TMJ

Question 1

What is the shape of the articular disc of the TMJ?

Answer 1

Bi-concave

Question 2

Is the articular disc mainly vascular or avascular?

Answer 2

Avascular

Question 3

Is the peripheral aspect of the articular disc vascular or avascular?

Answer 3

Vascular

Question 4

What are the 3 divisions of the articular disc?

Answer 4

Anterior
Intermediate
Posterior

Question 5

The articular disc sits where in relation to the condyle?

Answer 5

On top of the condyle

Question 6

What are the 2 joint cavities of the TMJ?

Answer 6

Superior joint cavity

Inferior joint cavity

Question 7

Where is the inferior joint cavity located?

Answer 7

Between the mandibular condyle and the inferior surface of the articular disc

Question 8

Where is the superior joint cavity located?

Answer 8

Between the superior surface of the articular disc and the mandibular fossa

Question 9

What type of joint is the superior joint cavity?

Answer 9

Gliding

Question 10

What type of joint is the inferior joint cavity?

Answer 10

Hinge

Question 11

What is the primary motion during the initial phase of jaw opening?

Answer 11

Rotation

Question 12

What is the primary motion during the late phase of jaw opening?

Answer 12

Translation

Question 13

Do the lateral and medial pterygoids muscles produce contralateral or ipsilateral motion of the jaw?

Answer 13

Contralateral

Question 14

Do the masseter and temporalis muscles produce contralateral or ipsilateral motion of the jaw?

Answer 14

Ipsilateral

Question 15

What are the arthrokinematics of the mandibular condyle during rotation?

Answer 15

Mandibular condyle rolls relative to the inferior surface of the disc

Question 16

What are the arthrokinematics of the mandibular condyle during translation?

Answer 16

Mandibular condyle and articular disc slide together

Question 17

Describe the 4 main roles of the articular disc of the TMJ

Answer 17

1. Adds concavity to the joint
2. Improves mobility of the joint
3. Stabilizes the joint
4. Reduces friction in the joint

Question 18

What type of joint is the TMJ?

Answer 18

Diarthrodal synovical

Question 19

Does TMD affect more females or males?

Answer 19

Females

Question 20

What muscles depress the mandible? (3)

Answer 20

Inferior fibers of lateral pterygoid
Suprahyoids
Infrahyoids

Question 21

What muscles elevate the mandible? (3)

Answer 21

Temporalis
Masseter
Medial pterygoid

Question 22

What muscles laterally deviate the mandible? (4)

Answer 22

Temporalis and masseter (ipsilateral)

Medial and lateral pterygoid (contralateral)

Question 23

What muscles protrude the mandible? (3)

Answer 23

Masseter

Medial and lateral pterygoids

Question 24

What muscles retrude the mandible? (3)

Answer 24

Deep fibers of masseter
Temporalis
Suprahyoids

Question 25

What are the 3 ligaments of the TMJ?

Answer 25

Temporomandibular
Stylomandibular
Sphenomandibular

Question 26

Is there more stability in the medial/lateral aspect of the TMJ or the anterior/posterior aspect?

Answer 26

Medial/lateral

Question 27

Is there more mobility in the medial/lateral aspect of the TMJ or the anterior/posterior aspect?

Answer 27

Anterior/posterior

Question 28

What is another name for the temporomandibular ligament?

Answer 28

Lateral ligament

Question 29

What motion do the superficial oblique fibers of the lateral ligament limit?

Answer 29

Rotation of condylar head

Question 30

What motion do the deep fibers of the lateral ligament limit?

Answer 30

Posterior displacement of condylar head

Question 31

What motion do the stylomandibular and sphenomandibular ligaments limit?

Answer 31

Excessive protrusion of the mandible