Temporal Region: Muscles of Mastication

Question 1

what are the 4 true muscles of mastication

Answer 1

temporalis, masseter, medial and lateral pterygoid

Question 2

what are the 4 accessory muscles of mastication

Answer 2

digastric muscle, buccinator, tongue muscles and orbicularis oris

Question 3

what are the 3 jaw closers

Answer 3

temporalis, masseter, and medial pterygoid

Question 4

what is the jaw protractor

Answer 4

the lateral pterygoid

Question 5

what is the jaw opener muscle

Answer 5

digastric muscle

Question 6

where does V3 mandibular nerve emerge into

Answer 6

the infratemporal fossa

Question 7

what are the 3 sensory parts of V3 mandibular nerve

Answer 7

inferior alveolar nerve: lower jaw and teeth, buccal nerve: interior mouth, and lingual nerve: anterior 2/3 tongue

Question 8

what are the 2 motor parts of V3 mandibular nerve

Answer 8

muscles of mastication and tensor veli palatine muscle and nerve to mylohyoid: anterior belly of digastrics and mylohyoid muscle

Question 9

what parasympathetics from CN7 do V3 carry

Answer 9

preganglionic parasympathetics from chorda tympani to submandibular ganglion and lingual nerves to submandibular and sublingual glands

Question 10

what are the 4 movements of the temporomandibular joint

Answer 10

depression, elevation, protrusion, and retraction

Question 11

what innervates the anterior belly of the digastric muscle

Answer 11

mandibular V3 nerve

Question 12

what innervates the posterior belly of the digastric muscle

Answer 12

facial nerve 7

Question 13

what are the 3 cranial nerves involved in general sensation of mastication

Answer 13

maxillary nerve (V2), mandibular nerve (V3) and glossopharyngeal nerve (9)

Question 14

what motion does mastication involve

Answer 14

a roughly circular jaw motion

Question 15

what does the maxillary nerve V2 give sensation to

Answer 15

hard palate and upper teeth

Question 16

what does the mandibular nerve (V3) give sensation to

Answer 16

sensory from anterior 2/3 of tongue and lower teeth

Question 17

what does the glossopharyngeal nerve (CN9) give sensation to

Answer 17

sensory from posterior 1/3 of tongue

Question 18

how does the jaw open/depress

Answer 18

with gravity and neck muscles

Question 19

how does the jaw protrude

Answer 19

the mandibular condyle slides anteriorly by the lateral pterygoid (CN V3)

Question 20

what helps position the food

Answer 20

tongue (CN 12) and cheek muscles (buccinator CN7)

Question 21

how does the jaw contract/move towards the chewing side

Answer 21

by contraction of the chewing side masseter (CN V3) and contralateral medial pterygoid (CN V3)

Question 22

what happens with the power stroke

Answer 22

the jaw elevates (masseter, temporalis, and medial pterygoid) and the jaw moves toward the non-chewing side (contralateral masseter, chewing side medial pterygoid)

Question 23

what are the 3 ligaments that support the mandible and limit the TMJ ranges of motion

Answer 23

sphenomandibular, temporomandibular, and stylomandibular

Question 24

how many synovial cavities are in the TMJ

Answer 24

two: superior and inferior synovial cavities

Question 25

where is the condyle when the jaw is closed

Answer 25

below the fossa

Question 26

where is the condyle when the jaw is opened

Answer 26

under the tubercle

Question 27

what 2 actions are required for a full gap opening

Answer 27

both sliding and hinge actions

Question 28

what are 3 symptoms of TMJ dysfunction

Answer 28

pain in preauricular region and muscles of mastication, limit range of movements, and clicking sounds