Background: In female chin augmentation, whether it is done by implant or a bony advancement, consideration must be given to avoiding an aesthetic over correction. The traditional cephalometric measurements that indicate the ideal position of the chin does not really apply to most women. What matters aesthetically is not what the bone or soft tissue landmarks indicate but what the patient prefers. This is better determined by computer imaging of the patient’s pictures. (morphing different chin positions) Since chin augmentation is about numbers (millimeters of projection) a good guideline is whatever number is chosen don’t hesitate to back off 1 or 2mms. Many more women have sought revision for too much as opposed to too little.
When the chin augmentation is too much, and an implant was used, this is a relatively easy fix and there is only one option. But when it is done by a sliding genioplasty it poses more challenges and one has different options. A subtotal sliding genioplasty reversal is the obvious option but some patients may not want to go through the trauma of the intraoral approach and bone cutting again. The alternative is an external submental approach with bone burring and excision of any residual soft tissue chin pad. One consideration between these two options is how much reduction of the advancement is needed. For the sake of a few millimeters of setback redoing the osteotomy may seem ‘excessive’ and the submental approach involves less trauma and recovery.
One unique adverse event from a sliding geniopalsty advancement is the creation of hyperdynamic chin pad ptosis. This can occur for two main reasons. First a fleshy chin pad may have pre-existed and the advanced bone has pushed it forward making it more prone to being pulled down with smiling. Secondly excessive soft tissue degloving off of the front of the bone may have been done for the osteotomy and plate fixation and, if the advancement was only a moderate amount, the lack of soft tissue reattachment to the bone afterwards makes it prone to hyperdnamic and even non-dynamic chin pad ptosis. Chin pad ptosis can be treated by intraoral resuspension but that is not always reliable. A submental chin pad excision and tuck is the definitive treatment for any form of chin pad ptosis.
Case Study: This female had a prior 8mm sliding genioplasty advancement that she felt look too different for her. It also deepened her labiomental fold considerably. She also developed a hyper dynamic chin pad ptosis that did not exist previously. In effort to treat her chin pad ptosis she underwent a second procedure of intraoral plate removal and chin pad resuspension…which helped the chin pad ptosis a little bit but did not decrease the chin projection. She now came to me fror a submental approach to treat both the excessive chin projection and ptosis.
Preoperative marking made from the corner of the mouth inferiorly and meeting in a V in the neck provides a lateral limit to the extension of the incision.
Under general anesthesia through a submental incision the chin bone was exposed which showed a prominent tubercle. Using a reciprocating saw 3mms of horizontal projection was reduced by removing the tubercle and then tapering the sides so the chin did not look wider.
The chin pad was then brought down over the reduced chin and tucked and tightened to the inferior bony border. In so doing this creates a submental neck flap excess which is trimmed and removed.
The decrease in chin projection could be appreciated at the conclusion of the surgery. The assured iumprovement in the dynamic chin ptosis awaits the complete resolution of all swelling and the return of normal chin soft tissue movements. (6 to 8 weeks after the surgery)
Key Points
1) In females it is not uncommon to have an over advanced sliding genioplasty that the patient never can adjust to the new look.
2) A sliding genioplasty can cause hyperdynamic chin pad ptosis if it existed previously, excessive tissue stripping is done from the end of the bone and/or the chin has been rotated upward.
3) An over projected chin with hyperdynamic chin pad ptosis can be effectively treated with submental chin reduction techniques.
Dr. Barry Eppley
World-Renowned Plastic Surgeon