Biomechanics TMJ Features

Question 1

What type of joint is the TMJ

Answer 1

Ginglyoarthrodial and Hinge Joint

Question 2

How many compartments does the TMJ have

Answer 2

2

Question 3

What does the lower compartment of the TMJ consist of

Answer 3

Mandibular condyle and the inferior surface of the articular disc.
Hinge Joint

Question 4

What does the upper compartment of the TMJ consist of

Answer 4

Temporal bone and superior surface of the articular disc

Amphiarthrodial (Plane Joint)

Question 5

Describe the fibrous capsule of the TMJ

Answer 5

Upper capsule is loose (allows translation)
Lower capsule is tight (allows rotation)
Medial and Lateral portion is thicker

Question 6

What’s the purpose of the lateral ligament in the TMJ

Answer 6

Suspend mandible from temporal bone
Support lateral joint
Prevents excessive rotation and posterior displacement

Question 7

What’s the primary innervation for the TMJ

Answer 7

Facial and Trigeminal Nerves