Neuroanastomosis and the innervation territory of the mental nerve.

The aim of this study was to clarify the distribution pattern and innervation territory of the mental nerve (MN) in the skin and mucosa by topographic examination by Sihler's staining, thereby providing reference anatomical information for surgical procedures and to enable prediction of regions of sensory disturbance following nerve damage. Ten human specimens were subjected to Sihler's staining, which is a highly accurate method for visualizing the distribution of nerve fibers without altering their topography. Each branch of the MN overlapped adjacent branches (five cases), or else they were distributed individually at the lower lip (five cases). The MN anastomosed with some branches of the facial nerve near the mental foramen. Moreover, some branches of the MN anastomosed with the buccal nerve of the trigeminal nerve, which supplies sensation to the skin and mucosa over the lateral region of the lower lip (six cases). The details of the distribution pattern and innervations territory of the MN presented herein may enable the prediction of a region of sensory disturbance following MN damage. Moreover, knowledge of the pattern of synapses with adjacent branches of other nerves, such as the facial (marginal mandibular and cervical branches) and the buccal nerves, might help to improve our understanding around incomplete anesthesia during the surgical procedures in oral & maxillofacial region.