Comparison of symmetry of rapid maxillary expansion using a tooth-borne or a bone-borne distractor

Abstract

Background: There are differences in the distraction pattern of tooth-borne versus bone-borne rapid maxillary expansion. However, patients suffer especially from visible asymmetric distraction of the two maxillary segments. These have not yet been described. Objectives: We investigate the asymmetry in distraction of the two maxillary segments before and after expansion. Methods: We measured dental landmarks on 21 study casts preoperatively and directly after expansion with tooth-borne or bone-borne rapid maxillary distraction. The three-dimensional differences in distraction between the two maxillary segments were calculated. Findings: In this study group, there was no significant difference in the symmetry/asymmetry of rapid maxillary expansion using a tooth-borne the two maxillary segments seem to have another cause i.e. the operation technique than the device used for distraction. The study group is continuously increased to gain further results.