Chin reduction poses challenges that other facial bone reductions don’t. Because it is a projecting structure with a tight soft tissue pad attachment, consideration must be given to what will happen to the ‘extra’ soft tissue once the bone is reduced. In addition the chin reduction technique used can also have an influence on the adaptation of the soft tissue to the bone…which ultimately affects its aesthetic appearance.
One type of chin reduction is that of vertical shortening. For the long chin it can be vertically reduced by one of two methods. One technique is the intraoral removal of a central horizontal wedge of bone using double osteotomy cuts. The bone segment is then removed and lower chin bone, which is still attached to the soft tissue chin pad, is ‘colllapsed’ upward or vertically shortened with plate and screw fiaxtion. By keeping the bone and the soft tissue connected, the risk of postoperative pad sag or ptosis is eliminated.
The other vertical chin reduction method is using a submental technique. From an inferior skin incision the soft tissue chin pad is elevated off of the bone which provide exposure for a lower border ostectomy. Depending upon how much bone is removed, there may be a need for soft tissue removal to level out the anterior chin soft tissue ad with that of the posterior neck tissue. While some patients may fear the submental incision, one of the key elements of this technique is that the length of the skin incision must be limited.
The advantages of the submental chin reduction technique are numerous, It avoids any risk of tooth root or mental nerve injury as well as eliminates the need of plate and screw fixation. Coming from below it also allows for greater bone reduction and a more direct or linear approach to further adjustment back along the inferior border for chin width reduction as well. Lastly, for the patient with a large soft tissue chin pad that is recognized preoperatively the submental approach provides an opportunity yo reduce it as well.
Dr. Barry Eppley