Stability after maxillary segmentation for correction of anterior open bite: a cohort study of 33 cases.

The aim of this cohort study was to evaluate the stability after multi-segmentation of the maxilla for correction of anterior open bite deformities. A total of 33 patients who underwent segmented maxillary osteotomy between 1994 and 2006 were included in the study. Rigid fixation with plates and postsurgical intermaxillary fixation for 6 weeks was applied to each patient. All patients were then followed in a standardized examination procedure at months 6, 12, 18 and up to 30 months postoperatively. Vertical and horizontal relation of the incisors was measured both clinically and on cast models. The main finding was that statistically significant relapse was found vertically, whereas the horizontal relationship to the mandible was unchanged. The vertical relapses were predominantly seen in patients with severe open bite evident preoperatively.