The custom jawline implant provides the most significant aesthetic change to the lower third of the face. This is due to its ability to affect all three dimensions of the jawline as it wraps around it. While there are various factors that affect the aesthetic outcome in the placement of a custom jawline implant, tissue thickness being a major one, the implant design certainly makes a major contribution to the end result.
There is no textbook or manual for how to design a jawline implant. It takes experience in doing it with a prerequisite of having placed a lot of standard chin and jaw angle implants of various shapes and sizes to come to appreciate their effects as well as the nuances of their placement. But the most significant learning curves comes from designing and placing jawline implants over a long period of time.
Having done numerous jawline implant replacements which were designed by other surgeons there are some great examples of how jawline implants should NOT be designed. Since most men are seeking almost the same aesthetic effects, a more angular and well defined lower jaw regardless of size, there are some basic design guidelines to be followed.
First and foremost the implant design should be angular in appearance as it appears on the bone or the implant design file. The shape of the chin and jaw angles should rarely be rounded if an angular result is the goal. Rounded designs like this one are not usually what most patients want. (green color) The overlying soft tissues will blunt many of the affects of an implant’s design, particularly in medium to thick-skinned patients. So the result will only be a fuller/wider jawline but not one with any definition.With a few angular design changes a much better implant design can be created. (teal color)
One of the main benefits of a custom jawline implant is its connectivity between the chin and the jaw angles. Implant designs that merely follow the natural slope or S-shape of the inferior border of the lower jaw works against creating this desired effect. (green color) To create a linear design the jaw angles need to be lowered to create a straight line between the chin and jaw angles.(teal color) How much the jaw angles need to be lengthened depends on how high the jaw angles naturally are. This also has the effect of making the jaw angle part of the implant more visible.
A more square chin and jaw angle requires fairly sharp corners. While not every male wants a square chin look, most do not want a rounder one either. (green color) The principle of the soft tissues blunting the effects of the implant design comes into play particularly in the chin where even a square design does not necessarily make it look too square or wide. One has to be more careful about square designs in the jaw angle area because the masseter muscle may not always cover it depending upon how much vertical lengthening, if any, is being done.
For the jaw angle areas a convex shape in the frontal view is to be avoided. With the thickest part of the masseter muscle being above the inferior border, a convex jaw angle shape will merely push out the muscle thickness making the jaw angle fuller/thicker but not defined. The widest part of the jaw angle design should be at the lowest part of the implant with a concave shape, limiting how much the thickest part of the muscle is widened.
While these design guidelines are not a complete list of all the nuances of a custom jawline implant design, they are some of the major ones that I commonly see in inadequate designs.
Dr. Barry Eppley