安氏Ⅰ类拥挤拔牙病例软组织侧貌变化

目的　探讨安氏I类错牙合牙列拥挤经拔除 4个第一前磨牙矫治前后牙颌面软组织的变化 ,了解矫治对软组织变化的影响。方法　选择泸州医学院附属口腔医学院正畸科连续收治的安氏I类错牙合牙列拥挤患者 19例 ,采用拔除 4个第一前磨牙 ,用标准方丝弓技术矫治。在矫治前、后摄X线头颅定位侧位片 ,对 11个软组织标志点的变化进行分析。结果　H角平均减少 2 .4°(P <0 .0 5 ) ;软组织面角平均增大 3.2 8°(P <0 .0 5 ) ;颏唇沟深度平均增加 1.0 8mm(P <0 .0 5 )。结论　安氏I类错牙合牙列拥挤经拔除 4个第一前磨牙矫治后软组织变化主要表现在上唇相对于面前软组织的前突度减少

Study of esthetic characteristic changes of soft-tissue profile of children with angel class I malocclusion treated by orthodontic extraction

Objective To evaluate the effect on the changes in the soft-tissue profile of the children treated by orthodontic extraction, and investigate the changes in the soft-tissue profile before and after treatment in Class I malocclusion with crowding treated by extraction of four first premolars. Methods 19 patients with Angel Class I malocclusion, including 7 males and 12 females, aged from 14 to 16 years old, were treated by extracting the four first premolars with Edgewise appliance. The individual normal occlusion was achieved when the orthodontic treatment completed, pretreatment and post treatment of cephalograms of every child were traced to analyze the esthetic characteristic changes of soft-tissue profile, and eleven landmarks of the facial soft-tissue were selected and analyzed. Results H angel was reduced by 2.40 mm on average(P<0.05); the facial convexity angel (FCA) increased by 3.28° on average (P<0.05). The depth of the inferior labial sulcus increased by 1.08 mm on average(P<0.05). Conclusion In Angel Class I malocclusion with crowding treated by extraction of four first premolars, the changes of the soft-tissue profile are mainly caused by reduction of the upper lip(ULP).