Comparative Evaluation Of Clinical Effects Between Herbst Appliance And Fixed SGTB Appliance Orthopedics On Angle Class Ⅱ Division Ⅱ

PURPOSE: The purpose of this retrospective study was to compare the skeletal and dental effects between Herbst appliance and SGTB appliance in Angle Class Ⅱ, Division 2 malocclusion,in order to provide the evidence of which orthopedic appliance to choose in the treatment of Angle Class Ⅱ, Division 2 malocclusion.METHODS: The sample comprised of 15 subjects with Class Ⅱ Division 2 malocclusion, treated with orthopedic appliance followed by fixed edgewise appliance, including 8 cases treated with Herbst appliances and 7 cases treated with SGTB appliances. Cephalometric radiographs were taken before(T0), during(T1)and after(T2)the treatment. Cephalometric parameters were analyzed statistically and intragroup and intergroup changes were evaluated by t-tests,using SPSS 20.0 for windows.RESULTS: After the treatment of Herbst appliance(Ta1), the increase of U1//SN、U1//PP and L1//MPA displayed significant difference(P<0.05). After the two-stage treatment of Herbst(Ta2), the decrease of SNA、ANB and the increase of U1//SN、U1//PP、L1//MPA displayed significant difference(P<0.05). After the treatment of SGTB appliance(Tb1), the decrease of ANB and the increase of U1//SN、U1//PP、L1//MPA displayed significant difference(P<0.05). After the two-stage treatment of SGTB(Ta2), the decrease of ANB and the increase of SNB、U1//SN、U1//PP、L1//MPA displayed significant difference(P<0.05). The intergroup difference of two groups at the time of T0、T1、T2 showed no statistically significant results(P>0.05).CONCLUSION: For Class Ⅱ Division 2 malocclusion cases with growth potential,SGTB exert more mandible advancement than Herbst appliance. After the first stage of orthopedic therapy, Herbst appliance cause more unfavorable lower incisor proclination than SGTB.