Background: A custom jawline implant provides the greatest contour change possible to the lower third of the face. That is not surprising due to its sheer size and surface area coverage of the mandible. The design process is impressive and empowering as it is possible to design about any size and dimensions that the patient wants.
But there are two major challenges in the custom jawline implant design process. First, determining what design will create the desired external facial change is not an exact science. No computer design software yet exists that can tell us what that design should be. Currently the design still requires all dimensional input from the surgeon which is based ion their personal experience. But of almost equal importance is can the implant as designed actually be placed and how is that exactly done.
To place a custom jawline implant as designed as a single piece, a ‘front to back’ technique is needed. The most narrow part of the subperiosteal pocket along the jawline is right below the mental nerves. To get the implant underneath the mental nerves safely, the more vertical jaw angle parts of the implant must be become ‘moldable’.
Case Study: This young male desired a stronger jawline with a prior history of an inadequate chin implant and significant jaw angle asymmetry. A non-linear jawline implants was designed with prominent chin corners and jaw angle flare.
As part of the implant design to make the jaw angles foldable, internal 10 degree wedges of material were removed from the inner aspect of the jaw angles. This would allow them to be folded and passed under the most narrow part of the pocket beneath the mental nerves.
Under general anesthesia and using three cm long incisions (one external submental and two intraoral mucosal), a complete subperiosteal pocket was created. The implant was introduced from side to side by folding and clamping he jaw angles of the implants onto themselves and the passing the under the mental nerve. The jaw angels were released and unfold on their own which then allowed the three corners of the implant (chin and bilateral jaw angles) to be positioned and secured by screws.
The design of a custom jawline implant must take into consideration more than its shape and dimensions for the desired external facial effect. Its design must consider how it can be placed through minimal incisions as well as properly oriented on the bone as designed.
Case Highlights:
1) Custom jawline implants due to their size and the need for small incisions create the greatest challenges for intraoperative placement.
2) Placing the implant in one piece as designed requires maneuvering the jaw angles portion under the mental nerves without injuring them.
3) In a front to back placement technique, malleability of the large jaw angle portion of the implant is the key.
Dr. Barry Eppley
Indianapolis, Indiana