Lecture 1- Muscles of mastication

Question 1

how many muscles of mastication

Answer 1

4

Question 2

all muscles act to

Answer 2

move the mandible at the temporomandibular joint (TMJ)

Question 3

movement of the TMJ needed

Answer 3

when chewing

Question 4

all muscles of mastication supplied by

Answer 4

mandibular division of the tirgeminal nerve

Question 5

trigeminal nerve

Answer 5

branch CN V

Question 6

what are the muscles of mastication

Answer 6

• temporalis
• masseter
• pterygoid- medial and lateral

Question 7

which muscles of mastication are palpable

Answer 7

When clenching your jaw you can easily palpate the contraction of the temporalis and masseter muscles by feeling over the area of your temples (temporalis), and at the corner of your jaw as you clench your teeth (masseter).
The pterygoid muscles, however, are not palpable and lie deep to the mandible. They take their origin from two bony plate-like projections at the base of the skull, called the pterygoid plates (hence the name of the muscles). Each pterygoid muscle is angled slightly different, and inserts on to separate areas of the mandible thus conferring their different actions on the jaw (opening vs closing).

Question 8

all muscles of mastication, except one

Answer 8

elevate the mandible (close the jaw)

Question 9

muscles involved in depressing the mandible are called

Answer 9

supra hyoids- lie above the hyoids

- assisted by the pull of gravity and lateral pterygois