The Inferior Alveolar Nerve (n. alveolaris inferior; inferior dental nerve is the largest branch of the mandibular nerve. It descends with the inferior alveolar artery, at first beneath the Pterygoideus externus, and then between the sphenomandibular ligament and the ramus of the mandible to the mandibular foramen. It then passes forward in the mandibular canal, beneath the teeth, as far as the mental foramen, where it divides into two terminal branches, incisive and mental.
The branches of the inferior alveolar nerve are the mylohyoid, dental, incisive, and mental :
The mylohyoid nerve (n. mylohyoideus) is derived from the inferior alveolar just before it enters the mandibular foramen. It descends in a groove on the deep surface of the ramus of the mandible, and reaching the under surface of the Mylohyoideus supplies this muscle and the anterior belly of the Digastricus.
The inferior dental branches supply the molar and premolar teeth. They correspond in number to the roots of those teeth; each nerve entering the orifice at the point of the root, and supplying the pulp of the tooth; above the alveolar nerve they form an inferior dental plexus. They also give some branches (Inferior gingival branches) to the buccal gingiva of the manidublar teeth (except the first molar tooth)
The incisive branch is continued onward within the bone, and supplies the canine and incisor teeth.
The mental nerve (n. mentalis) emerges at the mental foramen, and divides beneath the Triangularis muscle into three branches; one descends to the skin of the chin, and two ascend to the skin and mucous membrane of the lower lip; these branches communicate freely with the facial nerve.
Two small ganglia, the otic and the submaxillary, are connected with the mandibular nerve.