TMJ (p. 294)

Question 1

What is the function of the temporomandibular ligament?

Answer 1

• prevent the condyle from being displace too far inferiorly and posteriorly
• provide some resistance to lateral displacement

Question 2

What are the two types of movement of the TMJ?

Answer 2

Hinge/rotating and gliding/sliding (translation)

Question 3

What is the first phase of the hinge rotation action?

Answer 3

Mouth opening approx. first 2 cm

Question 4

What happens after the mouth opening in the hinge/rotating action?

Answer 4

• Posterior lamina prevents the disc from moving anterior with the condyle
• Disc and condyle rotate one another

Question 5

What is the second phase in opening the mouth?

Answer 5

Gliding or sliding, aka translation

Question 6

Describe the 5 steps of translation

Answer 6

1. Rotational motion continues
2. Gliding occurs anteriorly
3. Disc slides along the posterior slope of the articular eminence
4. Caused by the inferior head of the lateral pterygoid muscle
5. Condyle and disc move forward until they reach a point just slightly posterior to the crest of the articular eminence