0
.48
0
.581
from C
S.D.
0
.71
0
.45
0.
.56
to V2

143
Table 30 - continued
Vowel-Consonant-Vowel /asa/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure SS
df
MS
F
Thirteen:
A
7.82
7.37
8.04
Time from
B
6.70
6.48
6.25
\l-\ to V2
C
8.04
7.82
8.26
Mean
7.52
7.22
7.52 1.18
2
0.59
1.133
S.D.
0.41
0.39
0.64
Fourteen:
A
2.90
2.90
3.35
Time from
B
2.90
2.90
2.90
V1 to C
C
3.35
4.13
3.80
Mean
3.05
2.98
3.35 1.56
2
0.78
1 .931
S.D.
0.15
0.07
0.26
Fifteen:
A
4.69
4.47
4.69
Time from
B
3.80
3.57
3.35
C to V,
C
4.69
4.69
4.47
Mean
4.47
4.24
4.17 0.96
2
0.48
0.794
S.D.
0.34
0.34
0.41

144
Table 31
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Norma 1
Anesthesia
Pressure
SS
df
MS
F
One:
A
1 .56
2.01
2.90
Vertical
B
3.35
3.57
2.46
Jaw Posi-
C
5.58
5.36
4.91
tion for
Mean
3.50
3.65
3.42
0.52
2
0.26
0.173
h
S.D.
1.16
0.97
0.75
Two:
A
5.36
4.91
5.58
Horizontal
B
3.35
2.46
2.90
Jaw Posi-
C
5.36
4.91
4.69
tion for
Mean
4.69
4.09
4.39
3.56
2
1 .78
1 .730
V1
S.D.
0.67
0.82
0.79
Three:
A
1.12
1.12
2.46
Vertical
B
1 .79
2.68
0.67
Jaw Posi-
C
5.14
5.36
4.69
tion for
Mean
2.68
3.05
2.61
2.30
2
1.15
0.679
C
S.D.
1 .24
1 .24
1.16
Four:
A
5.14
4.69
5.58
Horizontal
B
3.35
2.68
2.46
Jaw Posi-
C
5.58
5.36
5.14
tion for
Mean
4.69
4.24
4.39
2.07
2
1 .04
1 .931
C
S.D.
0.68
0.80
0.97
Five:
A
0.67
1 . 34
2.46
Vertical
B
2.01
2.23
1 . 34
Jaw Posi-
C
5.81
6.03
4.91
tion for
Mean
2.83
3.20
2.90
1 .56
2
0.78
0.629
V2
S.D.
1.54
1 .44
1 .05
Six:
A
5.14
4.69
6.03
Horizontal
B
3.35
2.90
2.68
Jaw Posi-
C
4.69
4.69
4.47
tion for
Mean
4.39
4.09
4.39
1 .18
2
0.59
0.934
S.D.
0.54
0.60
0.97

145
Table 31 - continued
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condi ti on Repeated Measures
Anesthesia/
Measure Subject Normal Anesthesia Pressure £S df MS £
Seven:
A
0.89
0.67
0.45
Range of
B
1.34
1 . 34
1.12
Vertí cal
C
0.22
0.67
0.45
Movement
Mean
0.82
0.89
0.67
0.52
2
0.26
0.336
from V,
to V2
S.D.
0.32
0.22
0.22
Eight:
A
0.22
0.67
0.22
Range of
B
0.22
0.22
0.67
Horizontal
C
0.89
0.67
0.67
Movement
Mean
0.44
0.52
0.52
0.22
2
0.11
0.143
from V-i
to V 2
S.D.
0.22
0.15
0.15
Ni ne :
A
0.89
1.12
0.67
Range of
B
1 .56
1 .34
1 .79
Vertical
C
0.45
0.45
0.22
Movement
Mean
0.97
0.97
0.89
0.07
2
0.04
0.043
from V
to C 1
S.D.
0.32
0.27
0.46
Ten:
A
0.22
0.22
0.00
Range of
B
0.67
0.67
0.89
Horizontal
C
0.22
0.45
0.45
Movement
Mean
0.37
0.47
0.47
0.07
2
0.04
0.084
from Vi
to C
S.D.
0.15
0.13
0.26
Eleven:
A
1.12
0.89
0.67
Range of
B
0.67
0.67
0.45
Vertical
C
1.34
1.79
0.67
Movement
Mean
1 .04
1.12
0.60
3.18
2
1.16
4.649*
from C
to Vj
S.D.
0.20
0.34
0.07
Twelve:
A
0.22
0.45
0.67
Range of
B
0.00
0.45
0.22
Horizontal
C
1.12
0.67
0.67
Movement
Mean
0.45
0.52
0.52
0.07
2
0.04
0.077
from C
S.D.
0.34
0.07
0.15
to V2

