IT Fossa Flashcards
What are the boundaries of the IT Fossa?
Lateral: ramus of mandible
Medial: lateral plate of pterygoid process (sphenoid bone)
Anterior: Infratemporal surface of maxilla
Roof: greater wing of sphenoid
Superior: Zygomatic arch (superficial), IT crest on sphenoid (deep)
What artery is in the IT fossa? what are its branches?
1. Maxillary Artery (MID B PIGS) M: middle meningeal (to dura) I: Inferior Alveolar (gives off mylohyoidal branch) to jaw/gums.. lower teeth D: Deep Temporal (to temporalis) B: Buccal: To buccinator
P: Posterior Superior Alveolar (to gums/molars .. upper teeth)
I: Infraorbital (through infraorbital foramen) to
G: greater and Lesser palatine artery: Greater = hard palate, lesser = soft palate
S: sphenopalatine: in nose.. frequent cause of nosebleeds
what nerve innervates most of the structures in the IT fossa? It also runs in the IT fossa
V3 (mandibular) also thhttp://www.med.umich.edu/lrc/coursepages/m1/anatomy2010/html/index.htmle chorda tympanii of VII
what muscles are included in the IT fossa?
2/4 of the muscles of mastication (medial and lateral pterygoids)
the parotid duct goes through which muscle?
buccinator
which cranial foramen are found in the IT fossa
ovale (V3), spinosum (middle meningeal), external acoustic meatus, zygomaticofacial/temporal, alveolar (for inferior alveolar nerve/artery
what is the track of the inferior alveolar nerve??
it exits off of V3. Then it travels to lower teeth/gums through the mandibular foramen, and exits out of the mental foramen as the mental nerve
what does the mylohoid nerve branch off of? what does it innervate? What groove does it run through?
branches off of inferior alveolar nerve (V3), innervates the mylohyoid and anterior belly of the digastric (posterior belly is innervated by VII); runs through the mylohyoid groove in the inner mandible
what does the facial nerve innervate MOTOR? what are its branches? what are the facial artery branches?
innervates the muscles of facial expression (motor), stapedius, posterior belly of the digastric, stylohyoid + visceral motor to submandib, sublingual, lacrimal glands,
nerve branches: TZBMC (M = meningeal)
artery branches: inf. labia, sup. labia, lat. nasal, angular
where is the pterygoid plexus located?
between the medial and lateral plexus, and between the temporalis muscle and laterial pterygoid muscle
what runs between the tensor veli palatini muscle and levator veli palatini muscle?
superior pharyngeal constrictor
what is the clinical significance of the pterygoid plexus?
its connected to the cavernous sinus via emissary veins; thus infections from face, nasal, oral cavities and orbit can spread into the cranial cavity directly via the pterygoid plexus
where does the maxillary arter airse from?
the external carotid; posterior to the neck of the mandible
what is the course of the middle meningeal artery?
off of the maxillary art. medial to neck of mandible, courses superficially, goes through auriculotemporal circle/split, and then goes through the foramen spinosum (middle cranial fossa), to supply the dura
what is the course of the inferior alveloar artery?
follows inferior alveolar nerve path; goes through the mandibular foramen into the ramus and exits via mental foramen
where is the buccal artery located with respect to the buccinator muscle?
anterior
is the maxillary artery found anterior or posterior to the lateral pterygoid muscle?
can be either! 66% = superficial, 33% deep
what is the function of the anterior trunk of V3?
Motor EXCEPT the buccal nerve branch (sensory to cheek skin and second/third molar)
what is the function of the buccal branch off facial vs. V3?
Facial: MOTOR to buccinator
V3: SENSORY: to cheek skin and second/third molar
what is the function of the posterior trunk of V3?
Sensory EXCEPT nerve to mylohyoid (motor to mylohyoid + anterior belly of digastric)
what are the sensory branches of V3?
BAIL: Buccal Auricolotemporal I: inferior Alvelolar L: Lingual
what is the course of the lingual nerve? what cranial nerve does it come from? what division (ant/post) of V3 does it come from?
V3 POSTERIOR;
runs parallel and ANTERIOR to the inferior alveloar nerve (DOES NOT ENTER THE MANDIBULAR FORAMEN OR MANDIBLE IN GENERAL)
Enters the mouth next to the ramus of the mandible and runs parallel to the flood of mouth
PASSES UNDER MUCOSA BELOW THE THIRD MOLAR
what is the function of the lingual nerve?
general somatic sensory to anterior 2/3 of tongue, floor of mouth, lower gingiva