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Dr. Yaremchuk:
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chin implants
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Chin implant surgery has long been touted as a simple operation that reliably gives good results. Dr. Yaremchuk belives that the aesthetic result is often less than ideal when conventional techniques are used. The result may be compromised by the preoperative analysis, the surgical technique, the implant design and the host response to the implant material.
The adequacy of chin projection should take into account several variables including sex, the effect of occlusion on lower lip position, the thickness of the chin pad, and the depth of the labiomental fold. When these variables are not considered, implant augmentation may result in a chin that is unnatural and too large, particularly in a woman.
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This diagram is adapted from the work of Farkas and his coworkers. It shows the average profile of a young North American Caucasian female. The chin point lies an average of 4.1 degrees behind a perpendicular dropped from the glabella (lower forehead). At 1 standard deviation (SD) (the area colored in orange) the chin point still lies behind the perpendicular line (dashed line) dropped from the forehead.
The diagram adjacent to it shows the average profile of a young North American Caucasian male. It documents that men have more prominet chins than women do. However, only at 1SD does the chin point met the perpendicular (dashed line) dropped from the forehead. These meaasurements show the differences between women's amd men's faces and help explain why impants that are too large may be interpreted as unnatural and may masculinize a woman's face.
Chin augmentation with certain shaped implants can create unnatural chin contour. Implants that augment only the chin point produce an abrupt , protruding chin rather than a jaw-chin continuum.
This patient shows how a large implant that augments the chin point only can create an unnatural 'stuck on' appearance.
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Extended one piece implants do not always match the contour of the native mandible. Particualrly when placed through small intraoral incisions, minimal inaccuracies in placement or asymmetries in the native mandible, may result in gross distortions and irregularities lateral to the chin point.
The diagram shows how this may happen. The clinical example shows the resultant distortion in mandibular contour.
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Dr. Yaremchuk has designed a two piece implant which helps to avoid some of these problems. Patients who have had surgery with his implant are shown in the patient example section of this website.
Illustration by Kip Carter, MS, CMI
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