Nervus lingualis: applied anatomical relevance to dental practice and oral surgery.

N. lingualis supplies general sensory branches to the mucosa of the anterior two-thirds of the tongue, sublingual mucosa and the mandibular lingual gingiva. From an oral surgery point of view, the course of the lingual nerve is critical due to the intimate medial relationship to the roots of the mandibular third molar. "Hitch-hiking" special sensory taste fibres from the chorda tympani (cranial nerve seven) are distributed to the mucosa of most of the anterior two-thirds of the tongue, together with the general sensory branches derived from the mandibular division of the trigeminal nerve. The circumvallate papilLae anterior to the sulcus terminalis are supplied by special sensory fibres (taste) of the glossopharyngeal nerve, latrogenic lingual nerve injury, subsequent to mandibular wisdom teeth removal, can result in irreversible gustatory deficits and somatosensory dysfunction. Patients undergoing oral surgery for impacted mandibular molars should be informed of the anatomical relationship of the lingual nerve to the roots, and the implications of denervation.