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4. Temporal, Infratemporal and Pterygopalatine Fossae


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What are the borders of the temporal fossa?
the temporal lines - swinging around from the zygomatic arch, swing around in a circle to the frontal process of the zygomatic bone (behind ear).
What are the contents of the temporal fossa?
Temporalis muscle and its neurovascular bundle.
What comprises the neurovascular bundle of the temporalis muscle?
-Mandibular branch of CN V
-Superficial temporal artery
What are the borders of the infratemporal fossa?
Lateral: medial edge of mandible ramus
Medial: Pharynx (soft tissue)
Superior: Skull base
Inferior: not distinct - blends into submandibular region.
What are the 4 contents of the infratemporal fossa?
1. TMJ
2. Muscles of mastication
3. Maxillary artery/branches
4. Mandibular branch of V3
What bones are involved in the TMJ?
-Condyle of the mandible
-Mandibular fossa of temporal bone
What covers the surfaces of the bones in the TMJ?
Articular cartilage
What resides inside the TMJ joint?
A capsule; divies the joint into superior/inferior synovial cavities.
What type of a joint is the TMJ?
What is a diarthrotic joint?
A Freely moving one.
What specific type of diarthrodial joint is the TMJ?
What does ginglymoarthrodial mean?
Ginglymo = hinge
Arthrodial = glide
Which compartments of the TMJ achieve the motions of:
Hinge = lower compartment

Glide = upper (angels glide high in the sky)
what is the purpose of the articular tubercle just in front of the TMJ?
To prevent anterior dislocation and bear the pressure from the joint.
How many ligaments are there in the TMJ?
What is the most lateral ligament in TMJ?
The lateral ligament (temporomandibular)
What does the lateral ligament connect exactly, and what is its function?
-Connects zygomatic arch to condyle neck.
-Restricts lateral deviation and retraction of the mandible.
What are the 2 medial ligaments?
What exactly does the Sphenomandibular ligament connect?
Spine of the sphenoid to the Lingula
what is the lingula?
Bony projection on medial side of ramus; covers the mandibular foramen. Houses the neurovasc bundle.
What is the function of the sphenomandibular ligament?
Restricts excessive depression (opening) of the jaw.
What does the stylomandibular ligament connect?
Styloid process on sphenoid, to the angle of the mandible.
What is the function of the stylomandibular ligament?
To resist excessive protrusion of the jaw.
How does the articular disc behave during TMJ motion?
-At rest, the disc is between articular surfaces.
-To slightly open, the disc slides down the anterior slope.
What action predominates in a
-Slightly open jaw
-Fully open jaw
Slight = hinge

Fully = hinge + gliding
What are 4 problems that can casue problems w/ the TMJ?
-Dental procedures that change the occlusion
-Arthritis of synovial joint
-Anterior dislocation
-Double-headed condyle
In what direction is the TMJ most commonly dislocated?
What is a usual cause of TMJ dislocation?
Trauma - does not tear the ligament though.
What are the true muscles of mastication?
Medial Pterygoid
Lateral Pterygoid
Temporalis muscle
Medial Pterygoid:
-Fiber orientation
Origin: medial side of lateral pterygoid plate
Insertion: medial aspect of mandible angle
Action: mandible elevation
Fibers: run superior-inferior
Lateral pterygoid:
Superior head Origin: greater wing of sphenoid
Inferior head origin: lateral side, lateral pterygoid plate.
What direction do the lateral pterygoid muscle fibers run?
Where do they insert?
anterior to posterior;
-Insertions: condylar neck of mandible and TMJ disc
What are 2 forms of contracting the lateral pterygoid muscle?
-Bilateral (both)
-Unilateral (one at a time)
What happens when lateral pterygoid muscles both contract?
Depression and protrusion of the mandible.
What happens when lateral pterygoids contract unilaterally?
Lateral deviation of the mandible to the contralateral side.
What function are the lat pterygoids crucial for?
Crushing/grinding food.
Where does temporalis muscle originate/insert?
Origin: temporal fossa
Insert: coronoid process of mandible.
In what 2 directions do temporalis fibers run, and what action does each do?
Anterior set: runs sup/inf and elevates jaw.
Posterior set: runs ant/post and retracts jaw.
Where does the Masseter originate from and insert?
Origin: Zygomatic bone/arch