146
Table 31 - continued
Vowel-Consonant-Vowel /iki/
Summary:
Analysis of
Condition Repeated Measures
Measure
Subject
Norma 1
Anesthesia
Anesthesia/
Press ure
SS
df
MS
F
Thirteen:
A
8.71
7.82
8.04
Time from
B
7.15
6.92
6.25
V, to V,
C
7.82
7.37
6.92
Mean
7.89
7.37
7.07
6.89
2
3.44
3.221
S.D.
0.45
0.26
0.52
Fourteen:
A
2.90
1.56
2.23
Time from
B
2.68
2.46
2.90
V. to C
C
2.01
1 .79
2.01
Mean
2.53
1 .94
2.38
3.85
2
1 .93
2.144
S.D.
0.27
0.27
0.27
Fifteen:
A
5.81
6.25
5.81
Time from
B
4.47
4.47
3.35
C to V2
C
5.81
5.58
4.91
Mean
5 . 36
5.43
4.69
6.74
2
3.37
3.165
S.D.
0.45
0.52
0.72

147
Table 32
Vowel-Consonant-Vowe 1 /aka/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One:
A
4.47
2.23
4.69
Verti cal
B
8.49
13.40
8.93
Jaw Psoi-
C
10.05
9.60
9.16
tion for
Mean
7.67
8.41
7.59
8.22
2
4.11
0.393
V1
S.D.
1 .66
3.28
1 .45
Two:
A
6.25
4.91
6.25
Horizontal
B
5.36
5.81
4.24
Jaw Posi-
C
5.14
4.91
6.03
tion for
Mean
5.58
5.21
5.51
1. 56
2
0.78
0.444
V1
S.D.
0.34
0.30
0.64
Three:
A
2.01
-0.45
2.23
Vertical
B
3.13
2.01
3.35
Jaw Posi-
C
8.04
7.59
7.59
tion for
Mean
4.39
3.05
4.39
24.00
2
12.00
2.571
C
S.D.
1 .85
2.38
1.63
Four:
A
5.36
3.57
5.81
Horizontal
B
5.81
5.58
4.91
Jaw Posi-
C
5.14
4.91
5.81
tion for
Mean
5.44
4.69
5.51
8.22
2
4.11
1.805
C
S.S.
0.20
0.59
0.30
Five:
A
6.25
2.01
2.46
Vertical
B
3.57
1.12
2.68
Jaw Posi-
C
10.72
8.26
7.82
tion for
Mean
6.85
3.80
4.32
106.90
2
53.44
13.942*
V2
S.D.
2.08
2.25
1 .75
Six:
A
6.48
5.14
6.03
Horizontal
B
5.81
5.58
5.14
Jaw Posi-
C
3.80
4.24
5.36
tion for
Mean
5.36
4.99
5.51
2.89
2
1 .44
1 .253
V2
S.D.
0.80
0.39
0.27

148
Measure
Seven:
Range of
Vertical
Movement
from V]
to V2
Eight:
Range of
Horizontal
Movement
from Vi
to V2
Nine:
Range of
Vertical
Movement
from V,
to C 1
Ten:
Range of
Horizontal
Movement
from V1
to C 1
Eleven:
Range of
Vertical
Movement
from C
to Vj
Twelve:
Range of
Horizontal
Movement
from C
to V2
Table 32 - continued
Vowel-Consonant-Vowel /ak Condition
Anesthesia/
Subject Normal Anesthesia Pressure
Sutnmary:
Analysis of
Repeated Measures
SS df MS F
A
1 .79
0.22
2.23
B
4.91
12.28
"6.25
C
1.12
1 .34
1.34
Mean
2.61
4.61
4.27 148.70 2 74.33 7.894*
S.D.
1.17
3.85
1 .51
A
1 .
. 34
1 .
.34
0.
89
B
0
.67
0.
.89
0.
.45
C
1 ,
.79
1 .
. 34
0.
.89
Mean
1 .
. 27
1 .
.19
0.
,74
2.30 2
1.15 1.600
S.D.
0
.32
0.
.15
0.
.15
A
2.90
2.68
2.46
B
5.36
11 . 39
5.58
C
2.23
2.46
1 .56
Mean
3.50
5.51
3.20
63.19 2 31.59 4.057*
S.D.
0.95
2.94
1 .22
A
1 .
.12
1 .
.34
0.
,45
B
0.
.45
0.
.67
1 ,
.12
C
0.
.89
0.
.89
0.
.45
Mean
0.
.82
0.
.97
0.
.67
0.89 2 0.44 0.821
S.D.
0.
.19
0.
.20
0.
.22
A
4.
.24
2,
.90
1 .
.34
B
0.
, 67
1 ,
.12
0,
.89
C
2.
.90
1 .
.34
0.
.22
Mean
2.
.60
1 .
. 79
0.
.82
32.07 2 16.04 6.887*
S.D.
1 .
.04
0.
.56
0,
.32
A
0.89
1 .56
0.67
B
0.67
0.67
0.22
C
1 .34
0.45
0.67
Mean
0.97
0.89
0.52
2.30 2 1.15 1.459
S.D.
0.20
0.34
0.15

