HS2-7 Parotid Temporal Infratemporal Regions Flashcards
What is another name for the parotid region?
retromandibular fossa
Where is the parotid region located?
posterior to ramus of mandible but anteroinferior to ear
[essentially, where the parotid gland is located]
What is the largest salivary gland in the body?
parotid gland
What structure is found just deep to the parotid gland?
masseter muscle
What structure permits the passage of saliva from the parotid gland to the oral cavity?
parotid duct
Describe the pathway of the parotid duct.
crosses masseter
pierces buccinator
enters oral cavity @ parotid papilla (opposite second upper molar)
List five major structures that run through the parotid gland.
facial nerve
auriculotemporal nerve (branch of CN V3)
external carotid artery
superficial temporal artery
retromandibular vein
What are the terminal branches of the external carotid artery? (2)
superficial temporal artery
maxillary artery
The superficial temporal artery runs alongside what structure?
runs alongside the auriculotemporal nerve on the side of the head
What structures form the retromandibular vein? (2)
superficial temporal vein
maxillary vein
The retromandibular vein drains into
internal or external jugular veins
Describe the parasympathetic innervation of the parotid gland. (3)
parasympathetic fibers run with CN IX (tympanic branch, then lesser petrosal nerve)
synapse at otic ganglion in infratemporal fossa
postganglionic fibers travel w/ auriculotemporal nerve to parotid gland
What is gustatory sweating?
excessive sweating, flushing, or feelings of warmth in response to gustatory stimuli
What causes gustatory sweating?
aberrant innervation of sweat glands by regrowing parasympathetic fibers associated with the auriculotemporal nerve that were previously damaged
What are the boundaries of the temporal fossa?
superiorly = temporal lines
inferiorly = superior border of zygoma
The temporal fossa includes what 4 bones that form the skull?
frontal
parietal
temporal
sphenoid
What is the major structure associated with the temporal fossa?
temporalis muscle
What is the largest muscle of mastication?
temporalis
What is the origin of the temporalis muscle?
temporal fossa
What is the insertion of the temporalis muscle?
coronoid process of mandible
What innervates the temporalis muscle?
branches of mandibular nerve (CN V3)
What provides arterial supply to the temporalis muscle?
deep temporal arteries (from maxillary artery)
What are the boundaries of the infratemporal fossa?
ramus of mandible (lateral)
greater wing of sphenoid bone (superior)
lateral pterygoid plate of sphenoid bone (medial)
maxilla (anterior)
Gustatory sweating is often seen after what surgical procedure?
parotidectomy
List the interconnections of the infratemporal fossa. (5)
connected to orbit via inferior orbital fissure
connected to middle cranial fossa via foramina ovale + spinosum
connected to temporal fossa
connected to pterygopalatine fossa via pterygomaxillary fissure
directly connected to oral cavity
What are the contents of the infratemporal fossa? (7)
medial pterygoid muscle
lateral pterygoid muscle
branches of V3
otic ganglion
chorda tympani
branches of maxillary artery
pterygoid plexus of veins
The muscles of mastication are innervated by
branches of V3
The muscles of mastication produce movement at which joint?
temporomandibular joint (TMJ)
Explain how the masseter contributes to mastication.
elevates the mandible and therefore closes the mouth
Explain how the temporalis muscle contributes to mastication. (2)
anterior portion elevates the mandible and therefore closes mouth
posterior portion retracts mandible
Explain how the medial pterygoid muscle contributes to mastication.
elevates the mandible and therefore closes the mouth
Explain how the lateral pterygoid muscle contributes to mastication. (2)
bilaterally protracts mandible
unilaterally swings jaw to contralateral side for chewing movements
How does the mandibular division of the trigeminal nerve (CN V3) enter the infratemporal fossa?
through the foramen ovale
In what structure does the mandibular division of the trigeminal nerve (CN V3) give off its branches?
infratemporal fossa
List the (branchial) motor branches of the mandibular division of the trigeminal nerve (CN V3). (3)
4 nerves to muscles of mastication
mylohyoid nerve
nerves to tensor veli palatini and tensor tympani
The mylohyoid nerve provides innervation to which structures? (2)
motor innervation to mylohyoid muscle
motor innervation to anterior belly of digastric
The mylohyoid nerve is a branch of
the inferior alveolar nerve, which in turn is a branch of the mandibular division of the trigeminal nerve (CN V3)
List the general sensory branches of the mandibular division of the trigeminal nerve (CN V3).
auriculotemporal nerve
inferior alveolar nerve
mental nerve
long buccal nerve
meningeal branch
lingual nerve
What is the function of the inferior alveolar nerve? (3)
sensory innervation to lower dentition
gives off mylohyoid nerve
source of mental nerve
What is the mental nerve?
continuation of the inferior alveolar nerve after it exits mental foramen
What is the function of the mental nerve?
sensory innervation to chin region and lower lip
What is the function of the long buccal nerve?
innervates skin on lateral side of face overlying buccinator
innervates mucous membranes on medial aspect of buccinator
Which nerve provides motor innervation to the buccinator?
facial nerve
What is the function of the meningeal branch of the mandibular division of the trigeminal nerve (CN V3)?
sensory innervation of dura mater
What is the function of the lingual nerve? (3)
sensation of anterior 2/3 of tongue
carries taste fibers via chorda tympani
carries preganglionic parasympathetic fibers from chorda tympani to submandibular ganglion
What is an inferior alveolar nerve block?
anesthetic procedure used to block the inferior alveolar, lingual, and mental nerves in the lower dental quadrant to repair a cavity
What are the three parts of the maxillary artery? Identify their boundaries.
