ABSTRACT
Objective:To compare the effects between Begg and pre-adjusted appliance on dentofacial morphology in Angle class Ⅱ division 1 extraction cases treated by light archwire technique.Methods:28 cases with Angle class Ⅱ division 1 who needed maximum maxillary incisor retraction were divided into 2 groups (MBT pre-adjusted and Begg group) and treated by light archwire technique.4 first premolars were extracted in all patients.Lateral cephalometric films were analyzed before and after treatment.Results:The upper incisors were intruded (0.18 ± 0.32)mm and (0.77 ± 0.91) mm in pre-adjusted and Begg group respectively (P ＜ 0.05).The other differences of cephalometric analyses between 2 groups were not significant (P ＞ 0.05).Conclusion:The effects were almost same with pre-adjusted and Begg appliances in Angle class Ⅱ division 1 extraction cases treated by light archwire technique except for that the latter is better than the former in vertical control of maxillary anterior teeth.