Overview
Type
MotorSensoryAutonomic
Origin
Trigeminal ganglion of Gasser (sensory) + Motor nucleus of CN V (motor)
Exit skull
Foramen ovale → infratemporal fossa
Divisions
Anterior (smaller, mostly motor) · Posterior (larger, mostly sensory)
Sensory area
Lower ⅓ face, lower lip, mandible, preauricular/temporal skin, anterior ⅔ tongue, cheek, dura of middle cranial fossa
Motor muscles
Masticatory muscles, mylohyoid, anterior belly of digastric, tensor tympani, tensor veli palatini
Direct branches (pre-bifurcation)
Meningeal branch
= Nervus spinosus · re-enters skull via foramen spinosum · innervates dura mater of middle cranial fossa (follows middle meningeal artery)
N. to med. pterygoid
Innervates medial pterygoid, tensor tympani, tensor veli palatini
Posterior division
Auriculotemporal n.
Two roots encircle middle meningeal artery · parasympathetic from CN IX via otic ganglion to parotid · supplies tragus, EAM, tympanic membrane, temporal skin
Lingual nerve
Sensory Joins chorda tympani (CN VII) · anterior ⅔ tongue, floor of mouth, mandibular gingiva
Inferior alveolar n.
Enters mandibular foramen → mandibular canal → terminal branch = mental nerve (lower lip via mental foramen) · gives off N. to mylohyoid + ant. belly of digastric
Key associations to memorise
Nervus spinosus
= meningeal branch · spinosum = foramen it re-enters
Otic ganglion
Relay for parasympathetic fibers (CN IX → parotid gland via auriculotemporal)
Chorda tympani
CN VII branch that joins lingual nerve · carries taste + parasympathetic to submandibular/sublingual glands
Mental nerve
Terminal branch of inferior alveolar → exits mental foramen → lower lip
1st pharyngeal arch
All muscles motor-innervated by CN V3 derive from it