TMJ and muscles of mastication

Question 1

what type of joint is the TMJ?

Answer 1

modified hinge synovial joint

Question 2

what type of cartilage covers the articular surfaces of the TMJ?

Answer 2

fibrocartilage

Question 3

what ligaments are involved in the TMJ?

Answer 3

2 extrinsic =
- sphenomandibular
- stylomandibular

1 intrinsic =
- lateral ligament

Question 4

what are the 5 movements that the TMJ permits?

Answer 4

• protrusion
• retraction
• elevation
• depression
• lateral movements

Question 5

what pharyngeal arch do the muscles of mastication derive from?

Answer 5

first pharyngeal arch

Question 6

what are the muscles of mastication innervated by?

Answer 6

CNV

Question 7

where does the temporalis muscle originate from?

Answer 7

temporal fossa & fascia

Question 8

where does the temporalis muscle insert into?

Answer 8

coronoid process of mandible & anterior border of ramus

Question 9

what is the function of the temporalis muscle?

Answer 9

retracts & elevates the mandible

Question 10

what is the temporalis muscle innervated by?

Answer 10

deep temporal nerves from CNV3

Question 11

where does the masseter muscle originate from?

Answer 11

maxillary process of zygomatic bone & anterior 2/3rd of inferior border of zygomatic arch

Question 12

where does the masseter muscle insert into?

Answer 12

angle & lateral surface of ramus of mandible

Question 13

what is the function of the masseter muscle?

Answer 13

elevates the mandible

Question 14

what is the masseter innervated by?

Answer 14

masseteric nerve from CNV3

Question 15

where does the medial pterygoid originate from?

Answer 15

medial surface of lateral pterygoid & maxillary tuberosity & pyramidal process of palatine bone

Question 16

where does the medial pterygoid insert into?

Answer 16

medial surface of the ramus & angle of mandible

Question 17

what is the function of the medial pterygoid?

Answer 17

• elevates mandible
• assists with lateral movements

Question 18

what nerve innervates the medial pterygoid?

Answer 18

nerve to medial pterygoid from CNV3

Question 19

where does the lateral pterygoid originate from?

Answer 19

infratemporal surface of greater wing of sphenoid bone & lateral surface of lateral pterygoid plate

Question 20

where does the lateral pterygoid muscle insert?

Answer 20

front of the neck of the mandible

Question 21

what is the function of the lateral pterygoid?

Answer 21

protrudes the mandible
- assists with lateral and depression movements too