149
Table 32 - continued
Vowel-Consonant-Vowel /aka/
Summary:
Analysis of
Condition Repeated Measures
Anesthesia/
Measure
S u b .i e c t
Normal
Anesthesia
Pressure
SS
df
MS
F
Thirteen:
A
7.59
7.59
7.15
Time from
B
5.81
6.03
5.81
V1 to V2
C
6.48
6.92
6.92
Mean
6.63
6.85
6.63
0.67
2
0.33
0.666
S.D.
0.52
0.45
0.41
Fourteen:
A
2.46
2.23
2.46
Time from
B
2.68
3.35
1 .79
V, to C
C
2.23
3.13
3.13
Mean
2.46
2.90
2.46
2.67
2
1.33
1.524
S.D.
0.13
0.34
0.39
Fifteen:
A
5.14
5.36
4.69
Time from
B
3.13
2.68
4.02
C to V2
C
4.24
3.80
3.80
Mean
4.17
3.95
4.17
0.67
2
0.33
0.381
S.D.
0.58
0.78
0.27

BIBLIOGRAPHY
Abbs, J. A., The influence of the gamma motor system on jaw
movements during speech: A theoretical framework and some
preliminary observations. J. SPEECH HEARING RES., 16:
175-200 (1973).
Abbs, J. A. and Netsell, R., An interpretation of jaw
acceleration during speech as a muscle forcing function,
J. SPEECH HEARING RES., 16: 421-425 (1973),
Abbs, J. A., Netsell, R., and Hixon, T. J., Variations in
mandibular displacement, velocity, and acceleration as a
function of phonetic context. J. ACOUST. SOC. AMER.,
51:89 (1972).
Atkinson, H. F. and Shepherd, R. W., TMJ disturbances and
the associated masticatory patterns. AUST. DENT. 0.,
16: 219-222 (1961).
Bishop, M. E., Ringel, R. L., and House, A. S., Orosensory
perception, speech production, and deafness. J. SPEECH
HEARING RES., 16: 257-266 (1973).
Black, J., The effects of delayed sidetone upon vocal rate
and intensity. J. SPEECH HEARING RES., 16: 56-60 (1951).
Borden, G. J., A phonetic analysis of the speech of four-
year-old boys with mandibular nerve block. A paper
presented at the convention of the American Speech and
Hearing Association (1973).
Cole, R. M., Speech. ASHA REPORTS #6, PATTERNS OF OROFACIAL
GROWTH AND DEVELOPMENT (1971).
Enlow, D. H., The growth and development of the craniofacial
complex. In W. C. Grabb, S. W. Rosenstein, and K. R. Bzoch,
(Eds.) CLEFT LIP AND PALATE, Boston: Little, Brown (1971),
Fairbanks, G., Systematic research in experimental phonetics.
I. A theory of the speech mechanism as a servosystem. J.
SPEECH HEARING DIS., 19: 133-140 (1954).
Fairbanks, G., Selected vocal effects of delayed auditory
feedback. J. SPEECH HEARING DIS., 20: 333-346 (1955).
150

