Infratemporal Fossa Flashcards
What is the superior boundary of the infratemporal fossa?
infratemporal surface of the sphenoid bone
What is the anterior boundary of the infratemporal fossa?
Posterior aspect of the maxilla
What is the medial boundary of the infratemporal fossa?
Lateral pterygoid plate
What is the posterior boundary of the infratemporal fossa?
Tympanic plate, styloid, and mastoid processes
What is the lateral boundary of the infratemporal fossa?
Ramus of the mandible
What is the inferior border of the infratemporal fossa?
The medial pterygoid attachment to the mandible
What are the contents of the infratemporal fossa?
Muscles of mastication EXCEPT the masseter
V3 and associated autonomics
Maxillary artery and its branches
Pterygoid plexus of veins
Where will a sensory (afferent) neuron cell body be located in the CNS?
Dorsal horn nuclei
Where would a sensory (afferent) neuron cell body be located in the PNS?
Dorsal root ganglion
What is an example of a sensory afferent neuron cell body in the CNS?
Brainstem nuclei
What are the sensory ganglions in the PNS associated with sensory afferent neurons?
Trigeminal ganglion and geniculate ganglion
What is the sensory ending of the trigeminal ganglion?
pulp of tooth
What is the sensory ending of the geniculate ganglion?
taste bud
Where will the neuron cell body of a motor efferent neuron be located in the CNS?
Ventral horn nuclei
What is an example of a motor (efferent) nucleus in the CNS?
Motor nucleus of V
Motor nucleus of VII
What is the effector organ of motor nucleus V?
Masseter
What is the effector organ of motor nucleus VII?
Mentalis
What is the ONLY sympathetic ganglion in the PNS of the head and neck?
Superior Cervical Ganglion
Where are the neuron cell bodies of sympathetic neurons located in the CNS?
Lateral horn of T1-L2
Where are the neuron cell bodies of sympathetic ganglion, Superior Cervical Ganglion, located?
Lateral horn of T1-T4
What is the effector organ of the Superior Cervical Ganglion?
The smooth muscle associated with the maxillary artery
What are the neuron cell bodies associated with the parasympathetic (autonomic NS) that are located within the CNS?
Superior salivatory nucleus (VII) and inferior salivatory nucleus (IX)
With what ganglion will the superior salivatory nucleus synapse?
The submandibular ganglion
What is the effector organ of the superior salivatory nucleus -> submandibular ganglion 2-neuron parasympathetic system?
Submandibular and sublingual glands
With what ganglion will the inferior salivatory nucleus synapse?
Otic ganglion
What is the effector organ of the inferior salivatory nucleus -> otic ganglion parasympathetic (autonomic) 2-neuron system?
Parotid gland
Where does the motor root of the mandibular portion of the trigeminal nerve have its origin?
In the motor nucleus of V in the pons
Where are the sensory nerve cell bodies of the mandibular portion of the trigeminal neve located?
Trigeminal ganglion (semilunar, Gasserian)
What type of nerve is the trigeminal nerve, primarily?
Primarily a sensory nerve
How does the trigeminal nerve travel out of the skull?
Trigeminal passes through the foramen ovale
Of the entire trigeminal nerve, what part or parts have a motor division?
ONLY V3 (mandibular portion) has a motor division!!
What muscles does the motor portion of V3 supply?
The muscles derived from the first pharyngeal arch - the muscles of mastication + 4
What muscle will the anterior deep temporal nerve supply?
Temporalis
What muscle will the posterior deep temporal nerve supply?
Temporalis
What are the motor nerves of V3?
Anterior deep temporal Posterior deep temporal Masseteric nerve Medial pterygoid nerve Lateral pterygoid nerve Mylohyoid nerve Tensor Veli Palatini nerve
What muscles are innervated by the nerve to the mylohyoid?
The anterior belly of the digastric muscle, and the mylohyoid itself
Where will you find V3?
Right next to the lateral pterygoid muscle
What is the masseteric nerve a branch of, and how does it travel?
It is a branch of the deep temporal nerve and it travels OVER the masseteric notch
Where will you likely see the nerve to the mylohyoid?
The submandibular triangle
What are the branches of the sensory portion of V3?
Meningeal branch Auriculotemporal nerve Inferior alveolar nerve Mental Nerve Mylohyoid nerve Long buccal nerve Lingual nerve
What is the route of the meningeal branch of V3?
It will re-enter the skull through the foramen spinosum
What does the meningeal branch of V3 innervate?
it supplies a portion of the dura
What is the route of the auriculotemporal nerve?
It runs posterior, then lateral, then superior
It splits around the middle meningeal artery, and passes between the sphenomandibular ligament and neck of the mandible and supplies the TMJ
It will then pass posterior to the neck of the mandible and supply the parotid gland
And then it will pass anterior to the external ear, and supply part of it and the temporal region
Where are you likely to see the inferior alveolar nerve?
Between sphenomandibular ligament and ramus of the mandible
Where does the inferior alveolar nerve pass into, and travel in?
It passes into the mandibular foramen and travels in the mandibular canal
What are the branches of the inferior alveolar nerve?
The mental and incisive branches
What does the inferior alveolar nerve supply?
Mandibular teeth by dental arches and supporting structures (including PDL) by interdental branches to the midline
Where will the mental nerve exit the mandibular canal?
At about the 2nd premolar through the mandibular foramen
What will the mental nerve supply?
The facial gingiva over the incisors, canines, premolars (gingival branches), the skin of the chin (mental branches) and the lower lip (inferior labial branches)
Where will you find the long buccal nerve traveling?
Laterally between the two heads of the lateral pterygoid muscle
What muscle will the long buccal nerve pierce?
