Skeletal stability of Le Fort I osteotomy in patients with unilateral cleft lip and palate

The skeletal stability of Le Fort I osteotomy was evaluated cephalometrical ly in 40 consecutive patients with unilateral cleft lip and palate (UCLP) ( 27 male and 13 female) who were operated on between 1987-1995. Their mean a ge at the time of operation was 23.7 years (range 16.3-40.4). The one-piece Le Fort I osteotomy was fixed with titanium plates and the osteotomy line was bone-grafted. Neither intermaxillary fixation nor occlusal splints were used postoperatively. Skeletal stability was analysed both horizontally an d vertically on cephalograms taken shortly before operation, immediately af terwards, and at six months and at one year postoperatively. The mean maxil lary advancement (point A) during the Le Fort I was 3.9 mm (range 0-8.9) an d mean vertical lengthening 4.5 mm (range -0.6-10.5). One year postoperativ ely the mean maxillary horizontal relapse was 20.5% (0.8 mm, range 0-3.7) w hereas the mean vertical relapse was 22.2% (1 mm, range 0-5.7). The vertica l relapse reduced from 38% to 8.3% between 1987 and 1995, and there was a p ositive, correlation between the amount of maxillary advancement and relaps e both horizontally and vertically.