151
Fletcher, S. G., Process and maturation of mastication and
deglutition. ASHA REPORTS #5, SPEECH AND THE DENTOFACIAL
COMPLEX: THE STATE OF THE ART (1970).
Fletcher, S. G., Deglutition. ASHA REPORTS #6, PATTERNS OF
OROFACIAL GROWTH AND DEVELOPMENT (1971).
Fucci, D. J. and Robertson, J. H., Functional defective
articulation: an oral sensory disturbance. PERCEPTUAL
AND MOTOR SKILLS, 33: 711-714 (1971).
Gammon, S. A., Smith, P. J., Daniloff, R. G., and Kim, C. W.,
Articulation and stress/juncture production under oral
anesthesia and masking. J. SPEECH HEARING RES., 14: 271-282
(1971).
Geissler, P. R., A preliminary report on studies of mandibular
movements in speech. DENT. PRACT., 21: 429-432 (1971).
Gibbs, C. H., Reswick, J. B., and Messerman, T., The Case
Gnathic replicator for the investigation of mandibular
movements. Case Institute of Technology, EDC Report no. EDC
4-66-14 (1966).
Gibbs, C. H., Messerman, T., Reswick, J. B., and Derda, H.,
Functional movements of the mandible. J. PROSTH. DENT., 26:
604-620 (1971).
Gibbs, C. H. and Messerman, T., Jaw motion during speech.
ASHA REPORTS #7, OROFACIAL FUNCTION: CLINICAL RESEARCH IN
DENTISTRY AND SPEECH PATHOLOGY (1972).
Gillings, B. R. D., Jaw movements in young adult men during
speech. J. PROSTH. DENT., 29: 567-576 (1973).
Gillings, B. R. D. and Graham, C. H., Photoelectric method
for recording jaw movements. J. DENT. RES., 43: 305 (1964).
Gray, H., ANATOMY OF THE HUMAN BODY, Philadelphia, Pa.: Lea
and Febiger (1959).
Greenfield, B. E. and Wyke, B., Reflex innervation of the
temporomandibular joint. NATURE, 211: 940-941 (1966).
Hansen, G., Effect of jaw restriction on speech intelligi¬
bility. WRIGHT AIR DEVELOPMENT CENTER TECHNICAL REPORT,
52: 223 (1952).
Hixon, T. J. and Hardy, J, C,, Restricted motility of the
speech articulation in cerebral palsy. J, SPEECH HEARING
DIS. , 29; 293-306 ( 1 964) ,
Horii, Y., House, A. S., Li, K. P,, and Ringel, R., Acoustic
characteristics of speech produced without oral sensation.
J. ACOUST. SOC. AMER. , 51: 1 06-1 28 (1 972).

152
Ingervall, B., Bratt, C. M,, Carlsson, G, E., Helkimo, M.,
and Lantz, B., Positions and movements of the mandibular
and hyoid bone during swallowing. A ci neradiographic study
of swallowing with and without anesthesia of the TMJ's.
ACTA ODONT. SCAND., 29: 549-562 0971).
Ingervall, B., Bratt, C. M., Carlsson, G. E., Helkimo, M. ,
and Lantz, B., Duration of swallowing with and without
anesthesia fo the temporomandibular joints. SCAND. J. DENT,
RES. , 80: 189-196 [1 972) ,
Jankelson, B., Hoffman, G. M., and Hendron, J. A., The
physiology of the stomatagnathic system. J. AMER, DENT.
ASSN., 46: 375-386 (1953).
Kawamura, Y., Neuromuscular mechanism of jaw and tongue
movement. J. AMER. DENT. ASSN., 65: 545-551 (1961).
Kawamura, Y. and Watanabe, M., Studies on oral sensory
threshold. MEDICAL J. OF OSAKA UNIVERSITY, 10: 291-301 (1960).
Kent, R. D., Some considerations in the cinef1uorographic
analysis of the tongue movements during speech. PHONETICS,
26: 16-32 (1972).
Kent, R. D., Is the seriation of speech movements governed by
motor programs or feedback? A paper presented at the annual
convention of the American Speech and Hearing Association,
Detroit, Michigan (1973).
Kent, R. and Moll, K. , Cinefluorographic analysis of selected
lingual consonants. J. SPEECH HEARING RES., 15: 453-473
(1 972) .
Keppel , G., DESIGN AND ANALYSIS, Englewood Cliffs, New Jersey:
Prentice-Hall, Inc. (1973).
Larsson, L. E. and Thilander, B., Mandibular positioning:
the effect of pressure on the joint capsule. OCTA NEUROL.
SCAND., 40: 131-143 ( 1964) .
Lee, B. S., Effects of delayed speech feedback. J. ACOUST.
SOC. AMER., 22: 824-826 (1950).
MacNeilage, P. F., Closed-loop control of the iniatiation of
jaw movements for speech. A paper presented at the annual
convention of the Accoustical Society of America (1970).
Mahan, P. E., Anatomy of the stomatagnathic system. In S, D,
Tylman (Ed.) THEORY AND PRACTICE OF CROWN AND FIXED PARTIAL
PROSTHODONTICS (BRIDGE), St. Louis, Mo: C. V. Mosby (1967).

