Cutaneous sensory branch of the mylohyoid nerve.

The study is aimed at the anatomical detail of the cutaneous sensory branch of the mylohyoid nerve (MHN), which is distributed to the chin, as it relates to submental surgery. Dissection was done on the both sides (16) of eight cadavers fixed in formaldehyde solution. A distance from gonion of the branch innervating the anterior digastric and mylohyoid muscle and the cutaneous sensory branch was measured. The cutaneous sensory nerve was 27.0+/-8.6 mm long and numbered 2.3 (14.4%) of 16 specimens. The area distributed by most branches (78%) was a rhombus, having all four sides equal (15 mm), extending to the mental prominence and submentum. The divergent angle of the two facing sides of the bilateral rhombi was 60 degrees. Informed surgical manipulation of the mental area may avoid unnecessary damage to the sensory nerve.