Trigeminal Nerve 2 Flashcards
what is the course of the Mandibular Division of CNV?
CNV3 passes through the foramen ovale & into the infratemporal fossa
where is the foramen ovale located?
base of the greater wing of the sphenoid
what is the lateral boundary of the infratemporal fossa?
ramus of the mandible
what boundary lies medially to the infratemporal fossa?
lateral pterygoid plate of sphenoid bone
what is the anterior boundary of the infratemporal fossa?
posterior aspect of the maxilla
what boundaries lie posteriorly to the infratemporal fossa?
- tympanic plate
- mastoid process
- styloid process
what is the superior boundary of the infratemporal fossa?
infratemporal crest of sphenoid bone
what is the inferior boundary of the infratemporal fossa?
angle of the mandible
what is interesting about the mandibular division of the trigeminal nerve, differing it from the other divisions?
it has 3 trunks
what are the main branches of the mandibular division of the trigeminal nerve?
- auriculotemporal
- buccal
- mental
- lingual
- muscular
what are the different trunks of the mandibular division known as?
- main trunk
- anterior trunk
- posterior trunk
what nerves come from the Main Trunk of the Mandibular Division of CNV? note if they are motor or sensory:
- meningeal branch (sensory)
- branch to tensor tympani (motor)
- branch to tensor veli palatini (motor)
- nerve to medial pterygoid (motor)
where does the sensory meningeal nerve innervate?
dura mater
what nerves arise from the Anterior Trunk of the Mandibular Division of CNV? are they motor or sensory?
- deep temporal nerves (motor)
- nerve to lateral pterygoid (motor)
- masseteric nerve (motor)
- buccal nerve (*sensory)
what nerves arise from the Posterior Trunk of the Mandibular Division of CNV? are they motor or sensory?
- auriculotemporal nerve (sensory)
- lingual nerve (sensory)
- inferior alveolar nerve (MIXED motor & sensory)
what are the areas of distribution of the mandibular division?
- auricle
- temple
- cheek (posteriorly or laterally)
- lower lip
- chin
- floor of mouth & lower teeth
- anterior 2/3 tongue
where does the auriculotemporal nerve innervate? what type of innervation does this nerve supply?
sensory innervation to posterior temple/side of head
where does the buccal nerve innervate? what type of innervation does this nerve supply?
sensory innervation to the lateral posterior area of the cheek & posterior buccal gingivae of molars
where does the mental nerve innervate? what type of innervation does this nerve supply?
sensory innervation to the lower lip & buccal gingivae of anterior teeth (premolar onwards)
what nerve does the mental nerve arise from?
a branch of the inferior alveolar nerve (posterior trunk)
where does the mental nerve emerge?
the mental foramen
what disorder may cause terrible pain to arise in CNV3? (occasionally in CNV2 as well)
trigeminal neuralgia
what Trunk of the Mandibular Division supplies general sensory innervation to the oral cavity?
posterior trunk
what nerve supplies sensory innervation to the cheek & posterior buccal gums?
buccal nerve
what nerve supplies the lower posterior teeth? (from molars up to second premolar)
main trunk of inferior alveolar nerve
what nerve supplies the lower anterior teeth? (1st premolar to central incisor)
incisive branch of inferior alveolar nerve
what nerve supplies the skin of chin & lower lip, as well as anterior buccal gingivae?
mental nerve branch of the inferior alveolar nerve
what is interesting about the inferior alveolar nerves innervation?
before entering the mandibular foramen, the inferior alveolar nerve fibres are MIXED (both sensory and motor)
what occurs before the mixed inferior alveolar nerve enters the mandibular foramen?
a branch splits off, this is the nerve to mylohyoid (MOTOR FIBRES)
when the inferior alveolar nerve enters the mandibular division, how does its innervation change?
only SENSORY innervation once it enters the spongy bone (through mandibular foramen)
what does the nerve to mylohyoid supply?
motor innervation to the mylohyoid & anterior belly of digastric
what nerve supplies the lingual gingivae?
lingual nerve
what is meant by general sensation?
- pressure
- temperature
- pain
etc.
what is meant by special sensation in relation to oral cavity?
taste
what does the lingual nerve innervate? what type of innervation is this?
provides general sensory sensation to the anterior 2/3rd of the tongue
what nerve supplies special sensation to the anterior 2/3rds of tongue?
CNVII (7) facial nerve
what nerve innervates the muscles of mastication?
CNV3 motor roots
what are the different muscles of mastication?
- lateral pterygoid muscle
- medial pterygoid muscle
- masseter muscle
- temporalis muscle
what other muscles (aside from muscles of mastication) does CNV3 supply?
- tensor tympani (middle ear)
- tensor palati
- mylohyoid
- anterior belly of digastric
what is the jaw jerk reflex?
- involves sensory information being passed through the trigeminal nerve into the mesencephalic nucleus (of the trigeminal nerve) which deals with proprioception
- it then connects to the motor nucleus of the trigeminal of the pons
- info sent to muscles
what is the skin over the angle of the mandible supplied by?
the cervical plexus of the great auricular nerve (cranial nerve 2 & 3)
what is shingles?
reactivation of varicella zoster virus in the trigeminal ganglion
what are the clinical symptoms of shingles/
- erythematous, vesticular, crusting rash
- burning sensation
what is Hutchinson’s sign?
cutaneous involvement of the tip of the nose (external nasal branch of nasociliary nerve)
what does a positive Hutchinson’s sign increase the chance of?
the likelihood of ocular complications
- conjunctivitis
- keratitis (cornea)
- uveitis
what does the facial nerve supply?
the muscles of facial expression