153
Manly, R. S., Pfaffman, C., Lathrop, D. D., and Keyser, J.,
Oral sensory thresholds of persons with natural and arti¬
ficial dentitions. J. DENT. RES., 31 : 305-31 2 Cl 952 ) .
Marshall, R. C. and Jones, R. N,, Effects of a palatal lift
prosthesis upon the intelligibility of a dysarthic patient.
J. PROSTH. DENT., 25: 327-332 (1971).
McCroskey, R. L., The relative contribution of auditory
and tactile cues to certain aspects of speech. SOUTHERN
SPEECH JOURNAL, 24: 84-90 (1958).
McCroskey, R. C., Corley, N. W., and Jackson, G., Some effects
of disrupted tactile cues upon the production of consonants.
SOUTHERN SPEECH JOURNAL, 25: 55-60 (1959).
McNutt, J. C., Oral sensation and motor abilities of /s/ de¬
fective /r/ defective and normal speaking junior high
school students. A paper presented at the annual convention
of the American Speech and Hearing Association, Detroit,
Michigan (1973).
Moser, H., LaGourgue, J. R,, and Class, L., Studies of oral
stereognosis in normal, blind, and deaf subjects. In J. F.
Bosma (Ed.) SYMPOSIUM ON ORAL SENSATION AND PERCEPTION,
Springfield, Illinois: Charles C Thomas (1967).
Mountcastle, V. B. and Powell, P., Central nervous mechanisms
subserving position sense and kinesthesis. BULLETIN: JOHN
HOPKINS HOSPITAL, 105: 173-200 (1959).
Moyers, R. C., HANDBOOK OF ORTHODONTICS, Chicago: Yearbook
Medical Publishers (1973).
Owens, D. E., A cinefluorographic study of horizontal and
vertical mandibular movement patterns for normal speakers.
Master's Thesis, University of Florida (1973).
Perry, C., Neuromuscular control of mandibular movements.
J. PROSTH. DENT., 30: 714-720 (1973).
Posselt, U. and Thilander, B., Influence of the innervation
of the temporomandibular joint capsule on mandibular bor¬
der movements. OCTA ODONT. SCAND., 23: 601-613 (1965).
Putnam, A. H. B. and Ringel, R. L,, Some observations of
articulation during labial sensory deprivation, J, SPEECH
HEARING RES., 15: 529-542 (1972),
Ransjo, K. and Thilander, B,, Perception of mandibular posi¬
tion in cases of temporomandibular joint disorders.
0D0NT0L. FOREN. TIDSKR,, 11: 134-144 (1963).

154
Ricketts, R. M., Roentgenography of the temporomandibular
joint. In B. G. Sarnat (Ed.), THE TEMPOROMANDIBULAR JOINT,
Springfield, Illinois: Charles C Thomas (1964),
Ringel, R. L., Burk, K. W., and Scott, S. M., Tactile Percep¬
tion: form discrimination in the mouth. BRIT. J. DIS.
COMMUN., 3: 150-155 (1968).
Ringel, R. L., Saxman, J. H,, and Brooks, A. R., Oral Percep¬
tion: II mandibular kinesthesia, J. SPEECH HEARING RES.,
10: 637-641 (1967).
Ringel, R. L. and Steer, M. 0., Some effects of tactile and
auditory alterations on speech output. J. SPEECH HEARING
RES., 6: 369-378 (1963).
Rose, J. E. and Mountcastle, V., Touch and kinesthesia. In
J. Field (Ed.), HANDBOOK OF PHYSIOLOGY, Section 1, Vol . 1,
American Physiology Society (1959).
Rosenbek, J. C., Wertz, R. T., and Darley, F. L., Oral sen¬
sation and perception in apraxia of speech and aphasia.
J. SPEECH HEARING RES., 16: 22-36 (1973).
Sarnat, B. G., THE TEMPOROMANDIBULAR JOINT, Springfield,
Illinois: Charles C Thomas (1964).
Schaerer, P., Legault, J. V., and Zander, H. A., Mastication
under anesthesia, HELV. ODONT. ACTO., 10: 130 (1966).
Schliesser, H. F. and Coleman, R. 0., Effectiveness of cer¬
tain procedures for alteration of auditory and oral tactile
sensation for speech. PERCEPT. MOTOR SKILLS, 26: 275-281
(1968) .
Scott, C. M. and Ringel, R. L. , Articulation without oral
sensory control, J, SPEECH HEARING RES., 14: 804-818 (1971a).
Scott, C. M. and Ringel, R. L., The effects of motor and
sensory disruptions on speech: A description of articula¬
tion. J. SPEECH HEARING RES., 14: 819-828 (1971b).
Shepherd, R. W., A further report on mandibular movement.
AUST. DENT. J., 5: 337-342 (I960).
Sicher, H. and DuBrul, E., ORAL ANATOMY, St. Louis: C. V.
Mosby (1970).
Siirila, H. S. and Laine, P,, The tactile sensibility of the
peridontium to slight axial loadings of the teeth, ACTA
ODONT. SCAND, , 21 : 41 5 (1 963),