Insertion: lateral aspect of mandibular angle
What is the masseter's action?
elevates the mandible
What is the 'NONtrue' muscle of mastication? What is it?
Buccinator - an accessory muscle that is classified as a muscle of facial expression.
What does the buccinator do in chewing?
Holds food between the molars.
What nerve is damaged if you can't keep food between your molars? What condition is this?
Facial nerve - CN VII

Bell's palsy
What are all the true muscles of mastication innervaetd by?
Cranial nerve V3
What major artery is in the infratemporal fossa?
the Maxillary artery
How much of opening the jaw do the lateral pterygoids accomplish?
Only the beginning of opening; completed by suprahyoids (mylohyoid, digastric, geniohyoid)
What are the 2 terminal branches of the external carotid artery?
-Superficial temporal
What's more important in the infratemporal fossa?
Into what 3 sections is the maxillary artery divided?
1. Mandibular
2. Muscular
3. Pterygopalatine
What 3 branches come from the Mandibular branch of the maxillary artery?
1. Deep auricular
2. Middle meningeal
3. Inferior Alveolar
What 3 structures does the deep auricular artery supply?
-Tympanic membrane
-External auditory meatus
What does the middle meningeal artery supply, and how does it get there?
Dura mater - runs through Foramen spinosum.
What does the inferior alveolar artery supply?
-Lower teeth
How does the inferior alveolar artery get to the mandible?
By running with the alveolar nerve; it exits the mental foramen to become the mental artery.
What are the 4 arteries of the muscular part of the maxillary artery?
1. Masseteric
2. Deep temporal aa (Ant/post)
3. Pterygoid arteries
4. Buccal
What important nerve is found in the infratemporal fossa?
The Mandibular branch of the Trigeminal nerve
Where does the mandibular V3 exit the skull?
Through foramen ovale
What are the 3 main regions of V3 mandibular nerve?
1. Main trunk
2. Anterior division
3. Posterior division
What angle are the branches of the Main trunk best seen from?
What are the 3 branches of the main trunk of V3 mandibular?
-Tensor veli palatini
-Tensor tympani
Where does the mandibular nerve exit the skull thruogh?
Foramen ovale
Where is the trigeminal ganglion located?
Right behind the pterygoid plate's foramen ovale.
Where are the main trunk branches given off?
-Tensor veli palatini and Tensor tympani right before going through foramen ovale
-Meningeal branch is given off right after exiting ovale.
What kind of nerves are the 3 branches of the main trunk?
Meningeal nerve = sensory
Tensor veli palatini = motor
Tensor tympani = motor
What does the meningeal nerve pass through to get to the dura?
Foramen spinosum
Which nerve can sometimes be a branch of the anterior division, and sometimes of the main trunk?
What kind of branch is it?
Medial pterygoid nerve; motor
In general terms what does the anterior division of V3 innervate?
-Muscles of true mastication
-Sensory via the buccal nerve
What are branches of the anterior division of V3?
-Lateral pterygoid
What does the buccal branch of V3 provide sensory info from?
-Buccal mucosa
-Buccal gingiva
-Skin over cheek
What is the buccal branch of V3 often confused with, and how do you differentiate them?
Buccal branch of CN VII (facial)
Facial buccal branch = MOTOR
Mandib buccal branch = SENSORY
What are the 3 terminal branches of the Posterior division of V3?
-Inferior alveolar
What kind of nerves are the posterior division branches?
-Auriculotemporal = sensory
-Lingual = sensory
-Inferior alveolar = mixed sensory AND motor
What does the auriculotemporal nerve recieve sensory info from?
-Auricle skin
-Temporal region
-External auditory meatus skin
What parasympathetic fibers are carried by the auriculotemporal nerve?
Postganglionic parasymp fibers from otic ganglion -> parotid gland
How do the preganglionic fibers get to the otic ganglion?
With the glossopharyngeal nerve, CN IX.
What does the lingual nerve deal with?
