Three-dimensional bimetric maxillary distalization arches compared with a modified Begg intraoral distalization system.

The purpose of this study was to compare the dentofacial effects of two intraoral molar distalization techniques [three-dimensional bimetric maxillary distalization arches (3D-BMDA) and a modified Begg intraoral distalization system (MBIDS)] in subjects requiring maxillary molar distalization. Twenty-one patients (12 females and 9 males, mean age pre-treatment: 14.7 +/- 1.50 years) were treated with the 3D-BMDA and 17 (14 females and 3 males, mean age pre-treatment: 14.4 +/- 1.43 years) with the MBIDS. Measurements were recorded from lateral cephalometric radiographs taken at two different points in time: at the start of treatment for the MBIDS group and prior to distalization for the 3D-BMDA group (T1) and post-distalization (T2). Student's t- and paired t-tests were used to determine differences between and within the groups. The total amount of distalization for the 3D-BMDA and MBIDS groups was similar (3.55 and 3.27 mm, respectively). However, there were statistically significant differences in the length of the distalization period (3.4 and 6.5 months, respectively) and the amount monthly of distalization (1.11 and 0.54 mm, respectively). The most significant differences were observed in the mandibular dental arches and vertical facial dimensions. Anchorage loss in the mandible was greater in the 3D-BMDA group, whereas increases in facial dimensions were greater in the MBIDS group. Both 3D-BMDA and MBIDS techniques were found to be effective to obtain distal movement of the maxillary molars. In order to achieve successful results, the side-effects of each treatment modality on dentofacial structures need to be taken into consideration.