155
Siirila, H. S. and Laine, P., Sensory thresholds in discrim¬
inating differences in thickness between the teeth, by
different degrees of mouth opening. PROG. FINN. DENT. SOC.,
68: 134-139 (1972).
Storey, A. T., Sensory functions of the temporomandibular
joint. J. CAÑAD. DENT. ASSN., 34: 294-30Q (1968),
Sussman, H. M. and Smith, K. U,, Transducer for measuring
mandibular movements, J. ACOUST. SOC. AMER., 48; 857-858
( 1 970).
Sussman, H. M. and Smith, K. U,, Jaw movements under delayed
auditory feedback. J. ACOUST. SOC. AMER., 50: 685-691 (1971).
Sussman, H. M. , MacNeilage, P. F., and Hanson, R. J., Labial
and mandibular dynamics during the production of bilabial
consonants: preliminary observations. J. SPEECH HEARING
RES., 16: 397-420 (1973).
Thilander, B., INNERVATION OF THE TEMPOROMANDIBULAR JOINT
CAPSULE IN MAN. Almquist and Niksells, Uppsala, Sweden:
Almquist and Niksells (1961).
Thompson, R. C., The effects of oral sensory disruption upon
oral stereognosis and articulation. A paper presented at
the annual convention of the American Speech and Hearing
Association, New York (1969).
Weinberg, B., Liss, G. M., and Hillis, J. A., A comparative
study of visual, manual, and oral form identification in
speech impaired and normal speaking children. In J. F.
Bosma (Ed.) SECOND SYMPOSIUM ON ORAL SENSATION AND PERCEP¬
TION, Springfield, Illinois: Charles C Thomas (1970).
Weiss, C. E., The effects of disrupted 1ingual-palatal taction
on articulation. J. OF COMM. DIS., 2: 14-19 (1969a).
Weiss, C. E., The effects of disrupted 1ingual-palatal taction
on physiologic parameters of articulation. J. OF COMM. DIS.,
2: 312-321 (1969b).
Williams, W. N. and LaPointe, L.L., Relationships among oral
form recognition, interdental thickness discrimination, and
interdental weight discrimination. PERCEPT. MOTOR SKILLS,
35: 191-194 (1972).
Williams, W, N. and LaPointe, L,L,, and Thornby, J. I., Inter¬
dental thickness discrimination by normal subjects. J, OF
DENT. RES,, (1974),
Wise, A., APPLIED PHONETICS, New York: Appleton-Century-
Crofts (1957).

156
Woodford, L. D., Oral Stereognosis. Master's Thesis,
University of Illinois (1964).
Zemlin, W.R., SPEECH AND HEARING SCIENCE, Englewood Cliffs,
New Jersey: Prentice-Hall (1968).

BIOGRAPHICAL SKETCH
The author was born in Chicago, Illinois on June 19,
1948. He moved with his family to Tampa, Florida, at the age
of four. In Tampa, he attended grammar school and high school.
In 1966, he enrolled at the University of South Florida (USF)
in Tampa and in 1970 he completed the requirements for a
Bachelor of Arts degree in Speech Science. Subsequently, he
was accepted into the Master's program at USF in Speech
Pathology and completed a six month internship at the Mailman
Center for Child Development in Miami, Florida. A Master of
Science degree was awarded in 1971. The author was accepted,
susequently, into the Doctoral progran in Speech Pathology
at the University of Florida, Gainesville, Florida. While
at the University of Florida, the author gained experience
as a research assistant, teaching assistant, and as a Speech
Pathology intern at the Veterans Administration Hospital in
Gainesville, Florida. In 1973, he was awarded a summer
internship to the University of Oregon Dental School by the
Joint Committee on Dentistry and Speech Pathology-Audiology.
The author is currently employed as a Research Speech Patholo¬
gist at the H.K. Cooper Institute for Oral-Facial Anomolies
and Communicative Disorders in Lancaster, Pennsylvania.
157

I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Philosophy.
Edward C. Hutchinson, Chairman
Associate Professor of Speech
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Philosophy.
William N. Williams, Cochairman
Associate Professor of Speech
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality,
as a dissertation for the degree of Doctor of Pin 1 osophy.
Leonard L. LaPointe
Assistant Professor of Speech

I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality
as a dissertation for the degree gi—Bs-cJmr of Philosophy.
Parker E. Mahan
Professor of Dentistry
This dissertation was submitted to the Graduate Faculty
of the Department of Speech in the College of Arts and
Sciences and to the Graduate Council, and was accepted as
partial fulfillment of the requirements for the degree of
Doctor of Philosophy.
August, 1976
Dean, Graduate School

UNIVERSITY OF FLORIDA
3 1262 08554 7163



ACKNOWLEDGEMENTS
The author wishes to extend his sincerest gratitude
to his committee members, Drs. Ed Hutchinson, Bill Williams
Chick LaPointe, and Parker Mahan, Throughout the project
they provided continued encouragement and assistance.
Acknowledgement is extended also to Dr. Joe Meier and
Mr. Harry Canter of Millersville State College, Millersvill
Pennsylvania and to Dr. Paul Ross, Franklin and Marshall
College, Lancaster, Pennsylvania. These gentlemen were
instrumental in completing the statistical analysis of the
data.
Finally, the author wishes to acknowledge the assist
ance of Linda McCullers, who aided in all stages of the
study. It is to Linda that this study is dedicated.


