Stability after inferior or anterior maxillary repositioning by Le Fort I osteotomy: a biplanar stereocephalometric study.

A biplanar cephalometric stereoradiographic system was used to measure maxillary positional changes during and after Le Fort I procedures for inferior or anterior repositioning of the maxilla. Of the 29 patients studied, 25 had undergone surgical maxillary advancement, and 15 had undergone inferior repositioning. These cases were divided into subgroups based on fixation technique, presence or absence of bone grafts, age, and surgeon. The postsurgical follow-up period was at least 11 months for each patient. The landmarks used to measure maxillary positional changes consisted of skeletal features and points on wire or rigid fixation devices. Mean magnitudes of postsurgical maxillary landmark displacement were insignificant for all subgroups examined except the advancement group with wire fixation. Individual patients exhibiting the greatest postsurgical displacements tended to have had large surgical advancements and received wire fixation. Magnitudes of surgical and postsurgical change did not seem correlated on the whole, except in the maxillary advancement cases in which bone grafts had not been used. Error analysis results suggest that digitizing consistency was acceptable for maxillary landmarks; however, methodologic improvements with regard to provision of cranial reference landmarks may further minimize errors in future studies.