Mentalis Muscle

Description

Shown in lateral profile, the male mandible and overlying soft tissues frame the mentalis as a compact, vertically oriented muscle belly in the midline chin. Its fibers arise from the incisive fossa of the anterior mandible inferior to the incisor roots, then course inferiorly and slightly anteriorly to insert into the dermis of the mental skin, deep to the labiomental fold. Superiorly it blends with the inferior margin of orbicularis oris at the lower lip, while laterally it borders depressor labii inferioris and sits superficial to the mandibular symphysis. Bony context extends posteriorly to the temporomandibular joint, with the cervical vertebrae and sternocleidomastoid marking the upper neck. Small muscle, big surface effect. Functionally, the mentalis elevates and protrudes the lower lip and wrinkles the chin skin, so it is a primary driver of the labiomental crease and the classic chin dimpling seen with perioral effort. This side view matters when teaching or planning procedures for lower lip incompetence and “orange peel” chin, where overactivity or asymmetry is often treated with targeted chemodenervation, and where misplacement can produce an unflattering chin ptosis or altered smile dynamics. The close relationship to the anterior mandible also makes it a landmark in submental and lower facelift planning, where undermining in the wrong plane can denervate or detach the muscle’s dermal insertion. Facial anatomy and head and neck surgery courses can use this artwork to orient students to the soft tissue layers over the mandibular symphysis while keeping adjacent landmarks such as the TMJ, dentition, and upper cervical spine in view. It also fits well in dermatology, aesthetic medicine, and maxillofacial texts discussing the labiomental fold, chin contouring, and injection mapping for the perioral region. Anatomical accuracy verified by SciePro's Medical Advisory Board.