The Lingual nerve is a branch of the mandibular division of the trigeminal nerve (V3). It lies anterior to the inferior alveolar nerve beneath the inferior margin of the lateral pterygoid. The lingual nerve crosses the submandibular duct twice. The lingual nerve innervates the mucous membranes covering the anterior 2/3 of the tongue and the floor of the mouth with tactile sensation. It provides taste sensation through the fibers derived from the chorda tympani.
The lingual nerve may be damaged during tonsillectomy or extraction of an impacted third molar tooth.