Temporomandibular Joint

Question 1

muscle activation + joint motion =

Answer 1

joint loading

Question 2

How is the position of the TMJ joint maintained?

Answer 2

position maintained by: muscles, ligaments, and the TM joint capsule

Question 3

M-L length is __x that of the A-P

Answer 3

2X

Question 4

Where is the TMJ palpated?

Answer 4

Palpated at the lateral pole just anterior to the external auditory meatus

Question 5

What are the 2 joint surfaces covered by?

Answer 5

fibrocartilage

Question 6

The articular surface are both ________ ( –>incongrutent joint)

Answer 6

convex

Question 7

What is the articular disc interposed between?

Answer 7

the joint surfaces

Question 8

The inferior TM joint cavity is made up of the:

Answer 8

mandibular condyle and inferior surface of the disc

Question 9

The inferior TM joint cavity is considered a _______ joint.

Answer 9

hinge

Question 10

The superior TM joint cavity is made up of the:

Answer 10

articular eminence and superior surface of the disc

Question 11

The superior TM joint cavity is considered a _____ joint.

Answer 11

gliding

Question 12

What are three properties of the articular disc?

Answer 12

1) bi-concave fibrocartilage disc
2) avascular and insensate
3) thin in the central portion and thickens anterior and posterior

Question 13

Name 5 functions of the articular disc:

Answer 13

1) congruency for joint articulations
2) stability
3) minimizes loss of mobility
4) reduces friction
5) decreases stress on the TMJ

Question 14

Is the lateral ligament of the TMJ complex the primary or secondary ligament?

Answer 14

primary

Question 15

What function does the lateral ligament serve?

Answer 15

stabilizes the lateral aspect of the capsule
and
guides the condylar movement during mouth opening

Question 16

What is normal ROM for depression and elevation

Answer 16

40-50mm

Question 17

What is normal ROM for lateral deviation?

Answer 17

10-12 mm

Question 18

What is normal ROM for protrusion

Answer 18

6-9mm

Question 19

What is normal ROM for retrusion

Answer 19

3mm

Question 20

What muscles aid in depression?

Answer 20

suprahyoids and lateral pterygoind (inferior head)

Question 21

What muscles aid in elevation?

Answer 21

temporalis, masseter, medial pterygoid

Question 22

What muscles aid in lateral deviation?

Answer 22

medial & lateral pterygoid to opposite side (contralateral movement) and temporalis to same side (ipsilateral)

Question 23

What muscles aid in retrusion?

Answer 23

bilateral temporalis and suprahyoids

Question 24

What is the depression/ opening of the mouth responsible for?

Answer 24

key for may functional activities

Question 25

What is the elevation/ closing of the mouth responsible for?

Answer 25

essential for grinding food

Question 26

What is the lateral deviation of the mouth responsible for?

Answer 26

- side to side translation | - grinding motion associated with chewing

Question 27

What is the protrusion of the mouth responsible for?

Answer 27

(Mandible translates anteriorly) | Integral aspect of maximal opening of mouth

Question 28

What is the retrusion of the mouth responsible for?

Answer 28

(madible translates posteriorly) | Essential for functional activities

Question 29

The first 11* of arthrokinematic motion of the TMJ includes ______?

Answer 29

rotation | The condyle rolls relative to the inferior surface of the disc in the inferior joint

Question 30

True or false? The translation of the condyle and disc along the articular eminence in the superior joint normal should occur together?

Answer 30

True

Question 31

There is a _:_ ratio opening to lateral deviation and protrustion

Answer 31

4:1

Question 32

During early phase of opening the ROM is _____ and the body of the mandible moves ______ and _______.

Answer 32

ROM is 35-50% | mandible moves posteriorly and inferior

Question 33

During late phase of opening the final ___% of ROM occurs.

Answer 33

50%

Question 34

During late phase of opening, movement occurs from ________ to translatory motion.

Answer 34

rotation

Question 35

During late phase of opening the condyle and disc move together ______ and _______.

Answer 35

forward and inferior

Question 36

During late phase of opening what kind of maximal stretch on the disc occurs?

Answer 36

maximal anterior stretch

Question 37

During closing tension from where retracts the disc?

Answer 37

Tension from the retrodiscal lamina

Question 38

Which occurs first and last: rotation or translation?

Answer 38

Translation - first | Rotation - last

Question 39

Is neck function an integral part of natural jaw behavior?

Answer 39

Yes

Question 40

What is TMD?

Answer 40

A collection of symptoms that involve the TMJ and surrounding structures (facial muscles, ligaments, teeth, ears, neck, etc).

Question 41

What symptoms are included in TMD?

Answer 41

``` TMJ, face, ear, muslce, neck pain Tinnitus (ringing in the ears) Dizziness Headache Joint sounds (popping, clicking or grinding) Limited mandibular ROM ```

Question 42

What can results in loss of tissue function and damage to the TMJ?

Answer 42

Unresolved and chronic inflammation

Question 43

What types of unresolved and chronic inflammation diseases may cause TMJ disfunction?

Answer 43

RA, other autoimmune disorders, trauma to the face/ TM joint, long periods of immobilization