muscles of mastication

Question 1

temporalis m origin

Answer 1

• bony surfaces of temporal fossa
• inferior temporal line
• overlying temporal fascia

Question 2

bilateral action of temporalis m

Answer 2

• resting tonus
• elevate (anterior fibers)
• retract (posterior fibers)

Question 3

innerv of temporalis m

Answer 3

deep temporal n (branch of mandibular nerve)

Question 4

blood supply of temporalis m

Answer 4

• deep temporal a

- middle temporal a

Question 5

most powerful muscle in the body

Answer 5

massetor m

Question 6

what 3 things are superficial to the massetor m

Answer 6

• parotid gland and duct
• transverse facial a
• branches of CN 7

Question 7

origin of superficial head of the massetor m

Answer 7

• maxillary process of zygomatic bone

- inferior aspect of anterior 2/3 of zygomatic arch

Question 8

origin of deep head of the masseter m

Answer 8

• medial aspect of zygomatic arch

- inferior margin of post 1/3 of zygomatic arch

Question 9

bilateral action of masseter m (superficial)

Answer 9

• elevate

- protrusion

Question 10

unilateral action of masseter m

Answer 10

lateral movement (ipsilateral)

Question 11

n and a supply of masseter m

Answer 11

masseteric n, masseteric a and transverse facial a

Question 12

superficial head of medial pterygoid m

Answer 12

origin: tuberosity of maxilla + pyramidal process of palatine bone
insertion: pterygoid rugosity of medial aspect of ramus

Question 13

deep head of medial pterygoid m

Answer 13

origin: medial surface of lateral pterygoid plate
insertion: pterygoid rugosity on medial aspect of ramus

Question 14

action of medial pterygoid m (superficial and deep heads)

Answer 14

bilateral: elevate and protrusion
unilateral: lateral movement to the OPPOSITE side**

Question 15

if the right medial pterygoid m is damaged, what is the resulting action

Answer 15

moves to the right

Question 16

the masseter and medial pterygoid form a

Answer 16

muscular sling

Question 17

innervation of medial pterygoid m

Answer 17

nerve to the medial pterygoid

Question 18

the only horizontal m of mastication

Answer 18

lateral pterygoid m

Question 19

superior head of lateral pterygoid m ORIGIN

Answer 19

roof of IT fossa (inferior aspect of GW of sphenoid and IT crest)

Question 20

inferior head of lateral pterygoid m ORIGIN

Answer 20

lateral aspect of lateral pterygoid plate

Question 21

bilateral action of lateral pterygoid (upper)

Answer 21

• elevate
• protrusion
• DEPRESSION

Question 22

unilateral action of lateral pterygoid m

Answer 22

CONTRALATERAL excursion**

Question 23

bilateral action of lateral pterygoid (lower)

Answer 23

• protrusion
• DEPRESSION
• NO elevation

Question 24

which muscles elevate

Answer 24

• temporalis
• masseter
• medial pterygoid
• lateral pterygoid (superior head)

Question 25

which muscles depress the mandible

Answer 25

- lateral pterygoid - suprahyoid m (except for stylohyoid m) - platysma

Question 26

which muscles protrude

Answer 26

- lateral pterygoid - medial pterygoid - masseter (superficial)

Question 27

which muscles retrude

Answer 27

- temporalis (posterior) | - masseter (deep)

Question 28

which muscles move to the right

Answer 28

- R temporalis - R masseter - L medial and lateral pterygoid

Question 29

which muscles move to the left

Answer 29

- L temporalis - L masseter - R medial and lateral pterygoid

Question 30

temporalis m insertion

Answer 30

- medial aspect of coronoid process | - anterior margin of mandibular ramus

Question 31

unilateral action of temporalis m

Answer 31

lateral movement (ipsilateral)

Question 32

insertion of masseter m (superior)

Answer 32

- angle of mandible | - lateral surface of mandibular ramus

Question 33

insertion of masseter m (deep)

Answer 33

central and upper part of mandibular ramus

Question 34

bilateral action of masseter muscle (superficial)

Answer 34

- elevate | - protrusion

Question 35

bilateral action of masseter muscle (deep)

Answer 35

- elevate | - RETRACT

Question 36

lateral pterygoid (superior head) INSERTION

Answer 36

- capsule of TMJ - articular disc - pterygoid fovea (minor)

Question 37

lateral pterygoid m (lower) INSERTION

Answer 37

- pterygoid fovea | - capsule of TMJ (minor)

Question 38

roof of IT fossa

Answer 38

GW of sphenoid and inferior portion of temporal bone

Question 39

anterior border of IT fossa

Answer 39

tuberosity of maxilla

Question 40

posterior border of IT fossa

Answer 40

styloid process and condylar process

Question 41

medial border of IT fossa

Answer 41

lateral pterygoid plate of sphenoid bone

Question 42

lateral border of IT fossa

Answer 42

medial surface of the mandibular ramus and coronoid process