lingual nerve is a branch of the
mandibular nerve (CN V3), itself a branch of the trigeminal nerve.The lingual nerve supplies sensory innervation to the
mucous membrane of the anterior two-thirds of the tongue.It also carries nerve fibers that do not originate from the trigeminal nerve, including taste sensation to the anterior part of the tongue as well as
parasympathetic and sympathetic fibers.The
submandibular ganglion is suspended by two nerve filaments from the lingual nerve.
Path
The lingual nerve lies at first beneath the
lateral pterygoid muscle, medial to and in front of the inferior alveolar nerve, and is occasionally joined to this nerve by a branch which may cross the internal maxillary artery.The
chorda tympani (a branch of the facial nerve, CN VII) joins it at an acute angle here, carrying taste fibers from the anterior two thirds of the tongue and parasympathetic fibers to the submandibular ganglion.The nerve then passes between the
medial pterygoid muscle and the ramus of the mandible, and crosses obliquely to the side of the tongue over the Constrictor pharyngis superior and Styloglossus, and then between the Hyoglossus and deep part of the submandibular gland; it finally runs across the duct of the submandibular gland, and along the tongue to its tip becoming the sublingual nerve, lying immediately beneath the mucous membrane.