Background: Chin implants are the most common form of facial augmentation and have the largest selection of styles and sizes of any facial implant. But despite this wide selection there are some patients in which a standard chin implant will not suffice. This is particularly relevant when any degree of vertical lengthening is needed or a very specific chin hape is needed. (e.g., square shape)
A custom chin implant offers the ability to make any desired dimensions and shape the patient desires as long as it does not exceed the coverage capacity of the overlying soft tissue. The critical question is what should those exact implant dimensions be made to achieve the look that the patient desires? The computer can make what it is told…but it has to be told what to make. No software program can make a design knowing the exact patient external look it will create.
Until there is computer software that can transfer any custom implant design to what it will actually like on the patient’s external appearance, the best that can be done is to ‘guess’ as to what the effect will be. Experience helps in this guessing but there remains currently no precise translation of implant design to the external change in facial appearance.
Case Study: This young male desired a chin shape change that, while not large, had very specific dimensional changes. He did his own computer imaging of his pictures and had them blown up to life size pictures. I then cut out his face on the pictures and overlaid tea on paper and traced out the before and after outlines on both the front and side views.
From these tracings the exact chin dimensions and shape are determined. Such measurements were transferred to the implant design process to come up with the custom chin implant design.
Under general anesthesia and through a submental skin incision the custom chin implant was placed in a suboeriosteal designed pocket. The implant was centered and secured with two screws.
The custom facial implant design process has no exact method to know what the correlation between the implant design and the change in desired external facial appearance. This ‘old school’ method of pictures and hand drawings still works well for edge structures like the chin in determine the exact implant dimensions needed.
Highlights:
1) A custom chin implant is needed when standard chin implants can not achieve the dimensions needed, particularly that of vertical lengthening.
2) One method of creating the desired chin shape change is to take measurements from life size before and after morphed pictures.
3) The computer design process for the custom implant then uses the measurements of the cut out chin implant morph from the pictures.
Dr. Barry Eppley
Indianapolis, Indiana