Which nerve is responsible for sensation to the face and mastication?

The trigeminal nerve is the primary nerve responsible for sensation in the face as well as the motor functions needed for mastication, or chewing. It is one of the twelve cranial nerves and has three main branches: the ophthalmic, maxillary, and mandibular nerves, each serving different areas of the face. The sensory function allows for the detection of touch, pain, and temperature, while the motor function of the mandibular branch specifically innervates the muscles involved in chewing.

The other nerves listed have distinct functions that do not involve both facial sensation and mastication. The facial nerve is primarily responsible for facial expressions and taste sensations from the anterior two-thirds of the tongue, rather than general facial sensation or mastication. The abducens nerve is involved in lateral eye movement, and the vestibulocochlear nerve is concerned with hearing and balance. Thus, the trigeminal nerve uniquely serves the dual role of sensory input and motor output for the face and chewing activities.