Sensory innervation
Where does the lingual nerve recieve sensory info from?
Anterior 2/3 of the tongue
What TYPE of sensory info does the lingual nerve obtain frmo the tongue's anterior 2/3?
-General sensory
-Special sensory
How does the Lingual nerve, a branch of V3, have taste fibers associated with it?
Because the Chorda Tympani nerve passes them along as it exits the tympanic cavity.
What else does the V3 Lingual nerve recieve from CN VII via the chorda tympani?
Preganglionic parasymp fibers going to the submandibular ganglion; then postganglionics go to submandib/sublingual glands.
What type of info does the inferior alveolar nerve carry?
Both motor and sensory
Where does the inferior alveolar nerve recieve sensory info from?
Then what happens to it?
The lower teeth; then terminates as mental nerve; sensory from skin of chin and lower lip.
What is the motor branch of the inferior alveolar nerve called, and what does it innervate?
Mylohyoid nerve:
-Anterior digastric muscles
So the inferior alveolar nerve terminates in what 2 nerves?
What will a tumor in the pterygopalatine fossa compress?
The maxillary nerve and artery
What are the borders of the pterygopalatine fossa?
Anterior: infratemporal surface of maxilla
Posterior: Pterygoid process of sphenoid
Medial: Vertical plate of palatine bone
Superior (roof): body of the sphenoid
Lateral: there isn't really one; just the pterygomaxillary fissure staring back at ya
How many openings are in the Pterygopalatine fossa?
What are they?
-Pterygomaxillary fissure
-Inferior orbital fissure
-Foramen rotundum
-Pterygoid canal
-Pharyngeal canal
-Sphenopalatine foramen
-Pterygopalatine canal
What passes through foramen rotundum and where is it wihtin the pterygopalatine fossa?
-Transmits CN V2 (maxillary)
-Most lateral hole on roof
What passes through the pterygoid canal and where is it wihtin the pterygopalatine fossa?
Transmits 3 things: CN VIII, nerve of pterygoid canal, and artery of pterygoid canal.
-middle opening on the roof.
What passes through the pharyngeal canal and where is it wihtin the pterygopalatine fossa?
-Transmits pharyngeal branch of maxillary artery and pharyngeal nerve.
-Most medial opening in roof.
What passes through the sphenopalatine foramen and where is it wihtin the pterygopalatine fossa?
-Transmits sphenopalatine artery and posterior superior nasal nerve
-On medial wall, leads to nasal cavity
What is the sphenopalatine artery?
The termination of the maxillary artery.
Where is the pterygopalatine canal and what does it lead to?
At the apex of the pyramid; leads to the palate.
What does the pterygopalatine fossa contain?
-Maxillary nerve (V2)
-Maxillary artery
What nerve carries preganglionic sympathetic fibers into the pterygopalatine fossa? Through what hole? From where?
Nerve of the pterygoid canal, from the nervous intermedius associated w/ CN VII
What happens to the preganglionic parasymp fibers from the nerve of the pterygoid canal?
They synapse at the pterygopalatine ganglion
Where do postsynaptic parasymp fibers go after synapsing at the pterygopalatine ganglion? (2 places)
-Via the Zygomatic nerve to nasal cavity glands
-Via the lacrimal nerve to the lacrimal gland.
What nerves are the Zygomatic and Lacrimal nerves branches of?
Zygomatic = V2 branch
Lacrimal = V1 branch (opthalmic)
What artery is contained in the pterygopalatine fossa?
The 3rd part of the maxillary artery - pterygopalatine part.
What do the pterygopalatine branches of the maxillary artery supply?
-Upper jaw
-Nasal cavity
What 2 vessels does the maxillary artery terminate in?
-Sphenopalatine arteries - going into the nasal septa
-Descending palatine artery in the pterygopalatine fossa
What does the descending palatine artery in the pterygopalatine fossa give off?
The greater/lesser palatine arteries, which pass through greater/lesser palatine foramen at the back of the palate.

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