temporal and infratemporal fossa Flashcards
temporal and infratemporal fossa
contiguous spaces on the lateral aspect of the head
temporal fossa
shallow depression superior to the zygomatic arch
contains temporalis muscle and its lood and nerve supply and the zygomaticotemporal branch of the maxillary nerve (V2)
over parts of parietal, frontal, temporal, sphenoid bones
contains pterion
features of mandible
has horizontally oriented body with alveolar sockets for teeth
vertically oriented ramus
angle in between
condyle on superior aspect of ramus - articulates with mandibular fossa
coronoid process anterior to condyle - insertion of temporalis muscle
separated by mandibular notch
angle
between body and ramus of mandible
condyle of mandible
on superior aspect of ramus and posterior
articulates to temporal bone via articular disc at mandibular fossa
coronoid process of mandible
anterior to condyle
site of insertion for temporalis muscle
mandibular foramen
inferior alveolar artery and nerve pass into mandible
on medial surface of mandible
artery and nerve to mylohyoid
branch off of inferior alveolar artery and nerve just before those enter the mandibular foramen
inferior alveolar artery and nerve
pass through mandibular foramen
innervate mandibular teeth
exit bone through mental foramen as mental artery and nerve
mental artery and nerve
continuation of inferior alveolar artery and nerve
exit mandible through mental foramen
lingula
medial to mandibular foramen
site of attachment of the sphenomandibular ligament
masseter muscle
inserts on lateral surface of ramus of mandible and angle
medial pterygoid muscle
inserts on medial surface of mandible inferior to the mandibular forame
zygomatic arch
formed by articulation of the temporal process of zygoma with the zygomatic process of the temporal bone
muscles of mastication (list)
temporalis
masseter
medial
lateral pterygoids
all innervated by motor branch of mandibular nerve (CN V3)
movements of mandible (list)
elevation or closing the jaw: temporalis, masseter and medial pterygoid
depression or opening of jaw: gravity mylohyoid, digastric, geniohyoid
protrusion or anterior movement of the jaw: lateral pterygoid assisted by medial pterygoid
retraction or posterior movement of the jaw: posterior, horizontal fibers of temporalis (assisted by digastric and geniohyoid)
pterygoids
move mandible in sliding and rotatory (grinding) manner from side-to-side - important in chewing
also help to elevate protrude jaw
innervated by CN V3 (motor branch of mandibular)
elevation or closing the jaw
produced by temporalis, masseter, and medial pterygoid muscles
depression or opening of the jaw
gravity, mylohyoid, digastric, geniohyoid
protrusion or anterior movement of the jaw
lateral pterygoid (assisted somewhat by medial pterygoid)
retraction or posterior movement of the jaw
posterior, horizontal fibers of temporalis (assisted by digastric and geniohyoid)
temporalis muscle
originates from floor of temporal fossa
passes medial to zygomatic arch
inserts on coronoid process of mandible
external surface covered by temporalis fascia (also originates from this)
temporalis fascia
covers external surface of temporalis muscle
arises from superior temporal line and inserts on and supports zygomatic arch
resists inferior pulll of masseter muscle
masseter muscle
originates on zygomatic arch
inserts on lateral aspect of ramus and angle of mandible
parotid duct
pierces buccinator to drain into the oral cavity opposite the second maxillary molar tooth
buccinator muscle
parotid duct pierces
innervated by CN VII
sphenoid bone
keystone of skull
articulates with 12 other bones
superior orbital fissure lies between lesser and greater wings
bilaterally symmetrical
anterior surface of greater wing is in orbit
posterior surface is in middle cranial fossa
sella turcia
in sphenoid bone
pituitary gland contained in it
nerve of the pterygoid canal
travels through fibrocartilage in foramen lacerum in anteromedial direction
temporomandibular joint (TMJ)
contains fibrous articular disk
where condyle of mandible articulates with the mandibular fossa of the temporal bone
if condyle moves anterior, mandible will dislocate
synovial joint
when mouth opens, mandible rotates like a hinge and slides anteriorly onto the articular tubercle - produces wider opening between upper and lower teeth
lateral pterygoid plate of sphenoid
where medial and lateral pterygoids originate from
medial pterygoid
inserts on medial side of ramus and angle of the mandible inferior to the mandibular foramen
lateral pterygoid
inserts onto the capsule and articular disc of the TMJ and the neck of the mandible (pterygoid fovea)
if one lateral pterygoid is paralyzed, the contraction of the contralateral muscle will cause the jaw to protrude toward the side of the paralyzed muscle
sphenomandibular ligament
runs from the spine of the sphenoid to the lingula on the mandibular ramus
helps maintain the mandibular condyle in position and becomes fully taut when the jaw is half open
stylomandibular ligament
insignificant thickening of the deep cervical fascia
infratemporal fossa