The buccinator
What does the long buccal nerve supply?
The sensory innervation of the skin of the cheek, facial gingiva over mandibular molars, and the mucosa of the cheek
Where will you find the part of the long buccal nerve that supplies the sensory innervations to the molar gingiva?
On the buccal shelf
Where will the lingual nerve be found?
Anterior and inferior to the alveolar nerve
Where does the lingual nerve enter the oral cavity?
Through triangle -
It will be found medial to the ramus of the mandible, inferior to the superior pharyngeal constrictor, and superior to the medial pterygoid muscle
What will the lingual nerve lie in contact with
The mandible at the lingual tuberosity in the third molar region
Where will the lingual nerve cross, loop, and cross again for it to get into the oral cavity?
It will cross the submandibular duct to the lateral
Loop under the duct and cross the submandibular duct to the medial
It will then travel farther anteriorly then go INTO the tongue
What does the lingual nerve supply?
General sensation to the anterior 2/3 of the tongue, lingual gingiva of ALL mandibular teeth, and the floor of the mouth (alveololingual sulcus) - to the midline
Where is the otic ganglion found?
Medial to V3 just outside of the foramen ovale
What is found synapsing at the otic ganglion?
Preganglionics from glossopharyngeal by way of the lesser petrosal nerve - preganglionic nerve cell bodies in the inferior salivatory nucleus
Where are the postsynaptics from the otic ganglion traveling to and with?
The postganglionic fibers travel to the parotid with the auriculotemporal nerve
The facial nerve provides motor innervation to what?
The 2nd branchial arch muscles: stapedius (in the ear), stylohyoid, posterior belly of digastric, muscles of facial expression
What type of fibers does the facial nerve have?
Motor, sensory, parasympathetic, and taste
Where will the facial nerve enter the petrous temporal bone?
Through the internal acoustic meatus
Where will the facial nerve lie within the petrous temporal bone?
The facial canal
What is the term for the sharp bend that the facial canal will make?
Genu (geniculum)
What is found at the genu of the facial canal?
The sensory ganglion for the facial nerve, the geniculate ganglion
What is given off at the genu of the facial canal?
A parasympathetic nerve branch - the greater petrosal nerve. It does not synapse at the geniculate ganglion, fibers just simply pass through it
What is the path of the facial nerve after the genu?
The facial nerve will pass over the middle ear, then downward and exit the skull through the stylomastoid foramen
What will happen to the facial nerve before it exits through the stylomastoid foramen?
It gives off a branch called the chorda tympani which passes upward toward the middle ear
What is the path of the chorda tympani?
It crosses the deep surface of the tympanic membrane, then through another canal to exit the skull through the petrotympanic fissue, just medial to the TMJ
What type of a nerve is the chorda tympani?
Preganglionic parasympathetic
What does the chorda tympani provide innervation to?
The sublingual and submandibular glands, as well as special sensory fibers for taste to the anterior 2/3 of the tongue
Where will the nerve cell bodies of the chorda tympani be found?
The superior salivatory nucleus
With whom will the chorda tympani “hitch a ride”
The lingual nerve
Where are the chorda tympani’s nerve cell bodies for taste?
The geniculate ganglion
Where is the submandibular ganglion found?
Just above the submandibular gland attached to the lingual nerve
What synapses at the submandibular ganglion?
Preganglionic parasympathetic fibers from the facial nerve
What is the sensory ganglia of the trigeminal nerve?
Geniculate ganglia
What is the parasympathetic ganglia of the glossopharyngeal nerve?
Otic ganglia
Otic ganglia
Preganglionic from inferior salivatory nucleus via lesser petrosal nerve
Postganglionic via the auriculotemporal to parotid
Submandibular ganglia is a parasympathetic ganglia to what nerve?
The facial nerve
Submandibular ganglia
Preganglionic from superior salivatory nucleus via the chorda tympani
Postganglionic directly to submandibular gland and via lingual nerve to sublingual gland
What divides the maxillary artery into 3 parts?
The lateral pterygoid muscle
What are the branches of the maxillary artery in the infratemporal fossa?
Deep auricular artery Anterior tympanic artery Middle meningeal artery Accessory meningeal artery Inferior alveolar artery Anterior temporal artery Deep temporal artery Masseteric artery Medial pterygo artery Lateral pterygo artery Buccal artery Posterior superior alveolar artery Infraorbital artery
What provides the primary blood supply to the TMJ?
Anterior tympanic artery (branch of maxillary artery)
Where will the accessory meningeal artery pass?
Foramen ovale
How will the maxillary artery end?
By entering into the pterygomaxillary fissure
What about the veins of the infratemporal fossa is different than the arteries?
The veins are the exact same as the arteries EXCEPT the veins have a pterygoid plexus
What connects the superficial and deep venous drainage in the infratemporal fossa?
The cavernous sinus
What is the pterygomandiular space?
A wedge shaped subspace of the infratemporal fossa - the base is superior and the apex is inferior
What are the boundaries of the pterygomandinular space?
Lateral boundary is the ramus of the mandible
Medial boundary is the pterygoid muscle
Superior boundary is the lateral pterygoid muscle
Posterior boundary is the interpterygoid fascia and the stylomandibular fascia
Anterior boundary is the pterygotemporal fascia
What are the contents of the pterygomandibular space?
Long buccal nerve - which will be found extremely anterior in the fascia on the medial aspect of the temporalis tendon Lingual nerve Inferior alveolar artery and vein Inferior alveolar nerve Sphenomandibular ligament Companion artery of the lingual nerve Auriculotemporal nerve (rarely)
What are the relationships to the pterygomandibular space?
Anterior is the oral cavity, medial is the lateral pharyngeal space, and posterior is the parotid fossa
