Changes of the profile after advancement genioplasty.

Surgical advancement of the chin, and postoperative relapse, were studied during a three-year period in 17 patients. Changes were measured on lateral cephalograms obtained at certain intervals. Sagittal skeletal changes were recorded parallel to the Frankfort Horizontal plane. Soft tissue changes were recorded by advancement of soft tissue Pogonion along a line parallel to the mandibular base line and by the increase of the angle NFL/NCL. The average skeletal advancement was 8 mm with a relapse of 1 mm two months after surgery. No further changes were registered during a three-year observation period. The average soft tissue advancement was 7.5 mm from two months after surgery and no relapse was found after this time. The soft to hard tissue ratio of the changes was 0.94 which corresponds to results reported in the literature. There was no correlation between the average amount of advancement and the amount of relapse. The range of changes showed a wide variation, however.