Trigeminal nerve is the largest cranial nerve. It arise from the ventral surface of the pons varolii. It bears a trigeminal ganglion at its origin and divides ito three branches.
(a) Opthalmic Nerve : It is the smallest branch of trigeminal nerve. It runs forward through the eye orbit and innervates the lacrimal glands, the conjunctiva of the eye, the forehead, the eye lids etc. It is sensory nerve.
(b) Maxillary Nerve : It innervates the cheeks, the upper gums, the upper teeth and lower eyelids. It is a sensory branch and carries stimuli from these areas.
(c) Mandibular Nerve : It is the largest branch of trigeminal nerve. It distributes nerve fibres to the teeth and the gums of the lower jaw, the pinna of the ear, lower lip and the tongue. It is a mixed branch having both sensory and motor fibres that help in controlling these particular organs.