Introduction
The lingual nerve is a mixed nerve located in the human head and neck. It is a branch of the posterior trunk of the mandibular nerve and is the main sensory nerve of the tongue. It supplies sensation to the tongue, as well as to the mucous membrane and skin of the floor of the mouth. Knowledge of the anatomy of this nerve is important for dental surgeons, as it is often damaged during dental procedures.
Anatomy
The lingual nerve is a branch of the posterior trunk of the mandibular nerve, a branch of the trigeminal nerve. It exits the skull through the foramen ovale and enters the infratemporal fossa. It runs posteriorly between the medial pterygoid muscle and the ramus of the mandible. It then passes anteriorly to the superior constrictor muscle and the medial pterygoid muscle. It then enters the floor of the mouth, where it divides into two main branches: the lingual nerve proper and the nerve to mylohyoid.
The lingual nerve proper passes anteriorly to the submandibular gland and the hyoglossus muscle. It then divides into a medial and a lateral branch. The medial branch supplies sensation to the anterior two-thirds of the tongue, while the lateral branch supplies sensation to the posterior one-third of the tongue.
The nerve to mylohyoid passes anteriorly to the submandibular gland and the hyoglossus muscle. It then divides into two branches: the nerve to the mylohyoid muscle and the nerve to the anterior belly of the digastric muscle. The nerve to the mylohyoid muscle supplies motor fibers to the mylohyoid muscle, while the nerve to the anterior belly of the digastric muscle supplies motor fibers to the anterior belly of the digastric muscle.
Clinical Significance
Damage to the lingual nerve can occur during a variety of dental procedures, including dental extractions, implant placement, and dental restorations. Damage to the lingual nerve can result in numbness or paresthesia of the tongue, as well as the floor of the mouth. In severe cases, damage to the lingual nerve can result in permanent loss of sensation in the affected area.
Conclusion
In conclusion, the lingual nerve is a mixed nerve located in the head and neck. It is a branch of the posterior trunk of the mandibular nerve and supplies sensation to the tongue, as well as to the mucous membrane and skin of the floor of the mouth. Damage to the lingual nerve can occur during a variety of dental procedures, and can result in permanent loss of sensation in the affected area.
References
Ganeles, J. (2017). The Lingual Nerve: Anatomy, Clinical Significance, and Prevention Strategies. The Journal of Oral Implantology, 43(4), 287–293. https://doi.org/10.1563/aaid-joi-D-16-00103
Takasaki, Y., Tajima, S., Takahashi, K., & Takahashi, T. (2016). Anatomy of the lingual nerve. International Journal of Oral and Maxillofacial Surgery, 45(3), 340–345. https://doi.org/10.1016/j.ijom.2015.12.002