Background: The labiomental sulcus, often referred to as the labiomental fold, is the natural indentation at the upper extent of the soft tissue chin pad below the lower lip. Its depth varies based on genetics and bony chin shape. It represents the bony origin of the mentalis muscle attachment and the depth of the intraoral vestibule. The aesthetics of the sulcus depth can be debated but its general morphology should be that of a subtle curved concavity.
The depth and shape of the labiomental sulcus can be affected by various types of aesthetic chin surgery. Chin augmentation, whether done by an implant or a siding genioplasty, will almost always make the sulcus deeper. How much deeper depends on the amount of chin augmentation and the natural depth of the presurgical sulcus.
A chin implant makes the labiomental sulcus deeper by pushing out the soft tissue chin pad beneath it. A sliding genioplasty makes it deeper by pushing the bone out beneath it…and also creating a bony shelf or step off in the shape of the bone beneath it. That is a unique bony shape alteration that can lend itself to a significant deepening effect from scar contracture.
Case Study: This male had a prior history of orthognathic surgery which involved a sliding genioplasty. The amount of forward movement of the chin was unknown. It was fixed by plate and screws centrally and wires laterally. He developed afterwards a severe labiomental sulcus contracture with a v-shaped indentation. His lower lip remained tight and was numb and the chin appeared vertically short. This represented more than just a natural deepening of the labiomental sulcus but an actual scar contracture into the bony step off of the sliding genioplasty.
Given the deep v-shape of the labiomental sulcus and the tight lower lip, an intraoral release and the placement of an interpositional dermal fat graft as chosen. A 5cm long dermal fat graft was harvested from his right flank and the labiomental sulcus widely released through the original intraoral incision.
The dermal fat graft was positioned into the chin soft tissue defect by a percutaneous sutures technique. A two layer deep closure and an overlying mucosal closure was then done.
His immediate results showed the unfurling effect of the soft tissue chin pad and resultant vertical chin lengthening. The depth of the labiomental sulcus was appreciably softened.
There is a big difference between a labiomental sulcus that naturally gets a bit deeper because of movement of the soft tissue pad beneath it vs the labiomental sulcus that gets pulled into the bony step off of a sliding genioplasty. The latter represents a true scar contracture deformity and requires a traditonal approach to any type of scar contracture deformity….release and the placement of something to prevent its recurrence. While fat injections may work for the subtle and rolling concavity of a deeper labiomental sulcus, that approach will rarely work for a fixed scar contracture. This determination can be made non-surgically through injections of saline or filler materials. If the labiomental sulcus comes out with any type of injection then fat injections will be successful. If not then a formal release and en bloc soft tissue graft is needed.
Case Highlights:
1) Labiomental sulcus contracture after a sliding genioplasty causes a v-shaped deformity, tight lower lip and a vertical shortening of the chin height.
2) Labiomental sulcus contracture is treated by release and an interpositional soft tissue graft if it fails the injection test.
3) A autologous dermal fat graft is a good interpositional material to provide a sustained labiomental sulcus release and unfurling of the soft tissue chin pad.
Dr. Barry Eppley
Indianapolis, Indiana