Long-term skeletal stability after rigid fixation of Le Fort I osteotomies with advancements.

The purpose of this retrospective study was to evaluate relapse, comparing large and small maxillary advancements with four-plate rigid fixation and without bone grafting. All patients had obstructive sleep apnea, and underwent bimaxillary surgery. Standardized cephalometric analysis by two separate examiners was performed on serial radiographs of 20 patients immediately before surgery, and at 1 week and at least 6 months postoperatively (mean 18.5 months). The group was divided into three subsets to determine whether the magnitude of maxillary advancement correlated with the magnitude of relapse. In group 1 (< or = 6 mm, n = 4), the average advancement was 4.7 +/- 0.8 mm, with a mean relapse of 0 +/- 0.6 mm. In group 2 (7-9 mm, n = 9), the average advancement was 8.2 mm +/- 0.9, with a mean relapse of 0.7 +/- 1.5 mm. In group 3 (> or = 10 mm, n = 7), the mean advancement was 12.3 +/- 2.8 mm, with a mean relapse of 1.9 +/- 1.8 mm. There was no statistical difference in the measured relapse among the groups.