Infratemporal Fossa Flashcards
parotid region
1) traversing the facial nerve
- CN VII enters ITF via the stylomastoid foramen
2) common carotid
- reaches TMJ and external terminated to sup. temporal and maxillary artery
3) pterygoid venous plexus
- retromandibular vein traverses the gland and also joins external jugular
innervation of temporal fossa
1) auriculotemporal nerve
- from V3
- temporal fossa
2) splits around middle meningeal artery
innervation of parotid gland
1) GSA: auriculotemporal nerve V3 and great auricular C2-C3
2) GVE:
- sympathetic traveling via arteries
- parasympathetic from CN IX to otic ganglion/V3 then auriculotemporal nerve
parotid gland supplies
25% of salivary volume
masticator space
1) includes the temporal and infratemporal fossae
infratemporal fossa contents
1) muscles of mastication
2) V3 of trigeminal nerve
3) chorda tympani branch of facial nerve
4) maxillary artery and vein
masticator space fascia
1) derived from investing later of deep cervical fascia
- encapsulates the parotid
2) envelopes the mandible and muscles of mastication
3) includes branches of CN V and the maxillary artery and vein
superficial muscles of mastication
1) temporalis
- temporal fossa to coronoid process
- extends to ramus of the mandible on medial side
- closing and retrusion
2) masseter
- zygomatic arch to the ramus of the mandible
- closing
deep muscles of mastication
1) medial pterygoid
- deep lateral pterygoid plate of sphenoid to medial surface of mandibular ramus (lower half)
- strong elevator and protrusion
- lateral movement as well
2) lateral pterygoid
- superficial lateral pterygoid plate of sphenoid to maxilla
- protrusion and depression
—
a nerve bundle emerges between
pterygomandibular raphae
1) site for anesthesia
injecting into parotid gland
1) facial paralysis since CN VII is in there
2) temporary
buccinator
1) pushes food back to center while chewing
V3 division of CN V
1) origin to the maxillary and mandibular arches and the muscles of mastication
innervation of superficial face
1) sensory CN V
- from 1st branchial arch
2) motor CN VII
- from 2nd branchial arch
- facial nerve
trigeminal ganglion
1) lies within the middle cranial fossa
2) equivalent to dorsal root ganglion
- nerve cell bodies (no synapse)
- pseudounipolar
nuclei of trigeminal pathway
1) motor
2) mesencephalic
3) pontine / principal
4) spinal trigeminal
motor nuclei
1) masticatory muscles
2) motor component
mesencephalic
2) proprioception from muscles of mastication
principal / pontine
1) touch from face
2) sensory
spinal trigeminal
1) touch, pain, temperature from face
2) sensory
jaw jerk reflex arc
1) proprioceptive fibers from masticatory muscles, TMJ, and PDL travel in the motor root
2) proprioceptive nerve cells bodies in the mesencephalic nucleus
3) some of these synapse in the nerve cell bodies of the trigeminothalamic tract, sensory to the brain
4) however, some of these synapse onto motor nerve cell bodies in the motor nucleus
5) monosynaptic reflex arc
V3 short stem, then splits into 2 division
1) stem
- medial pterygoid nerve
- tensor tympani nerve
- tensor palatini nerve
- meningeal branch
V3 anterior division
1) motor division
- deep temporal nerves (2)
- masseteric nerve
- lateral pterygoid nerve
2) one sensory branch
- long buccal nerve
V3 posterior division
1) sensory
- auriculotemporal
- lingual nerve
- inferior alveolar (mylohyoid, mental, incisive)
2) all sensory except mylohyoid nerve
additional innervation in the infratemporal fossa
1) chorda tympani
- branch of CN VII
- caries taste fibers from anterior tongue
- secretomotor fibers to salivary glands
2) joins lingual nerve of V3 in ITF
blood supply to infratemporal fossa
1) maxillary artery
- mandibular
- pterygoid
- pterygopalatine
mandibular portion of maxillary artery
1) deep auricular
2) anterior tympanic
3) middle meningeal
4) accessory meningeal
5) inferior alveolar*
- mylohyoid, mental, and incisive branches
- primary blood supply to mandible
pterygoid branch
1) deep temporal
2) medial pterygoid
3) lateral pterygoid
4) masseteric
5) buccal
pterygopalatine
1) posterior superior alveolar
2) infraorbital
3) artery of pterygoid canal
4) pharyngeal branch
5) descending palatine
6) sphenopalatine
pterygoid venous plexus
1) primary drainage to maxillary vein
2) connections to
- cavernous sinus
- facial vein
- inferior ophthalmic
- pharyngeal plexus
