Background: Chin implants are a common facial augmentation that can be very effective for the properly selected patient. They work best for modest to moderate chin deficiencies that are largely horizontal in dimension (inadequate projection) with no significant asymmetries in the chin or jawline bone. Where patients and surgeons get into aesthetic difficulties is when a multidimensional deficiency and/or asymmetry exists in the chin. Then the use of a standard implant is being asked to fulfill an aesthetic outcome for which it was not designed.
While it is true that chin implants can be intraoperatively modified to try and compensate for a patient’s asymmetries or placed in various position on the bone to create a patient-specific need, they are now being asked to fulfill an aesthetic goal for which they were not designed. In some cases this may produce a satisfactory outcome but far too often it does not. This may then lead to another surgery or even a series of surgeries to try and ‘get it right’.
Recognizing the need to go to a custom implant design from the beginning is the obvious best approach in chin augmentation. In my experience the majority of custom chin implants are done as secondary or tertiary procedures after standard implant efforts. But the key indicator for a custom design as a primary chin implant augmentation procedure is the presence of asymmetry, particularly if there is a more global jaw asymmetry.
Case Study: This male had a prior history of double jaw surgery. There was left-sided jaw asymmetry prior to that surgery and it remained so afterwards. His chin augmentation goal was three fold: 1) correct the chin asymmetry, 2) create horizontal and vertical augmentation and 3) male a more square-shaped chin.
A custom chin implant was designed to achieve all of these chin augmentation effects. This required that a longer extension back along the jawline was needed on the left side which interfaced with a large reconstruction plate used in the prior surgery.
Under general anesthesia and through a submental incision the custom chin implant was placed and secured with a central screw fixation. A buccal liecptomy was also performed at the same time.
When seen two years later his lower facial reshaping and custom chin implant augmentation effects showed the improvement.
Of particular interest was the correction of his chin asymmetry and a less round chin shape.
This patient recognized the need from the beginning of a custom implant design for his chin augmentation. Any one of his three chin reshaping objectives was best served by a custom implant design. But all three together made it essential.
Key Points:
1) In chin asymmetries, whether it is horizontal or vertical in dimension, the use of standard chin implants inadequately addressed the asymmetry and often just creates another version of it.
2) A custom implant design for chin asymmetries provides the best opportunity to successfully improve the chin’s projection and shape.
3) Chin bone asymmetries create very asymmetric implant designs which need to be factored into their placement.
Dr. Barry Eppley
World-Renowned Plastic Surgeon