The chin represents one of the five main prominences of the face, also including the nose, brow ridges/forehead, cheeks, and jaw angle. It is the defining feature of the lower face. Augmentation or enhancement of a recessed or weak chin is a common plastic surgery procedure that is made fairly simple through the placement of a synthetic implant. Correction of a large or too prominent of a chin, however, is not only less commonly done but is more difficult to do successfully.
A prominent chin has both excess hard and soft tissue. This means that the bone not only has to be reduced but the muscle and skin must be shortened and tightened as well. If the soft tissue of the chin is not properly addressed in a reduction, it will sag off of the reduced bone after surgery resulting in what is known as a ‘witch’s chin’ deformity.
Chin implant surgery is traditionally done through an incision under the chin in the submental crease. But in a chin reduction procedure, this incision should be moved back a bit accounting for the removal of some submental skin at the end of the procedure. Once the chin bone is exposed, the excess chin is burred down the amount estimated beforehand. Usually it takes at least 6 to 8mms to make a significant difference. It is important to make sure that the bone removed extends far enough to the sides and is tapered to keep the chin from being too square. Once the bone is removed, excess mentalis muscle is removed and this muscle flap is sutured to the underside of the chin to the platysma muscle. Making this a tight muscle closure is important. Redundant overlying submental skin is then removed and closed as well. The soft tissue closure is just as important as the bone removal.
This approach works well for a horizontal chin excess. A vertical chin excess or a long chin, however, requires an intraoral approach with an interpositional wedge osteotomy for its correction. This is a completely different operation with removal and repositioning of bone rather than a simple burring down technique.
Dr. Barry Eppley
Indianapolis, Indiana