Background: While the custom jawline implant has the most powerful effect at changing the shape of the lower face the implant design alone does not necessarily indicate its outward effects. There is always the significant influence of the thickness of the overlying soft tissues particularly in the jaw angle area. The patient that gets the most definition from their custom jawline implant usually has a thinner soft tissue cover. Thicker tissue patients often achieve less than their desire definition as the overlying soft tissue has a blunting effect on the implant design.
While the thickness of the overlying soft tissues has an effect on the implant design prominence the other soft tissue issue is laxity or looseness. This potential soft tissue issue is obviously more of a concern in the older patient who has the onset of facial aging as well as the patient who may have lost a large amount of weight. As a result the older patient poses some different considerations then that of the younger patient in custom jawline implant designs.
Interestingly there are different in opposite soft tissue considerations between that of the chin and the drawl angles in custom jawline implant designs. In the chin it is more of a restriction issue. The soft tissue chin pad is tightly adherent to the bone and as a result they are limitations as to how much forward and vertical chin elongation can be done. In the jaw angle area, however they is a different type of soft tissue restrictions. While the skin can stretch almost limitlessly the underlying masseter muscle is what poses stretch limitations from the effects of jaw implant expansion. There is not an exact mathematical formula that can tell one what the soft tissue restrictions are in the chin and jaw angle area. This relies on a lot of clinical experience to develop a feel for each individual patient’s implant design.
Case Study: This middle aged male desired and improved jaw/lower facial appearance. He did have a history of a prior chin implant but this proved to be inadequate for him. His 3D CT scan showed a style one square chin implant with 5 mm of horizontal projection that was well-placed. But clinical evaluation of his face demonstrated that his more significant dimensional need was vertical with that of a short lower third of his face. Therefore in the chin area he would be better served by a combined horizontal and vertical lengthening implant design or any more 45° type of chin dimensional change. His jaw angles showed a very typical bony shape that did not appear to be I hatevertically short unlike his chin. But his external facial appearance showed a vertically short lower face. His soft tissues showed laxity and thicker skin which was consistent with a middle-age male.
Using this information a custom jawline implant was designed to provide a significant wraparound augmentation affect but also a design that did not exceed what his soft tissue restrictions were. In vertical chin lengthening the design is done to try and ensure that the soft tissue chin pad will wrap around the end of the implant as well as to try to limit the risk of masseteric muscle dehiscence back at the jaw angles. The implant design also took into consideration the horizontal projection provided by his existing chin implant with some additional projection to it. He also had custom midface implant replacements but that is what are you doing move up and see your brothersnot part of this discussion.
Under general anesthesia and through a three incisional approach his existing chin implant was removed through the submental skin incision. (which already existed) in comparing they remove chin implant to the custom jawline implant the significant difference in their potential effects could be seen. Combined with posterior intraoral incisions the custom jawline implant was inserted and the chin portion of it was initially secured with double screw fix station. This is a key maneuver in custom jawline implant placements as the accurate placement of the chin portion of the implant will influence the accuracy of the placement of the rest of the implant behind it. Once the chin portion of the implant is set then the jaw angle portions through the posterior incisions can be positioned and secured with screws. A bit like laying carpet when one corner of the implant is set (chin) then the other two corners can be properly stretched out and positioned.
When seen six months later at the time of his stage 2 facelift the improvement in the size and shape of his lower jaw could be seen. It should also be noted that while this was a significant improvement there is not any sharp definition in the jaw angle area as would be expected with his age and thicker soft tissues. There was, however, noticeable improvement in the length of the lower third of his face. I got into Brian
Custom jawline implants offer improved jaw size and shape. But not every jawline implant design is going to get the same result. Different effects will occur based on the bony anatomy and the overlying soft tissues. The older patient, older as defined by not younger (under the age of 35 years old), will have additional issues of soft tissues laxity and facial fat accumulations that the younger patient may not have. How this may factor into the implant design must be considered on an individual patient basis….meaning is a bigger implant design appropriate or is soft tissue reductions also needed at the same time as implant placement or done as a second stage procedure.
Key Points:
1) About 1/3 of all custom jawline implant patients are those who have had a prior chin implant surgery
2) Many unsuccessful chin implant results are those placed in patients in which the complete three dimensional needs of the chin augmentation is not recognized.
3) How much definition that can be achieved with a custom jawline implant is partially dependent on the thickness of the overlying soft tissues.
4) When the chin is vertically lengthened as part of a custom jawline implant an existing vertical chin pad cleft becomes more superiorly located. (the chin cleft became more of a chin dimple)
Dr. Barry Eppley
World-Renowned Plastic Surgeon