前方牵引治疗替牙期骨性Ⅲ类错的牙颌结构变化研究

目的:观察前方牵引在替牙期骨性Ⅲ类错牙合的应用及治疗前后的牙颌结构变化。方法:选择替牙期骨性Ⅲ类错牙合患者9名,应用前方牵引矫治前牙反牙合,正畸前后进行头影测量分析。统计学分析采用配对t检验。结果:SNA角增大4.2°,ANB角增加5.4°,NA-PA增加5.0°,A-VL增加6.1mm,SNB角减少1.2°,B-VL减少0.2mm,1-SN增加6.2°。结论:前方牵引可有效促进上颌骨向前生长,抑制下颌骨生长,同时可导致下颌骨向下向后旋转,上前牙唇倾,下切牙轻度舌倾。

Destoalveoler changers in skeletal Class III patients after maxillary protraction in the mixed dentition.

Objective:To evaluate the changes in skeletal Class III patients after maxillary protraction in the mixed dentition. Method :Nine skeletal Class III patients in the mixed dentition were selected. The age range of the patients was from 7.0 to 11 years. The malocclusions of the patients included anterior crossbite and underdeveloped maxilla,The cephalometric records were analyzcd to assess the dentoalveolar changes before and after heatment. Result:The skeletal changes consisted of maxillary anterior displacement and mandibular downward and backward rotation. Improving facial profile. Dental alterations comprised a tendency of labial tipping of the maxillary incisors lingual tipping of the mandibular incisors. Conelusion:Protraction is effective in the correction of skeletal Class III malocclusion in the mixed dentition and skeletal pattern can be improved.