49
instrumentation was developed by Williams and LaPointe (1972)
and uses 21 capsules ranging in weight from 5 to 25 grams.
This task required each subject to make judgements between
pairs of weighted capsules which were presented, one at a time
between the maxillary and the mandibular central incisors.
Each subject was asked to judge whether the second of each
pair of capsules was "the same," "heavier," or "lighter" than
the first capsule. The first capsule was always the "standard
weight of 5 grams. The second capsule of each pair was always
heavier than the first. A modified "method of limits," with
two ascending runs, was used to arrive at each subject's
difference limen. A "run" was defined as for the previous
perceptual tasks.
Nonspeech Oral Movements
Tasks of nonspeech oral movement were included in the
study since evidence suggests that the neurological process
governing speech and nonspeech oral movements are dissimilar.
Hixon and Hardy (1964) suggested that speech movements may be
the result of automatic, programmed motor patterns, while less
practiced nonspeech oral movements, such as repetitive raising
the tongue to and dropping it from the alveolar ridge, would
require voluntary, concentrated motor movements.
Two nonspeech oral movements were used on this study to
examine the role of the sensory mechanism of the TMJ for
regulating mandibular movement and positioning for nonspeech
activities. These tasks required each subject to: 1) elevate
the tongue tip up against the alveolar ridge and to drop it


128
Table 24 continued
Elevate Tongue Dorsum
Summary:
Analysis of
Condi tion Repeated Measures
Anesthesia/
Measure
Subject
Normal
Anes thesia
Pressure
SS
df
1
MS
F
Six:
A
7.
.71
9.
,04
9.
38
Horizontal
B
4.
,69
5.
,36
4.
02
daw Posi-
C
8.
,71
6.
. 70
6.
.36
tion at
D
8.
.71
7.
.04
6.
70
LT
Mean
7.
.45
7.
.04
6.
,62
6
.25
2
3
.12
1 .
.333
S.D.
0.
.95
0.
.76
1 .
.10
Seven:
A
4.
.02
4.
.02
3.
.35
Range of
B
0.
.67
2.
. 68
3.
. 35
Vertical
C
4,
.02
1 .
.68
4.
.69
Movement
D
0.
.67
2.
. 34
0.
.67
from TC
Mean
2,
. 34
2,
.68
1 .
.51
19
.00
2
9
.50
1 .
.089
to LT
S.D.
0,
.97
0.
.50
1 .
.06
Eight:
A
2,
.01
1 ,
.68
2,
.01
Range of
B
1 .
. 34
1
. 34
1 .
.01
Horizontal
C
0.
.67
1 .
.68
0.
.67
Movement
D
4
.36
4,
.69
3.
,69
from TC
Mean
2.
.09
2,
.34
1 ,
.84
2
LT)
C\J
2
1
.12
0,
.474
to LT
S.D.
0,
.80
0,
. 79
0.
.68
Nine:
A
0
.67
0.
.67
0.
.67
Range of
B
0.
.67
1 .
.01
0,
.67
Vertical
C
0,
. 34
2.
.01
1.
.01
Movement
D
2.
.01
5
. 36
4.
.69
from TC
Mean
0,
.92
2.
.26
1 .
.76
16
.33
2
18
.17
2
.026
to TR
S.D.
0
.37
1
.07
0.
.99
Ten:
A
0,
.34
0.
.67
1 .
.34
Range of
B
0,
.67
1 ,
.34
0.
.34
Horizontal
C
1 .
.01
1 ,
.68
0.
.34
Movement
D
2,
.68
4.
.02
2,
.34
from TC
Mean
1 .
.17
1 .
.93
1 .
.09
7
. 58
2
3
. 79
1
. 344
to TR
S.D.
0.
.52
0,
. 73
0.
.48
El even:
A
5.
.02
4.
.69
1 .
.01
Range of
B
0,
.67
2,
.68
0.
.67
Vertical
C
4
.02
1
. 34
5,
. 70
Movement
D
0,
.67
2,
.68
3,
.68
from TR
Mean
2.
.60
2.
.85
2.
.76
0
. 58
2
0
.29
0
.029
to LT
S.D.
1 .
, 1 3
0.
.69
1 .
.19


