Temporal and Infratemporal Fossa Flashcards
What does the mandibular foramen conduct?
the inferior alveolar a. and n.
What is the lingula?
a small spine that serves as an attachment point for the sphenomandibular ligament
Is the sphenomandibular joint medial or lateral to the TMJ?
medial (attachment at the lingula)
Where does the stylomandibular ligament run?
medial to the TMJ; it passes from the styloid process
to the posterior margin of the ramus and angle of mandible
Where does the lateral ligament run?
from the articular tubercle on the zygomatic arch to the neck of the mandible
What bones make up the floor of the temporal fossa?
Frontal, parietal, temporal, and greater wing of the sphenoid.
A rupture of the preteen might damage which important artery?
the middle meningeal a.
What is the anterior border of the infra temporal fossa?
infratemporal surface of the maxilla
What is the posterior border of the infra temporal fossa?
temporal bone including vertical plane of styloid process
What is the superior border of the infra temporal fossa?
infra temporal surface and crest of the greater wing of the sphenoid bone
What is the medial border of the infra temporal fossa?
lateral pterygoid plate
What is the lateral border of the infra temporal fossa?
ramus of mandible.
NOTE: The inferior boundary is really just the place where some of the muscles in this space come together
What is the lateral opening into the pterygopalaIne fossa?
the pterygomaxillary fissure
What does the pterygomaxillary fissure conduct?
the maxillary artery
What are the main contents of the infra temporal fossa?
muscles of mastication, mandibular nerve(V3) and its
branches, maxillary artery and its branches, and the pterygoid plexus of veins and maxillary vein.
What does the foramen spinosum conduct?
the middle meningeal a. and n.
Where does the temporalis m. insert?
on coronoid process of mandible
What do the anterior and medial fibers of temporalis do?
help to elevate the mandible
What do the posterior fibers of temporalis do?
horizontal in orientaIon – these help retract the mandible.
What is the function of the masseter?
FuncIons in elevaIon of the mandible.
Where does the upper head of the lateral pterygoid originate? Insert?
originates from the infratemporal crest and inserts into the articular disk
Where does the lower head of the lateral pterygoid originate? Insert?
originates from the lateral surface of the lateral pterygoid plate and inserts into the condyle.
What is the function of the lateral pterygoid?
The lateral PT is involved in jaw protrusion.
Where does the medial pterygoid originate? insert?
originates from the medial surface of lateral PT plate of the sphenoid , as well as from infratemporal surface of maxilla, and inserts into deep angle of the mandible
What is the function of the medial pterygoid?
medial PT elevates the mandible. Medial and lateral pterygoids also funcIon in side-to-side movements of the jaw during mastication
The muscles of mastication are all innervated by which n.?
the anterior branch of the mandibular n.
What divides the TMJ into upper and lower portions?
the articular disc
What is the upper portion of the TMJ responsible for facilitating? The lower portion?
upper compartment for gliding movements involved in wider jaw opening (protrusion), and a lower compartment for a more simple hinge movement to open jaw (depression).
What muscle does the temporal fascia overlie?
the temporalis. It runs superiorly from the zygomatic arch
What fascia connect the investing fascia of the neck with the temporal fascia at the zygomatic arch?
the masseteric fascia from the mandible to the zygomatic bone/arch
Posteriorly, what is the mastered fascia continuous with?
the parotid fascia
Where does the temporal fascia insert superiorly?
at the superior temporal line. It consists of both superficial and deep layers. These layers attach to both the medial and lateral surfaces of the zygomaIc arch.
What muscle does the posterior auricular a. run over?
the posterior digastric m.
What two fossa does the maxillary a. run through?
the infra temporal fossa and the pterygopalatine fossa
The course of the maxillary a. is divided into three parts based on its relation to what?
the lateral pterygoid
What are the three segments of the maxillary a.?
the maxillary and pterygoid (in the infra temporal fossa) parts and the third part in the pterygopalatine fossa
the maxillary part of the maxillary a. runs where?
forward deep to the neck of the mandible, and runs along the lower border of the lateral pterygoid muscle
Most of the branches of the maxillary part of the maxillary a. exit the ITF how?
via bony communicaIons (e.g. foramen spinosum, mandibular foramen, etc.)
How does the pterygoid segment of the maxillary a. run?
adjacent (tends to be superficial and deep at different points) to the lateral PT muscle. Its branches are predominantly muscular branches
What are the branches of the maxillary part of the maxillary a.?
deep auricular, inferior alveolar, middle meningeal, accessory meningeal, and anterior tympanic branches
What does the anterior tympanic branch of the maxillary a. supply?
the internal aspect of the tympanic membrane in the ear
What does the deep auricular branch of the maxillary a. supply?
the EAM, external tympanic membrane and TMJ
How does the inferior alveolar a. run and what does it supply?
