Objectives: The aim of study was to evaluate skeletodental and soft tissue treatment effects and the amount of maxillary molar distalization with modified C-palatal plates vs. Greenfield molar distalizer appliances in adolescents. Study design: The samples consisted of pre- and posttreatment lateral cephalograms collected from 39 patients with Class II malocclusion. The MCPP group was comprised of 21 patients (mean age: 11.7 ± 1.3 years) treated with MCPP appliances while the GMD group included 18 patients (mean age: 11.2 ± 0.9 years) treated with GMD. Fixed orthodontic treatment started with the distalization process in both groups. From each cephalograpm, twenty-nine variables were measured for analysis and then the two groups were compared. Descriptive statistics, a paired t-test, and multivariate analysis of variance were performed to compare the treatment effects within and between the groups. Results: There was significant treatmentrelated change in the sagittal position of the maxilla and the mandible within each group. However, there were no statistically significant inter-group differences. The mean maxillary first molar distalization was 3.96 mm in the MCPP group vs. 2.85 mm in the GMD group. Both groups showed minimal distal tipping, but the maxillary incisors were significantly extruded by 3.04 ± 0.89 mm (P < .001) in GMD group. There was no significant difference in treatment duration between the groups.
Conclusions: The maxillary first molars of both the MCPP and GMD groups were effectively distalized and there were significant skeletal changes in the maxilla. However, the maxillary incisors were significantly extruded in the GMD group.