Communication Between the Mylohyoid and Lingual Nerves: Clinical Implications

The mylohyoid muscle plays an important role in chewing, swallowing, respiration and phonation, being the mylohyoid nerve also closely related to these important functions. It has been postulated that the mylohyoid nerve might have a role in the sensory innervation of the chin and the lower incisor teeth while the role of the mylohyoid nerve in the mandibular posterior tooth sensation is still a controversial issue. Although variations in the course of the mylohyoid nerve in relation to the mandible are frequently found on the dissecting room, they have not been satisfactorily described in the anatomical or surgical literature. It is well known that variations on the branching pattern of the mandibular nerve frequently account for the failure to obtain adequate local anesthesia in routine oral and dental procedures and also for the unexpected injury to branches of the nerves during surgery. Also, anatomical variations might be responsible for unexpected and unexplained symptoms after a certain surgical procedure. We describe the presence of a communicating branch between the mylohyoid and lingual nerves in an adult male cadaver, and discuss its clinical/surgical implications as well as its possible role on the sensory innervation of the tongue. The present study reinforces the idea of a communicating branch between the mylohyoid and lingual nerves, indicating that some of the sensory components of the MHN, instead of innervating the teeth or chin skin, might also innervate the tongue and surgeons might be aware of this variation for the correct interpretation of the unexpected findings after oral nerves injury.