[ANAT] MUSCLES OF MASTICATION

Question 1

4 Muscles of mastication

Answer 1

temporalis
masseter
lateral pterygoid
medial pterygoid

Question 2

which nerve generally supplies all 4 muscles?

Answer 2

mandibular

Question 3

which embryological structure are all 4 muscles developed from?

Answer 3

mesoderm of 1st pharyngeal arch

Question 4

all 4 muscles act on

Answer 4

TMJ

Question 5

temporalis lies in

Answer 5

temporal fossa

Question 6

masseter overlies

Answer 6

ramus of mandible

Question 7

medial & lateral pterygoids are content of

Answer 7

infratemporal fossa

Question 8

origin of temporalis

Answer 8

floor of temporal fossa & deep surface of temporal fascia

Question 9

insertion of temporalis

Answer 9

all of coronoid process except lateral surface
extends on anterior surface of ramus down till last molar

Question 10

origin of superficial head of masseter

Answer 10

anterior 2/3 of zygomatic arch

Question 11

origin of deep head of masseter

Answer 11

posterior 1/3 of zygomatic arch

Question 12

insertion of masseter

Answer 12

ramus (lateral surface)

Question 13

origin of upper head lateral pterygoid

Answer 13

infratemporal crest & greater wing of sphenoid

Question 14

origin of lower head of lateral pterygoid

Answer 14

lateral aspect of lateral pterygoid plate

Question 15

insertion of lateral pterygoid

Answer 15

fovea
capsule of TMJ
articular disk of TMJ

Question 16

origin of superficial head medial pterygoid

Answer 16

turberosity of maxilla

Question 17

origin of deep head of medial pterygoid

Answer 17

medial aspect of lateral pterygoid plate

Question 18

insertion of medial pterygoid

Answer 18

angle of mandible (medial aspect)

Question 19

nerve supply of temporalis

Answer 19

2 deep temporal nerves
~from anterior division of mandibular nerve

Question 20

nerve supply of masseter

Answer 20

masseteric branch
~from anterior division of mandibular nerve

Question 21

nerve supply of lateral pterygoid

Answer 21

pterygoid branch
~from anterior division of mandibular nerve

Question 22

nerve supply of medial pterygoid

Answer 22

branch from trunk of mandibular nerve

Question 23

action of anterior vertical fibers of temporalis

Answer 23

elevation of mandible

Question 24

action of posterior horizontal fibers of temporalis

Answer 24

retraction of mandible

Question 25

action of deep vertical fibers of masseter

Answer 25

elevation of mandible

Question 26

action of superficial oblique fibers of masseter

Answer 26

protraction of mandible

Question 27

action of lateral pterygoid

Answer 27

depresses mandible-->opens mouth protrudes mandible side to side movement (for chewing)

Question 28

action of medial pterygoid

Answer 28

elevates mandible protrudes mandible side to side for chewing

Question 29

contraction of medial & lateral pterygoid causes

Answer 29

pushing of mandible to opposite side

Question 30

all muscles are supplied by anterior division of mandible EXCEPT

Answer 30

medial pterygoid

Question 31

all muscles cause protrusion of mandible EXCEPT

Answer 31

temporalis

Question 32

All muscles cause elevation of mandible EXCEPT

Answer 32

lateral pterygoid

Question 33

all muscles are inserted on inner side of ramus EXCEPT

Answer 33

masseter

Question 34

only retractor of mandible

Answer 34

temporalis

Question 35

only depressor of mandible

Answer 35

lateral pterygoid

Question 36

upper border relations of pterygoid

Answer 36

deep temporal nerve masseteric nerve

Question 37

lower border relations of pterygoid

Answer 37

lingual nerve inferior alveolar nerve+ vessels

Question 38

relations of pterygoid between 2 heads of

Answer 38

buccal nerve maxillary artery

Question 39

superficial (lateral) relations of pterygoid (5)

Answer 39

1-ramus mandible 2-superficial head of medial pterygoid 3-tendon of temporalis 4-maxillary artery 5-pterygoid venous plexus

Question 40

deep (medial) relations of pterygoid (8)

Answer 40

1-deep head of medial pterygoid 2-tensor palati 3-mandibular trunk 4-otic ganglia 5-chorda tympani 6-middle meningeal artery 7-maxillary artery 8-spheno-mandibular ligament