Background: In aesthetic jaw augmentation the most common approaches are purely implant-based. Using either standard chin and jaw angle implants or a custom wraparound implant the entire jawline can be augmented. The only autologous jaw augmentation method is for the chin with a sliding genioplasty. So another complete jaw augmentation method is to combine a sliding genioplasty with jaw angle implants. Although this is the last common method used presumably because it does not add width to the chin or body of the mandible.
A similar but more versatile combination of a bony genioplasty and implants is to use a custom jawline implant as opposed to standard jaw angle implants. This provides an assured coverage of the posterior step offs from the genioplasty wings and well as a smooth jawline border from one side to the other. In essence think of it has a bony change of the lower jaw inside the confines of a custom jawline implant. As a result it lessens the amount of implant load over the solitary projection of the chin.
The key indication for this unique use of a custom jawline implant is when the chin needs significant vertical or horizontal projection increase. The soft tissue chin pad, which is a naturally tightly adherent drape over the chin, has limitations of how much it can be safely stretched over an avascular implant. There are no such restrictions with a bony genioplasty as the soft tissue pad goes where the bone goes as its inferior attachments are undisturbed,
Case Study: This older male desired a complete lower jaw augmentation for a vertically short chin which he had his entire life. Twenty years previously he had a vertical lengthening chin procedure with a bone graft and wire fixation. A 3D CT scan showed four vertical loops of wire. Whatever amount of chin lengthening that was achieved it had created more of a mandibular plane angle with the presence of a prominent antegonial notch. But even so his lower facial third remains short.
A comprehensive jaw augmentation method was planned with a combination horizontal and vertical bony genioplasty (12mm forward and 5mms vertical lengthening) with a custom jawline implant. The implant design vertically lengthened the jawline behind the chin as well as
Under general anesthesia and through an intraoral incision the chin was exposed, the four wires seen and removed. The chin was then cut and moved 12mms forward and 5mms vertically using a bent 14mm chin plate and two side stabilizing plates. The custom jawline implant was inserted through posterior intraoral incisions after being split in half. It was reunited over the front end of the advanced chin and secured with screws to it.
Getting the thin front end of the jawline implant around the advanced genioplasty without riding up into the osteotomy cuts is always a challenge. But very important to do so to prevent a disruption of the jawline by exposed the back end of the osteotomy cuts.
While relatively unknown the combination bony genioplasty and custom jawline implant is the most powerful jaw augmentation procedure available. It goes beyond the limits of an implant in the chin by autologous movement and then combines it with whatever implant augmentation is desired behind it. In essence it captures the best of what the sliding genioplasty and custom implant designs can accomplish. It is technically challenging to perform even though it looks like an easy puzzle to put together on the implant design file. The hardest part is getting the wrap implant over the chin with the sides being down along the stepoffs of the osteotomy cuts…exactly where the intaoral visibility is limited.
1) A bony genioplasty combined with a custom jawline implant provides the best autologous and alloplastic jaw augmentation method.
2) The primary indication for this jaw augmentation method is the need for significant vertical chin lengthening.
3) It is best to make the custom jawline implant wrap completely around the advanced chin rather than having it stop along the sides of the osteotomy.
Dr. Barry Eppley
World-Renowned Plastic Surgeon