Joints - TMJ

Question 1

What are joints?

Answer 1

An articulation where 2 bones meet

Question 2

Different types of joints? (3)

Answer 2

1. Cartilaginous - Intervertebral discs
2. Fibrous - Sutures on skull
3. Synovial - TMJ

Question 3

What are the features of a synovial joint?

Answer 3

1. Fibrous capsule -outer layer
2. Synovial membrane - covers no articulating areas
3. Articulating cartilage - covers articulating surfaces
4. Joint cavity - contains articulating fluid

Question 4

What does the TMJ articulate with?

Answer 4

Condyle of mandible articulates with Mandibular fossa and articular tubercle

Question 5

What type of joint is the TMJ ?

Answer 5

Synovial joint
- specifically a modified hinge joint

Question 6

What is the disc in the TMJ made of?

Answer 6

Fibrocartilage

Question 7

Why is fibrocartilage used in the TMJ?

Answer 7

Used because it thought but can also compress and absorb lots of pressure

Question 8

What are the ligaments of the TMJ?

Answer 8

1. Shenomandibular ligament- sphenoid bone - lingula in inner surface if mandible above Mandibular fossa
2. Stylomandibular ligament - styloid process to angle of mandible
3. Lateral Temporomandibular ligament - attaches to the capsule and thickens it

Question 9

How does the TMJ move?

Answer 9

1- Hinge - done by the inferior compartment and head of mandible rotates around the transverse axis

2- Gliding - head of mandible and disc slide forward out of Mandibular fossa on to articular tubercle (Translation)

Question 10

What are the move,ents of the TMJ?

Answer 10

1. Depression
2. Elevation
3. Protrusion
4. Retrusion
5. Lateral excursion/swing