Infratemporal Fossa Flashcards
infratemporal fossa
an irregularly shaped space, inferior to the temporal bone and below the zygomatic arch; medial to the mandible
contents of the infratemporal fossa
muscles of mastication (lateral and medial pterygoid muscles)
mandibular nerve V3 and its branches
otic ganglion
maxillary artery
pterygoid plexus of veins
muscles of mastication
temporalis
masseter
lateral pterygoid
medial pterygoid
temporalis attachments
superior attachment: parietal bone
inferior attachment: coronoid process of the mandible
temporalis main function
elevates mandible (closes the mouth)
anterior fibers: elevate mandible
posterior fibers: retract mandible
masseter attachments
superior: zygomatic arch
inferior: angle and ramus of the mandible
masseter function
elevation of mandible (closing the mouth)
medial pterygoid muscle attachments
superior: medial surface of the lateral pterygoid plate (of sphenoid bone)
inferior: angle of mandible (medial surface)
medial pterygoid muscle function
elevation of mandible
protrusion of mandible
lateral chewing movements
what fibers run in the same direction as masseter
medial pterygoid muscle fibers
what muscle lies on the medial surface of mandible
medial pterygoid muscle
what muscles lies on the lateral surface of mandible
masseter muscle
sphenoid bone
greater wing with lateral and medial pterygoid plates
lateral pterygoid muscle has how many heads
2
lateral pterygoid muscle attachments
from the lateral surface of the lateral pterygoid plate to condylar neck, TMJ capsule and articular disc
lateral pterygoid msucle function
protrusion of mandible
depression of mandible
lateral chewing movements (side-to-side movement)
mandibular movements
elevation, depression, protrusion, retraction and lateral excursion
what is the main force that depresses mandible
gravity
temporomandibular joint
synovial joint formed by the condyle of mandible and the mandibular fossa of the temporal bone
temporomandibular joint divided into compartments by the
articular disc
compartments of the temporomandibular joint
superior compartment permits anterior and posterior movement
inferior compartment is a hinge joint, permits depression and elevation
mandibular nerve
branch of CN V
mostly a sensory nerve, also has some motor fibers
passes through the foramen ovale to enter the infratemporal fossa
mandibular nerve sensory branches
lingual nerve
inferior alveolar nerve
buccal nerve
auriculotemporal nerve
motor branches of mandibular nerve
to muscles of mastication
buccal nerve
carries general sensory information from:
skin on the cheek
buccal mucous membrane
buccal gingiva of the mandibular posterior teeth 2nd and 3rd molar
lingual nerve
carries general sensory fibers from the anterior 2/3s of the tongue, floor of the mouth and mandibular gingiva
what nerve exits middle ear and joins lingual nerve
chorda tympani nerve, a branch of the facial nerve
chorda tympani carries
special sensory (taste) fibers from the anterior 2/3s of tongue and parasympathetic fibers, which synapse in the submandibular ganglion and then supply 2 salivary glands: submandibular and sublingual gland
after chorda tympani joins lingual nerve, the lingual nerve carries
all 3 types of fibers
general sensory, special sensory of taste parasympathetic fibers
inferior alveolar nerve carries
general sensory fibers from mandibular teeth and mandibular gingiva
branches of inferior alveolar nerve (IAN)
nerve to mylohyoid muscle: branches off just before IAN enters mandibular foramen, motor nerve to mylohyoid muscle and anterior belly of digastric muscle
mental nerve: terminal branch of IAN, it exits through the mental foramen and carries general sensory information from the skin and mucosa of the lower lip and chin
auriculotemporal nerve carries
general sensory fibers from: external ear and scalp of the temporal region, external auditory meatus and tympanic membrane, TMJ
also carries postganglionic parasympathetic nerve fibers to the parotid gland
auriculotemporal nerve makes a loop around
middle meningeal artery
the parasympathetic innervation of the parotid gland is from
glossopharyngeal nerve
otic ganglion fibers
the preganglionic fibers from CN IX reach otic ganglion located next to the V3 nerve in the infratemporal fossa
they synapse in the otic ganglion, and postganglionic fibers join the auriculotemporal nerve, a branch of V3, which carries them to the parotid gland
maxillary artery
main artery in the infratemporal fossa; branch of the external carotid artery
supplies blood to the deep part of face
branches of the maxillary artery
middle meningeal artery
inferior alveolar artery
pterygoid plexus of veins
located in the infratemporal fossa, around pterygoid muscles and maxillary artery
plexus protects maxillary artery from being compressed during mastication
plexus connects with facial and retromandibular veins
