The sagittal curving osteotomy: a modified technique for advancement genioplasty.

[PURPOSE] The purpose of the present study was to develop a new type of osteotomy for advancement genioplasty to decrease the incidence of neurosensory disturbance of the chin.

[PATIENTS AND METHOD] Forty-six patients who suffered from a slight or moderate degree of microgenia received a sagittal curving osteotomy for advancement genioplasty. Patients were followed for 1-6 months to assess the neurosensory function of the chin region by evaluating light-touch perception. The control group, 57 patients, who suffered from the same degree of microgenia, received a horizontal sliding osteotomy. They were operated on by the same surgical group and were followed for 1-33 months.

[RESULTS] All of the test and control patients were satisfied with the aesthetic results of the surgery. In the test group, 47 sides (51.87%) of 92 total left and right sides of chins had a transient neurosensory deficiency but none had permanent neurosensory deficiency. In the control group, 98 sides (86.84%) of 114 total chin sides had a transient neurosensory deficiency and five sides (4.43%) of 114 total chin sides had permanent neurosensory deficiency. When applied to patients who suffer from a mild or moderate degree of microgenia and have normal bite function, the sagittal curving osteotomy is a simple, safe and effective technique for advancement genioplasty. This technique can distinctively decrease the incidence of neurosensory disturbance of the chin.