Three-dimensional evaluation of skeletal changes in patients with class II malocclusion treated with forsus appliance: CBCT study

The aim of this study was to evaluate the skeletal changes in patients with Class II malocclusion treated with Forsus (Forsus Fatigue Resistant Device, 3M Unitek) appliance by using three-dimensional images of cone-beam computed tomography (CBCT). The study consisted of patients who applied to Çukurova University, Faculty of Dentistry, Department of Orthodontics and treated with a fixed functional appliance. The study sample consisted of 35 subjects which has 3D images of computed tomography before placement and after removal of Forsus appliance. The subjects were divided into two groups based on their different growth pattern: The age of 13-14 is peak phase of pubertal growth (Peak pubertal group) and the age between 15-17 is late phase of pubertal growth (late pubertal group). The patient selection criteria were as follows: Skeletal Class II dental Class II Division 1 malocclusion, patients with the age between 13-17 during the CBCT imaging, no missing permanent teeth, no mandibular deviation, no temporomandibular joint problems, no systemic diseases, ANB angle greater than 4° and overjet greater than 5 mm. It can be seen that the Forsus appliance has an stimuli effect on mandibula in both groups; but more in peak pubertal group based on the 3D images which were taken before placement and after removal of the appliance. There were no sagittal skeletal effect on maxilla. There were no vertical changes for two groups. Both maxillary incisors were retruded and mandibular incisors were protruded in two groups. The changes were more intensive in late pubertal group. The results revealed that, in patients with Class II malocclusion, Forsus appliance has an positive skeletal effect but in late pubertal group, this skeletal effect was limited.