Modified technique of chin augmentation with MEDPOR for Asian patients

Commonly used chin implants are made of silicone, expanded polytetrafluoroethylene (e-PTFE), or high-density porous polyethylene (MEDPOR). Although MEDPOR is an effective implant for chin augmentation, modification of the external aspect of the implant is recommended, particularly for Asian patients, to create an appropriate shape for the new chin. It is often difficult to contour the inner aspect of the implant to conform to the patient's mandible. Without modification, a gap may exist between the implant and mandible. To address this problem, a modified augmentation technique was developed.

The authors describe their modified technique for MEDPOR chin augmentation, which includes removal of the genial tubercles and, if necessary, the mental protuberance.

Ninety-five patients underwent the modified MEDPOR technique of chin augmentation. Before placement of the contoured implant, a drill was used to remove the patient's genial tubercles. If the mental protuberance was deemed too prominent, it was removed as well. The implant was inserted and fixed to the mandible with 2 titanium screws.

Results were satisfactory in 90 cases. Chin shape was too "strong" in 4 patients, and another patient had poor transition between the implant and mandible. Complications were minimal. The most common complication in this modified technique was lower lip numbness, which was transient in all cases.

The MEDPOR chin implant can be effectively contoured to the mandible by removing the genial tubercle and/or mental protuberance. This technique is less invasive than chin osteotomy. Successful results can be achieved with minimal risks.