Mentolabial Sulcus, Anterior View

Description

Centered on the lower third of the face, the mentolabial sulcus (labiomental fold) is marked between the inferior margin of the lower lip and the superior contour of the chin. Superiorly, the labial region includes the lower lip vermilion and labiomental transition; inferiorly, the mental region includes the mental protuberance over the mandibular symphysis, with pogonion at the most anterior midline point. A thin line highlights the sulcus as it arcs transversely, remaining symmetric about the facial midline and sitting inferior to the oral commissures. Surface form here tracks underlying anatomy: contraction and tone of the mentalis, balanced by the depressor labii inferioris and depressor anguli oris, shape the depth of the fold and the projection of the soft tissue chin over the mandible. Small changes matter. In aesthetic medicine, overfilling the sulcus or misplacing neuromodulator can flatten the fold and create a “witch’s chin” appearance from mentalis imbalance, while in orthognathic planning and genioplasty the sulcus helps communicate mandibular advancement or setback and whether the lower incisor-lip relationship will read as competent or strained. The crease is also a reliable external reference when teaching the relationship between the mandibular symphysis, chin pad thickness, and lower facial height in standardized facial analysis across different skin tones. Use this anterior close-up in head and neck anatomy teaching to anchor facial topography terminology, in dentistry and orthodontics lectures discussing lower facial profile, or in aesthetic injection training materials that need a clear landmark for the labiomental crease and mentalis zone. It also fits clinical handouts and surgical consult documents where preoperative and postoperative soft tissue contour of the chin must be described consistently. Anatomical accuracy verified by SciePro's Medical Advisory Board.