Treatment effects produced by preorthodontic trainer appliance in patients with class II division I malocclusion.

The aim of the present study was to evaluate cephalometrically the treatment effects of preorthodontic trainer on dentoskeletal components in individuals showing class II division I malocclusion. This study comprised of 50 class II div. I patients (20 test patients and 30 controls) in the age group of 8-12 years. The test group was treated with a preorthodontic trainer for a period of 15 months. Standardized lateral cephalograms of both groups were taken before and after the treatment period. The cephalograms were then evaluated to determine the skeletal and dental changes in the course of treatment and then compared with the normative growth data to eliminate the possible growth effects. The readings were tabulated and subjected to statistical analysis. The results of the study after excluding the changes due to growth showed reduction in ANB and OP-SN values, indicating a significant reduction in the skeletal class II relationship. An upward cant of the occlusal plane in the treatment group was noted, probably due to the forward rotation of mandible. A significant increase in the vertical dimensions of the face in general and the mandible in particular was observed with the use of preorthodontic trainer. A significant reduction in the overjet and an increase in the inclination of mandibular incisor (L1-NB deg) were noted in the treatment group when compared with control group. It can be concluded that class II corrections can be achieved with the preorthodontic trainer appliance, which appears to have mostly dentoalveolar effects with smaller but significant skeletal effects.