Temporal Region: Muscles of Mastication Flashcards
what are the 4 true muscles of mastication
temporalis, masseter, medial and lateral pterygoid
what are the 4 accessory muscles of mastication
digastric muscle, buccinator, tongue muscles and orbicularis oris
what are the 3 jaw closers
temporalis, masseter, and medial pterygoid
what is the jaw protractor
the lateral pterygoid
what is the jaw opener muscle
digastric muscle
where does V3 mandibular nerve emerge into
the infratemporal fossa
what are the 3 sensory parts of V3 mandibular nerve
inferior alveolar nerve: lower jaw and teeth, buccal nerve: interior mouth, and lingual nerve: anterior 2/3 tongue
what are the 2 motor parts of V3 mandibular nerve
muscles of mastication and tensor veli palatine muscle and nerve to mylohyoid: anterior belly of digastrics and mylohyoid muscle
what parasympathetics from CN7 do V3 carry
preganglionic parasympathetics from chorda tympani to submandibular ganglion and lingual nerves to submandibular and sublingual glands
what are the 4 movements of the temporomandibular joint
depression, elevation, protrusion, and retraction
what innervates the anterior belly of the digastric muscle
mandibular V3 nerve
what innervates the posterior belly of the digastric muscle
facial nerve 7
what are the 3 cranial nerves involved in general sensation of mastication
maxillary nerve (V2), mandibular nerve (V3) and glossopharyngeal nerve (9)
what motion does mastication involve
a roughly circular jaw motion
what does the maxillary nerve V2 give sensation to
hard palate and upper teeth
what does the mandibular nerve (V3) give sensation to
sensory from anterior 2/3 of tongue and lower teeth
what does the glossopharyngeal nerve (CN9) give sensation to
sensory from posterior 1/3 of tongue
how does the jaw open/depress
with gravity and neck muscles
how does the jaw protrude
the mandibular condyle slides anteriorly by the lateral pterygoid (CN V3)
what helps position the food
tongue (CN 12) and cheek muscles (buccinator CN7)
how does the jaw contract/move towards the chewing side
by contraction of the chewing side masseter (CN V3) and contralateral medial pterygoid (CN V3)
what happens with the power stroke
the jaw elevates (masseter, temporalis, and medial pterygoid) and the jaw moves toward the non-chewing side (contralateral masseter, chewing side medial pterygoid)
what are the 3 ligaments that support the mandible and limit the TMJ ranges of motion
sphenomandibular, temporomandibular, and stylomandibular
how many synovial cavities are in the TMJ
two: superior and inferior synovial cavities
where is the condyle when the jaw is closed
below the fossa
where is the condyle when the jaw is opened
under the tubercle
what 2 actions are required for a full gap opening
both sliding and hinge actions
what are 3 symptoms of TMJ dysfunction
pain in preauricular region and muscles of mastication, limit range of movements, and clicking sounds
