ORTHOGNATHIC SURGERY EFFECTS ON MAXILLARY GROWTH IN PATIENTS WITH VERTICAL MAXILLARY EXCESS

This study assesses the effects of superior repositioning of the maxil la by LeFort I osteotomy on adolescent maxillary growth. A total of 48 patients, 23 who were stabilized with rigid fixation (RF) and 25 stab ilized with wire fixation (WF), were compared with closely matched uno perated controls. Comparisons were made for the presurgical intervals (2.3 years for RF and 1.3 years for WF groups) and postsurgical interv als (1.9 years for RF and 2.3 years for the WF groups). Lateral cephal ograms were evaluated to describe the presurgical and postsurgical spa tial changes of the maxilla. During the presurgical interval, there we re no significant differences in vertical or horizontal maxillary grow th between the WF group and their controls. Although vertical growth c hanges were similar, the RF group showed slightly more than expected p osterior movement of the upper incisor during the presurgical interval . During surgery, the maxilla was advanced approximately 2 mm and impa cted approximately 2 mm. After surgery, there were no statistically si gnificant differences in vertical maxillary growth between the two sur gical and control groups. Horizontally, the RF group showed maxillary stability, whereas the WF groups showed posterior movement. It is conc luded that multiple piece LeFort I osteotomy has little or no effect o n vertical maxillary growth; rigid fixation provides superior long-ter m anteroposterior stability compared with wire fixation.