The maxillary nerve lies between the mandibular and ophthalmic nerves and is responsible for most of the feelings of sensation in the central region of the face, including the sinuses and nasal cavity. It is a branch of the trigeminal nerve, one of the 12 cranial nerves that control sensations in the face. The trigeminal nerve also has a limited amount of motor involvement, particularly the functions of biting, chewing, and swallowing.
The branch known as the maxillary nerve controls the sensations of the mid-face. The palate, or roof of the mouth, is supplied with nerve sensation by the maxillary nerve. This is also the nerve responsible for sensation in the nasal cavity.
The mandibular nerve, which sits on one side of the maxillary nerve, is the longest branch of the trigeminal nerve. This nerve provides nerve sensations to areas of the face such as the chin and lower lip. This is also the nerve responsible for the muscle movements involved in chewing and swallowing.
The ophthalmic nerve is another branch of the fifth cranial nerve. This nerve has various branches which supply such areas of the eye as the iris, cornea, and the ciliary body. The ophthalmic nerve also provides nerve sensations to the skin of the nose, forehead, eyelids, and eyebrows.
A primary function of the maxillary nerve is to transmit sensory signals from the the maxillary teeth to the area of skin between the mouth and upper eyelids. The maxillary nerve is also responsible for supplying the nerve sensations which travel between the sinuses and the nasal cavity.
Several medical conditions can affect the maxillary nerve, including trigeminal neuralgia. Sometimes caused by neurological disorders or simply arising as a natural part of aging, this condition causes moderate to severe pain in various areas of the face. Also known as tic douloureux, this condition can affect any or all of the areas of the trigeminal nerve. Treatment for the pain caused by trigeminal neuralgia generally begins with anticonvulsant medications, although other treatments such as alcohol injections or even surgical intervention may be explored, depending on the severity of the pain. Pain relief from this type of surgery often isn't permanent, and surgery can sometimes result in lasting nerve damage, leaving the face numb.