1st = posterior to lateral pterygoid
2nd = adjacent to lateral pterygoid
3rd = deep to lateral pterygoid
What arteries come off the first part of the maxillary artery?
inferior alveolar artery = into mandible = via mandibular foramen
middle meningeal artery = into cranial cavity = via foramen spinosum
What arteries come off the second part of the maxillary artery?
deep temporal artery = to muscles of mastication
What artery supplies the muscles of mastication?
deep temporal artery
What arteries come off the third part of the maxillary artery?
infraorbital artery = to orbit = via infraorbital foramen
What are the boundaries of the pterygopalatine fossa?
maxilla (anterior)
pterygoid process of sphenoid bone (posterior)
palatine bone (medial)
What depresses the mandible? (3)
gravity
suprahyoid muscles
infrahyoid muscles
Which muscles of mastication are not located in the infratemporal fossa?
masseter
temporalis
The TMJ is split into what two spaces? List the function of these two spaces.
articular disc splits TMJ into:
superior space = protraction and retraction
inferior space = elevation and depression
When is maximal depression of the TMJ achieved?
when protracted
List the connections of the pterygopalatine fossa. (6)
to orbit via orbital fissure
to middle cranial fossa via foramen rotundum
to pterygoid canal
to palate via greater/lesser palatine foramina
to nasal cavity via sphenopalatine foramen
to infratemporal fossa
How do preganglionic fibers travel to the pterygopalatine ganglion?
preganglionic parasympathetic fibers travel along with greater petrosal nerve (CN VII) to synapse at pterygopalatine ganglion
How do postganglionic fibers travel from the pterygopalatine ganglion?
travel with branches of maxillary division of trigeminal nerve (CN V2)
How does the maxillary division of the trigeminal nerve (CN V2), which provides sensory innervation, enter the skull?
via the foramen rotundum
Which nervous structures exit via the pterygopalatine fossa?
sensory branches from CN V2
postganglionic sympathetic fibers
postganglionic parasympathetic fibers
Where is the temporomandibular joint located?
between mandibular condyle and mandibular fossa of temporal bone
What kind of joint is the TMJ joint?
synovial joint (has an articular disc composed of fibrocartilage)
Which muscles protract the TMJ?
lateral pterygoid
Which muscles retract the TMJ?
posterior fibers of temporalis
Which muscles elevate the TMJ? (3)
anterior fibers of temporalis
masseter
medial pterygoid
Which muscles depress the TMJ?
suprahyoids
infrahyoids (initiate depression to open mouth)
lateral pterygoid
Which muscles produce side-to-side movements of the TMJ?
alternating, unilateral contraction of the lateral pterygoids
What is the significance of the pterygopalantine ganglion?
innervation to lacrimal and mucus glands
What is the pathway of innervation to the lacrimal glands via the pterygopalatine ganglion?
greater petrosal nerve (from CN VII) carries parasympathetic fibers through pterygopalatine canal
synapses with pterygopalatine ganglion
runs with branch of CN V2 (zygomatic nerve), then runs with branch of CN V1 (lacrimal nerve) to reach lacrimal gland
What is the pathway of innervation to the mucus glands via the pterygopalatine ganglion?
greater petrosal nerve (from CN VII) carries parasympathetic fibers through pterygopalatine canal
synapses with pterygopalatine ganglion
runs with branch of CN V2 to nasal cavity, palate, and pharynx
What is the function of the sympathetic fibers found in the pterygopalatine fossa? Give an example of a nerve associated with the sympathetic fibers of the pterygopalatine fossa.
vasoconstriction
[they do NOT synapse at the pterygopalatine ganglion, they synapse at superior cervical ganglion]
example: deep petrosal nerve
What is the relationship between the maxillary artery and the pterygopalatine fossa?
maxillary artery enters the pterygopalatine fossa, but its branches exit
What is the relationship between CN V2 and the pterygopalatine fossa?
maxillary nerve enters the pterygopalatine fossa, but its branches exit
Which structures (nerves and arteries) travel through the infraorbital fissure? (3)
infraorbital artery
infraorbital nerve
zygomatic nerve
Which structures (nerves and arteries) travel through the sphenopalatine foramen? (3)
sphenopalatine artery
nasopalatine nerve
posterior superior nasal nerve
Which structures (nerves and arteries) travel through the palatine canal? (5)
greater palatine artery
descending palatine artery
lesser palatine nerve
greater palatine nerve
lesser palatine artery
Which structures (nerves and arteries) travel through the pharyngeal canal? (2)
pharyngeal artery
pharyngeal nerve
Which structures (nerves and arteries) travel through the pterygoid canal? (2)
nerve of pterygoid canal
artery of pterygoid canal
Which structures (nerves and arteries) travel through the pterygomaxillary fissure? (2)
maxillary artery
posterior superior alveolar nerve
Which structures (nerves and arteries) travel through the foramen rotundum?
CN V2
What is the origin and insertion of the masseter?
origin = zygomatic arch
insertion = lateral side of mandibular angle
What is the origin and insertion of the lateral pterygoid?
origin = sphenoid
insertion = condylar neck of mandible + capsule of TMJ
What is the origin and insertion of the medial pterygoid?
origin = sphenoid
insertion = medial side of mandibular angle
