Infratemporal Fossa, Maxillary Artery, Muscles of Mastication and V3 Flashcards
What is the only trigeminal division that carries both motor and sensory?
V3 mandibular branch
What are the CN that are general visceral efferents and parasympathetics? How do these travel to the head?
3,7,9,10 and they travel by jumping onto 5 to get to their target
What makes up the temporal region?
the temporal and infratemporal areas
Where do you find the infratemporal fossa?
deep to the mandible and inferior to zygomatic arch
What is the anterior boundary of the infratemporal fossa?
What is the medial boundary of the infratemporal fossa?
What is the lateral boundary of the infratemporal fossa?
What is the posterior boundary of the infratemporal fossa?
maxillary bone
lateral pterygoid plate
ramus
parts of temporal bone
What is the infratermporal fossa continuous with?
the temporal fossa
What is the inferior border of the infratemporal fossa?
there isnt one, it is actually open but the medial pterygoid muscle holds it in place
What do you call the point between the body and the ramus of the mandible?
the angle of the mandible
What the space between the mastoid process and styloid process? What passes through this?
the styloidmastoid foramen
CN 7
Once CN7 passes through the styloidmastoid foramen, what kind of fibers does it mainly carry? What does it give off here?
motor
5 terminal branches of facial expression (temporal, zygomatic, buccal, mandibular, cervical)
What is the fissure between the pterygoid plate and the maxilla? Why is this significant?
the pterygomaxillary fissure
this is how things get into and out of the Pterygopalatine fossa
What artery runs from the infratemporal fossa through the pterygomaxillary fissure and through the pterygopalantine fossa?
the terminal branch of the maxillary artery called the pterygopalatine portion or 3rd portion
So the foramen ovale and the foramen spinosum are wildly important, because one of the foramen has something neat coming out of the cranium and one has something neat going into the cranium….what are they?
coming out of the foramen ovale is the V3 (mandibular) nerve
going into the foramen spinosum is the middle meningeal artery
Once the mandibular nerve (v3) comes out of the foramen ovale, where does it go?
into the infratemporal fossa :)
What are the lateral and medial pterygoid plate a part of?
the sphenoid bone
where is the mandibular fossa?
underneath the zygomatic process where it meats the condylar process
What are four bony structures found on the mandible?
condylar process (articulation w/ temporal bone) mandibular notch (below condylar process) mandibular foramen (place for anesthesia) coronoid process (crown next to mandibular foramen)
What is the TMJ?
temporomandibular joint
What do you find in the mandibular foramen and why is this significant?
you find the blood vessels and nerves to the mandible i.e. nerve supply to lower teeth (important for anesthesia)
How many joint cavities does the TMJ have and what are they?
2 cavities
superior joint cavity, a disc and inferior joint cavity
Explain the composition of the TMJ?
superior joint cavity, a disc, inferior joint cavity surrounded by strong ligamentous capsule. With a muscle that attaches from the condyle (of the mandible) to the disc.
What is the muscle called that connects the condyle (of mandible) to the disc of the TMJ?
the lateral pterygoid muscle (a muscle of mastication)
What does the lateral pterygoid muscle do?
it pulls both the condyle (of mandible) and the disc of the TMJ anteriorly
What happens when you open your jaw to your mandibular joint?
the mandibular condyle will move forward anteriorly on the mandibular fossa and then ride over the articular tubercle
What happens if you open your jaw too wide (i.e extreme protraction)?
you will move your condyle too far anteriorly and roll of the articular tubercle and thus into the space where your strong muscles of mastication are which will cause uniform contraction and prevent the return of the condyle to its previous location. To fix this you must use muscle relaxants and shove it back into place.
How do you open your jaw fully?
extreme protraction
Slight elevation and depression of your jaw happens as a (blank) movement.
hinge movements
How do you create grinding motions (side to side)?
elevation, depression, protraction and retraction
T or F
Can you protract on one side and retract on the other at the TMJ?
yes!
What are the 2 ligaments of TMJ that get taught as the jaw pulls forward and what do they do?
the sphenomandibular ligament
stylomandibular ligament
limit excess opening of the mandible
What is the main protractor of the mandible and how does it do this?
the lateral ptergyoid muscle It has two heads one pulls the condyle towards the ptergyoid plate and the other head yanks on the articular disc to open the jaw
So what do the two heads of the lateral ptergyoid muscle attach to?
One head-> condyle
second head-> articular disc
What connects the temporal bone to the mandible?
the joint capsule (fibrous CT)
Where do you find the synovial membrane within the joint capsule of the TMJ?
non-weight bearing surfaces
Where do you find hyaline cartilage in the TMJ?
articular surfaces
Betweeen the articular disc and the mandibular fossa (temporal bone) of the TMJ, what kinds of movements do you get here?
gliding movements
Between the articular disc and the hyaline cartilage of the condylar process of the TMJ, what kinds of movements do you get here?
hinge movements
Is the TMJ a stiff joint or does it have a large range of motion?
What does this mean?
large range of motion
very susceptible to dislocation
If you pass in anterior to the articular tubercle, what do you have?
jaw dislocation
What three general classifications of things do you find in the infratemporal fossa?
muscles of mastication
branches of mandibular nerve
branches of maxillary artery
What kinds of fibers do we need for muscles of mastication?
branchiomotor (SVE)
Describe the fibers found on CN V
it is a sensory nerve except for V3 which is also branchiomotor
Muscles of mastication all stem from (blank) and what gives motor innervation to them?
first branchial arch
CN 5 V3 (only division that carries motor in addition to sensory)
What is the most superifical muscle of mastication right underneath the skin?
masseter
What is a powerful elevator of the mandible (closes the jaw) and what plane is is the origin and insertion in? What does this mean about its movments?
the masseter
both in the same sagittal plane
its gonna kick ass at going up and down but sort of suck at going side to side.
What is the origin the masseter?
What is the insertion of the masseter?
zygomatic arch
ramus and angle of mandible
What do the anterior fibers of the temporalis muscle do?
How are the fibers oriented?
they contribute to elevation of the mandible and jaw closing
vertically oriented
What do the posterior fibers of the temporalis muscle do?
How are the fibers oriented?
contribute to retraction of the mandible and jaw closing horizontally oriented (good at grinding)
The temporalis muscle and massater muscle are both innervated by what and do what?
V3 of CN5
they are muscles of mastication
which pterygoid muscle parallels the orientation of the masseter?
the medial pterygoid muscle
What is the muscle that has horizontal fibers and goes from the lateral border of the maxilla to the teeth? What kind of muscle is it? What innervates it?
buccinator
facial expression muscle
CN 7
What do you find going through the buccinator and where does it come from?
the parotid duct (entering right by the second upper molar) from the parotid gland :)