Trigeminal nerve

The trigeminal nerve (V) is a mixed cranial nerve with a large sensory component and a smaller motor component. It provides most of the general sensory innervation of the head and face and motor innervation to muscles involved in mastication.

Number : V

Sensory, motor, or both : both, predominantly sensory

Origin : the nerve emerges from the pons, just caudal and ventral to the point where the transverse fibers of the pons continue dorsally as the middle cerebellar peduncle, rostral to the lateral end of the trapezoid body.

Route / Reports : the trigeminal nerve enters the trigeminal canal on the rostomedial aspect of the petrous part of the temporal bone. Within this canal lies the trigeminal ganglion. As the nerve emerges from the trigeminal canal, it divides into three major branches: the ophthalmic nerve, maxillary nerve, and mandibular nerve.

Distribution : the ophthalmic nerve is sensory; the maxillary nerve is sensory; and the mandibular nerve is both sensory and motor. Together, these branches supply extensive sensory innervation to the head and face, while the mandibular division provides motor innervation to muscles involved in mastication.

Description : The trigeminal nerve emerges from the pons and enters the trigeminal canal of the petrous temporal bone, where the trigeminal ganglion contains the sensory neuronal cell bodies. It then divides into three major branches: ophthalmic, maxillary, and mandibular. The ophthalmic and maxillary nerves are sensory, whereas the mandibular nerve contains both sensory and motor fibers.