This study assesses the effects of superior repositioning of the maxilla by LeFort I osteotomy on adolescent maxillary growth. A total of 48 patients, 23 who were stabilized with rigid fixation (RF) and 25 stabilized with wire fixation (WF), were compared with closely matched unoperated controls. Comparisons were made for the presurgical intervals (2.3 years for RF and 1.3 years for WF groups) and postsurgical intervals (1.9 years for RF and 2.3 years for the WF groups). Lateral cephalograms were evaluated to describe the presurgical and postsurgical spatial changes of the maxilla. During the presurgical interval, there were no significant differences in vertical or horizontal maxillary growth between the WF group and their controls. Although vertical growth changes were similar, the RF group showed slightly more than expected posterior movement of the upper incisor during the presurgical interval. During surgery, the maxilla was advanced approximately 2 mm and impacted approximately 2 mm. After surgery, there were no statistically significant differences in vertical maxillary growth between the two surgical and control groups. Horizontally, the RF group showed maxillary stability, whereas the WF groups showed posterior movement. It is concluded that multiple piece LeFort I osteotomy has little or no effect on vertical maxillary growth; rigid fixation provides superior long-term anteroposterior stability compared with wire fixation.