两种扩弓方法结合前方牵引的临床效果比较性研究

目的 评价上颌反复快速扩缩结合前方牵引与单纯上颌快速扩弓结合前方牵引在治疗上颌发育不足骨性Ⅲ类患者的临床疗效。 方法 选择34例上颌发育不足的骨性Ⅲ类儿童，随机分成两组：观察组17例，采用上颌反复快速扩缩结合前方牵引，并分为低角和高角两组；对照组17例，采用单纯上颌快速扩弓结合前方牵引。对所有病例治疗前后均拍摄头颅侧位片进行投影测量分析。 结果 两组病例扩弓并进行前方牵引后上颌显著前移，下颌向下后方旋转，两组间对比：观察组A-Np和A-Y的距离分别增加了2.50 mm和3.47 mm，大于对照组的1.37 mm和2.05 mm。 结论 使用上颌反复快速扩缩法结合前方牵引的治疗方法比单纯上颌快速扩弓结合前方牵引的方法获得更多的上颌前移量。此方法中高角患者上颌前移量少于低角患者。

A comparative study on maxillary protraction therapy with two different methods of rapid palatal expansion

Objective To evaluate the clinical effects of maxillary protraction with repetitive rapid expansion and constriction or maxillary protraction with rapid expansion only on treating skeletal class III patients with maxillary dysplasia.Methods 34 cases of skeletal class III children with maxillary dysplasia were randomly divided into two groups:the observation group and the control group.The observation group contained 17 cases treated with maxillary repetitive rapid expansion and constriction combined with maxillary protraction,which were further divided into the low angle group (12 cases) and the high angle group (10 cases).The control group contained 17 cases treated with simple rapid maxillary expansion combined with maxillary protraction.Cephalometric radiographs of all cases were taken before and after treatment,and data were given projection measurement analysis.Results Anterior displacement of maxilla,as well as downward and backward rotation of mandible was found after maxillary protraction in both groups.To compare the two groups:in the observation group,A-NP and A-Y distance increased by 2.50 mm and 3.47 mm respectively,which were greater than 1.37 mm and 2.05 mm in the control group.Conclusions Maxillary repetitive rapid expansion and constriction combined with maxillary protraction can obtain larger amount of anterior displacement in maxilla than simple rapid expansion combined with maxillary protraction.Besides,the former had more effect on the low angle patients.