Muscles of Mastication - year1 revision

Question 1

What are the 4 muscles of mastication? (skull to mandible muscles)

Answer 1

Masseter
Temporalis
Medial Pterygoid
Lateral Pterygoid

Question 2

What is the origin and insertion of the superficial masseter?

Answer 2

Zygomatic arch - Angle/ramus of the mandible

Question 3

What innervates the masseter muscle?

Answer 3

CNV3 motor root - masseteric nerve

Question 4

What is the origin and insertion of the deep masseter?

Answer 4

Inner aspect of the zygomatic arch - angle/ramus of the mandible

Question 5

What is the origin and insertion of the temporalis?

Answer 5

origin = inferior temporal line and fascia
insertion = coronoid process

Question 6

What is the action of the temporalis?

Answer 6

Jaw elevation and retrusion (posterior fibres)

Question 7

What innervates the temporalis muscle?

Answer 7

CNV3 motor root - temporal nerve

Question 7

what is the action of the lateral pterygoid? (inferior and superior head)

Answer 7

complex function
inferior head
- pulls condyle forward
- bilateral = protrusion and assists opening
- unilateral = lateral excursion
superior head
- active during retrusion and closing

Question 7

what is the action of the medial pterygoid?

Answer 7

jaw elevation
unilateral - assists protrusion and lateral excursion