This artery branches off maxillary inferiorly and enters the mandibular foramen and canal with the inf. alv.
nerve. It supplies the mandible and all lower teeth. After it travels the length of the mandible it will emerge with the nerve through the mental foramen to supply the chin and lower lip as the mental artery.
How does the middle meningeal a. re-enter the cranial cavity?
via foramen spinosum
What does the middle meningeal a. supply?
to supply periosteum, bone, dura mater of lateral wall and calvaria of neurocranium, tympanic cavity and tensor tympani muscle
How does the accessory meningeal a. re-enter the cranial cavity?
foramen ovale
What are the branches of the pterygoid part of the maxillary a.?
Masseteric, 2 pterygoids, external buccal, and an anterior and posterior deep temporal branches.
What does the buccal branch of the prettied part of the maxillary a. do?
The buccal artery runs anteriorly and inferiorly with the buccal nerve (divisionof V3) to supply the buccal fat pad, buccinator, and buccal oral mucosa.
Prior to passing through the foramen spinosum, the middle meningeal artery often passes through a loop formed by what?
branches of the auriculotemporal nerve
The pterygoid vein plexus is located partly between which muscles?
the temporalis and pterygoid muscles.
The pterygoid plexus drains to which vein?
the maxillary vein
What are some of the main connections of the pterygoid plexus?
The plexus anastomoses superiorly with the cavernous sinus through emissary veins and anteriorly with the facial vein through the deep facial vein and with the ophthalmic v.
What is the chorda tympani branch of the facial n. responsible for doing?
parasympatheIcs to the submandibular and sublingual glands, and also carries taste informaIon from the anterior 2/3 of the tongue
The auricotemporal n. runs with which a.?
Runs along upper most part or margin of paroId gland, turns upward over the arch with sup. temp. artery and distributes to scalp in front of ear
Describe the course and branching of the inferior alveolar n.
Traversing the mandibular canal,the inferior alveolar nerve provides inferior dental branches which form the inferior dental plexus.
- This plexus supplies the molar and premolar teeth. Note there is a small incisive branch of inferior alveolar that supplies the canine and incisor teeth.
- The inferior alveolar then emerges from the mental foramen to become the mental nerve
What are the taste buds of the soft palate innervated by?
the greater petrosal nerve
What provides innervation to the soft palate (besides the soft palate)?
the facial
Where is the geniculate ganglion located?
just inside the IAM
Describe the full distribution of the facial n.
The facial n. arises in the cranial cavity and consists of both motor and sensory portions. The BE and GVE portions have preganglionic cell bodies in the brainstem and GSA and SA cell bodies are located in the geniculate ganglion in the IAM.
The motor and sensory parts of the facial nerve enter the IAM where they immediately encounter the geniculate ganglion. Only the sensory parts synapse with the cell bodies there, the BE and GVE components pass in tight communication with the ganglion
From the geniculate ganglion, the greater petrosal nerve is given off through the hiatus for the greater petrosal n. into the cranial cavity, travels in the petrosal groove toward the carotid foramen in the middle cranial cavity, and unites with the deep petrosal n. (conveying postganglionic sympathetics from the external carotid) over the foramen lacerum and then together they enter the petrosal canal and together become the nerve of the petrosal canal and synapse in the posterior part of the pterygopalatine ganglion. From the PP ganglion, postganglionic fibers travel with (? branches of the maxillary n.) to provide GVE parasympathetics to the lacrimal gland and there are also SA (not running with a branch of CN V) to the taste buds of the soft palate.
Near the end of the facial canal, the chorda tympani is given off via the bony canal to the tympanic cavity. The nerve passes over the medial surface of the tympanic membrane, arches across the malleus, and leaves the tympanic cavity near the anterior border of the membrane. Once past the tympanic cavity, the chorda tympani goes through the petrotympanic fissure to emerge inferiorly from the skull where it then joins with the lingual nerve high in the ITF to travel to the mouth to provide GVE to the submandibular and sublingual glands (via the submandibular ganglion) and SA to the anterior 2/3 of the tongue. This is a unique example of PREganglionic GVE parasympathetic fibers running with a branch of CN V.
Once the facial n. exit the SMF, it gives off GSA fibers (cell bodies in the geniculate ganglion) to the external ear, BE motor fibers of the facial n. (temperofacial and cervicofacial branches), and BE motor branches to the posterior digastric and stylohyoid
Sympathetics to the submandibular and sublingual glands are distributed via what?
distributed locally via lingual and facial artery.