148
Measure
Seven:
Range of
Vertical
Movement
from V]
to V2
Eight:
Range of
Horizontal
Movement
from Vi
to V2
Nine:
Range of
Vertical
Movement
from V,
to C 1
Ten:
Range of
Horizontal
Movement
from V1
to C 1
Eleven:
Range of
Vertical
Movement
from C
to Vj
Twelve:
Range of
Horizontal
Movement
from C
to V2
Table 32 continued
Vowel-Consonant-Vowel /ak Condition
Anesthesia/
Subject Normal Anesthesia Pressure
Sutnmary:
Analysis of
Repeated Measures
SS df MS F
A
1 79
0.22
2.23
B
4.91
12.28
"6.25
C
1.12
1 .34
1.34
Mean
2.61
4.61
4.27 148.70 2 74.33 7.894*
S.D.
1.17
3.85
1.51
A
1 .
. 34
1 .
.34
0.
89
B
0
.67
0.
.89
0.
.45
C
1 ,
.79
1 .
. 34
0.
.89
Mean
1 .
. 27
1 .
.19
0.
,74
2.30 2
1.15 1.600
S.D.
0
.32
0.
.15
0.
.15
A
2.90
2.68
2.46
B
5.36
11 39
5.58
C
2.23
2.46
1 .56
Mean
3.50
5.51
3.20
63.19 2 31.59 4.057*
S.D.
0.95
2.94
1 .22
A
1 .
.12
1 .
.34
0.
,45
B
0.
.45
0.
.67
1 ,
.12
C
0.
.89
0.
.89
0.
.45
Mean
0.
.82
0.
.97
0.
.67
0.89 2 0.44 0.821
S.D.
0.
.19
0.
.20
0.
.22
A
4.
.24
2,
.90
1 .
.34
B
0.
, 67
1 ,
.12
0,
.89
C
2.
.90
1 .
.34
0.
.22
Mean
2.
.60
1 .
. 79
0.
.82
32.07 2 16.04 6.887*
S.D.
1 .
.04
0.
.56
0,
.32
A
0.89
1 .56
0.67
B
0.67
0.67
0.22
C
1 .34
0.45
0.67
Mean
0.97
0.89
0.52
2.30 2 1.15 1.459
S.D.
0.20
0.34
0.15


Table 25
Diphthong /a I /
S ummary:
Analysis of
Condi tlon Repeated Measures
Anesthesia/
Measures
Subject
Normal
Anesthesia
Pressure
SS
df
MS
F
One :
A
14.
. 74
14.
.07
10.
27
Vertical
B
6.
92
4.
02
3.
80
Jaw Posi-
C
9.
.60
12.
73
8.
71
tion for
D
13.
.62
13.
40
10.
.94
Initial
Mean
1 1 .
,22
11 .
.06
8.
,43
1 31
.10
2
65
. 53
15.
326*
Frame
S.D.
1 .
.80
2.
36
1 .
61
Two:
A
4,
.02
5.
.14
5.
.81
Horizontal
B
5 ,
.58
4.
.91
5.
.81
Jaw Posi-
C
5.
.14
5 .
. 36
3.
.57
tion for
D
5.
.81
5.
,81
6.
.48
Initial
Mean
5 .
.14
5.
, 30
5.
.42
1
.06
2
0
.53
0,
.346
Frame
S.D.
0.
.40
0.
.19
0.
.63
Three:
A
12
.95
11 ,
.84
8.
.26
Vertical
B
1 ,
.34
0.
.22
1 ,
.34
Jaw Posi-
C
-0.
.45
-0.
.67
-0.
.22
tion for
D
5
.36
5.
.14
4.
.91
Final
Mean
4
.80
4.
.13
3.
.68
16
.89
2
8
. 44
2
.318
Frame
S.D.
2
.98
2,
.87
1
.82
Four:
A
3
.57
4.
.91
5,
.14
Horizontal
B
4
.69
3.
.57
3.
.80
Jaw Posi-
C
5
. 58
5.
.36
3.
.80
tion for
D
4
.69
3.
.80
4.
.91
Final
Mean
4.
.63
4.
.41
4.
.41
0
.89
2
0
.44
0
.239
Frame
S.D.
0
.41
0,
.43
0.
.36
Five:
A
2
.01
2.
.23
2.
.01
Range of
B
5
.14
3.
.80
2.
.46
Vertical
C
10
.05
13.
.40
8,
.49
Movement
D
8
.26
8.
.49
6,
.03
Mean
6
.36
6,
.98
4.
. 75
71
.17
2
35
.58
10
.014*
S.D.
1 .
, 77
2.
.52
1 ,
. 54


Te Te Te
10
Muscles of Mastication
Suprahyoid Muscles
M:
Masseter
Mh:
Mylohyoid
Te:
T emporalis
Gh:
Geniohyoid
EPy:
External Pterygoid
Da b:
Anterior Belly
of Digastric
IPy:
Internal Pterygoid
Figure 3
Muscular Control of Mandibular Movement
After Cole (1971)