ABSTRACT

With the purpose of investigating the effect of cervical headgear on the cant of the occlusal plane; 7 males and 13 females as the experimental group, 7 males and 13 females as the control group summing up to a total of 40 individuals were included in this study. The experimental group was composed of 20 subjects whose cronological age mean was 9 years 11 months and 13 had skeletal class 1 structures where the remaining 7 had skeletal 2 structures and all had clinically diagnosed as Angle Class II, 1 malocclusion cases while the lack of space in the upper area was lower than 6 mm. In order to be able to identified the difference which might occur by growth and development, a control group of 20 subjects of which 13 had skeletal class 1. the remaining 7 had skeletal class 2 structures, was included in the study Cervical Headgear which the outher bows ended at the projection of the distal points of the upper first permanent molars were bent parallel to the occlusal plane was applied to the experimental group. Extraoral force of 600 gr. was applied for 16 hours per day. A total of 80 cephalometric radiogrophs of all subjects included in this study were taken before and after the research period. The SN / Occ. plane angle which indicates the cant of occlusal plane was traced on the cephalometric radiographs. The cephalometric radiographs taken before and after the research period were locally registered for both maxilla and mandibula separately. Distal bodily movement of upper first molars was found to be statistically significant, while the upper incisors' downward and backward, lower first permanent molars' upward and forward movements and finally lower incisors' extrusions, in both groups, were not found to be statistically significant. The reduction in the cant of occlusal plane was statistically significant in the control group. Since, this was not the case for the experimental group, as the result of this study, it was concluded that the effect of cervical headgear on the cant of ocllusal plane was statistically significant.