The comparison of incisor position and profile changes of class II caces, that were treated by extracting both upper and lower first premolars, upper first premolars and servical headgear treatment without extractions

SUMMARY The purpose of this study, was to investigate and compare the changes occur, during the treatment with edgewise mechanics by extraction of only first maxillary premolars, both maxillary and mandibular first premolars and by using cervical headgear without extraction. The soft tissue facial profile and incisor position changes were compared biometrically on lateral cephalograms which were obtained both at the beginnig and at the end of treatment. The mean age of the cases at the beginning of the treatment in maxillary and mandibular first premolar extraction group was 13.47 ± 1.63 years and mean treatment period was 1.8 ± 0.53 years. 7 of the cases were females and 6 were males.The mean age of the cases at the beginning of the treatment in maxillary first premolar extraction group was 14.12 ± 1.92 years and mean treatment period was 1.5 ± 0.42 years. 8 of the cases were females and 5 were males. The mean age of the cases at the beginning of the treatment in cervical headgear group was 13.98 ± 1.72 years and mean treatment period was 1.7 ± 0.48 years. Pretreatment and post treatment changes occured in three groups were compared by means of Wilcoxon test. ANOVA and Duncan tests were used for intergroup comparison. In all three groups, the status of both hard and soft tissue facial profile improved and soft tissue followed the changes in both bony and dental structures in respective ratios. The soft tissue profile changes in maxillary and mandibular first premolar extraction group were significantly different from the other two groups. Increase in GoGnSN angle in cervical headgear group was statistically important while in extraction groups no statistical difference was obtained. mKey words: Class II Division 1 malocclusion, treatment with extraction, profile change. IV