extracranial area located inferior to the temporal fossa and zygomatic arch deep to ramus of mandible posterior to tuberosity of maxilla lateral to petrygoid plate anterior to styloid process superior border = infratemporal crest of greater wing of sphenoid open inferiorly contains: two pterygoid muscles maxillary artery mandibular nerve (V#) chorda tympani nerve pterygoid venous plexus parasympathetic otic ganglion
external carotid path
ascends posterior to the ramus of the mandible
distal portion runs through deep lobe of parotid gland and bifurcates into maxillary and superficial temporal arteries
maxillary artery
one of two terminal branches of external carotid artery
originates within deep lobe of parotid gland
travels in anteromedial and slightly superior direction across the infratemporal fossa from lateral to medial
passes through pterygomaxillary fissure into pterygopalatine fossa
braches of maxillary artery
deep auricular anterior tympanic middle meningeal accessory meningeal inferior alveolar
middle meningeal artery
passes between the two roots of the auriculotemporal nerve
ascends to and through foramen spinosum
enters cranial cavity
main supplier of dura mater
inferior alveolar artery
travels inferiorly to enter mandibular foramen
branch of maxillary artery
supplies mandibular teeth and soft tissues
exist mandible through mental formen and becomes mental artery
lesser branches of maxillary (first part)
deep auricular
anterior tympanic
accessory meningeal
blood to external acousitic meatus, middle ear, and dura mater
branches of second portion of maxillary artery
branches to muscles of temporal and infratemporal fossae
named for muscles supplied
branches of mandibular nerve
enters infratemporal foassa through foramen ovale and innervates deeper structures of the face and oral cavity
only branch of trigeminal nerve with somatic efferent motor components
4 to muscles of mastication and 4 other muscles
plus 5 sensory branches:
inferior alveolar
lingual
auriculotemporal
meningeal
buccal
inferior alveolar nerve
branch of mandibular nerve
enters mandibular foramen after giving off motor nerve to mylohyoid and anterior belly of digastric
sensory to mandibular teeth
as terminal mental nerve, sensory to lower lip and chin
mental nerve
terminal branch of inferior alveolar nerve, branch of mandibular nerve
sensory innervation to chin and lower lip
lingual nerve
branch of mandibular nerve
general sensation to anterior 2/3 of tongue and floor of mouth
auriculotemporal nerve
branch of mandibular nerve
travels besider parotid gland
ascends next to superficial temporal artery to temporal region
sensory to temporal skin, ear structures, TMJ and parotid gland
also carries secretomotor parasympathetic postganglionic fibers from the otic ganglion to the parotid
meningeal nerve
travels with the middle meningeal artery through foramen spinosum
sensory innervation to dura mater of middle cranial fossa
branch of mandibular nerve
buccal nerve
branch of mandibular nerve
sensory to skin, oral mucosa, and gingiva in cheek region
motor branches of mandibular nerve
to 4 muscles of mastication plus: anterior belly of digastric mylohyoid tensor veli palatini tensor tympani
chorda tympani
formed by preganglionic parasympathetic fibers from teh brainstem that travel with the facial nerve before branching from the facial nerve in the facial canal
runs anteriorly through middle ear between malleus and incus
enters infratemporal fossa by passing thorugh petrotympanic fissure
goes with lingual nerve and synapses on submandibular ganglion
submandibular ganglion
where chorda tympani synapses
hangs off lingual nerve
postganglionic secretomotor fibers from it travel to submandibular and sublingual salivary glands and minor microscopic salivary glands in inferior oral cavity
geniculate gangion
of CN VII
where taste fibers from anterior 2/3 of tongue have pseudo-unipolar nerve cell bodies
afferent special sense taste fibers travel here from tongue to lingual nerve to chorda tympani to CN VII to brainstem
tympanic nerve
preganglionic parasympathetic fibers leave glossopharyngeal nerve (CN IV) inferior to jugular foramen
enter middle ear and ascen on promontory in tympanic plexus
exit as lesser petrosal
eventually supply parasympathetic nerve supply to parotid gland
lesser petrosal nerve
pregangionic prarsympathetic fibers from CN IX and tympanic nerve
when tympanic nerve leaves tympanic plexus
reneter cranial cavity
travels down petrous ridge
exists through foramen ovale
synapses on otic ganglion
part of parasympathetic nerve supply to parotid gland
otic ganglion
wehre preganglionic parasympathetic fibers from CN IX/tympanic nerve/lesser petrosal nerve synapse
send postganglionic parasympathetic secretomotor fibers along auriculotemporal nerve to parotid gland
on the medial side of mandibular nerve just inferior to foramen ovale and near origin of auriculotemporal nerve
pterygoid venous plexus
receives some blood from opthalmic and facial veins
drains the infratemporal fossa into maxillary vein
maxillary vein joins superficial temporal vein to make retromandibular vein
also has direct valveless drainage into cavernous sinus so infections can spread there and lead to sinus thrombosis
