Mentolabial Sulcus, Anterior View

Description

Centered on the lower third of the male face, the mentolabial sulcus forms a transverse groove between the inferior vermilion border of the lower lip (labium inferius) and the mental prominence of the chin. Superiorly, the sulcus abuts the sublabial region just beneath the red lip margin; inferiorly it transitions onto the convexity of the mentum, approaching the pogonion at the most anterior midline point of the chin. Medially the crease is usually deepest, then softens laterally toward the labiomental folds, where the contour blends into the perioral soft tissues. Surgically and aesthetically, this is a high-stakes landmark because it reflects the relationship between the lower lip, mandibular symphysis, and the underlying mentalis muscle, and small changes in soft-tissue support can flatten or exaggerate the crease. Overactivity or hypertonicity of the mentalis produces the classic “cobblestoning” of the chin and an accentuated mentolabial fold, while aging and volume loss can deepen the sulcus even when occlusion is stable. It also guides planning for lower lip and chin procedures, including genioplasty, mentoplasty implants, and botulinum toxin injection patterns where diffusion can affect lower lip competence. Use this anterior view for head and neck anatomy teaching (surface anatomy of the face), orthodontic and maxillofacial surgery texts discussing lower facial profile, and cosmetic medicine materials addressing perioral aging, chin projection, and mentalis-related dynamic wrinkles. Anatomical accuracy verified by SciePro's Medical Advisory Board.