muscles of mastication Flashcards
temporalis m origin
- bony surfaces of temporal fossa
- inferior temporal line
- overlying temporal fascia
bilateral action of temporalis m
- resting tonus
- elevate (anterior fibers)
- retract (posterior fibers)
innerv of temporalis m
deep temporal n (branch of mandibular nerve)
blood supply of temporalis m
- deep temporal a
- middle temporal a
most powerful muscle in the body
massetor m
what 3 things are superficial to the massetor m
- parotid gland and duct
- transverse facial a
- branches of CN 7
origin of superficial head of the massetor m
- maxillary process of zygomatic bone
- inferior aspect of anterior 2/3 of zygomatic arch
origin of deep head of the masseter m
- medial aspect of zygomatic arch
- inferior margin of post 1/3 of zygomatic arch
bilateral action of masseter m (superficial)
- elevate
- protrusion
unilateral action of masseter m
lateral movement (ipsilateral)
n and a supply of masseter m
masseteric n, masseteric a and transverse facial a
superficial head of medial pterygoid m
origin: tuberosity of maxilla + pyramidal process of palatine bone
insertion: pterygoid rugosity of medial aspect of ramus
deep head of medial pterygoid m
origin: medial surface of lateral pterygoid plate
insertion: pterygoid rugosity on medial aspect of ramus
action of medial pterygoid m (superficial and deep heads)
bilateral: elevate and protrusion
unilateral: lateral movement to the OPPOSITE side**
if the right medial pterygoid m is damaged, what is the resulting action
moves to the right
the masseter and medial pterygoid form a
muscular sling
innervation of medial pterygoid m
nerve to the medial pterygoid
the only horizontal m of mastication
lateral pterygoid m
superior head of lateral pterygoid m ORIGIN
roof of IT fossa (inferior aspect of GW of sphenoid and IT crest)
inferior head of lateral pterygoid m ORIGIN
lateral aspect of lateral pterygoid plate
bilateral action of lateral pterygoid (upper)
- elevate
- protrusion
- DEPRESSION
unilateral action of lateral pterygoid m
CONTRALATERAL excursion**
bilateral action of lateral pterygoid (lower)
- protrusion
- DEPRESSION
- NO elevation
which muscles elevate
- temporalis
- masseter
- medial pterygoid
- lateral pterygoid (superior head)
which muscles depress the mandible
- lateral pterygoid
- suprahyoid m (except for stylohyoid m)
- platysma
which muscles protrude
- lateral pterygoid
- medial pterygoid
- masseter (superficial)
which muscles retrude
- temporalis (posterior)
- masseter (deep)
which muscles move to the right
- R temporalis
- R masseter
- L medial and lateral pterygoid
which muscles move to the left
- L temporalis
- L masseter
- R medial and lateral pterygoid
temporalis m insertion
- medial aspect of coronoid process
- anterior margin of mandibular ramus
unilateral action of temporalis m
lateral movement (ipsilateral)
insertion of masseter m (superior)
- angle of mandible
- lateral surface of mandibular ramus
insertion of masseter m (deep)
central and upper part of mandibular ramus
bilateral action of masseter muscle (superficial)
- elevate
- protrusion
bilateral action of masseter muscle (deep)
- elevate
- RETRACT
lateral pterygoid (superior head) INSERTION
- capsule of TMJ
- articular disc
- pterygoid fovea (minor)
lateral pterygoid m (lower) INSERTION
- pterygoid fovea
- capsule of TMJ (minor)
roof of IT fossa
GW of sphenoid and inferior portion of temporal bone
anterior border of IT fossa
tuberosity of maxilla
posterior border of IT fossa
styloid process and condylar process
medial border of IT fossa
lateral pterygoid plate of sphenoid bone
lateral border of IT fossa
medial surface of the mandibular ramus and coronoid process
