铸造Nance弓在拔牙后上尖牙自由调整病例中的应用

Casting Nance arch which allowed the upper canine's self-adjustment in the extraction cases

目的 :研究拔除上颌第一前磨牙后上尖牙自行调整效果及铸造Nance弓在维持上颌第一磨牙位置中的作用。方法:选择20例上颌尖牙唇侧错位、中度或重度拥挤的年轻患者,确定治疗方案后拔除上颌双侧第一前磨牙,制作个性化铸造Nance弓并粘结固定在双侧上颌第一磨牙,观察6个月后进行测量并开始固定矫治。采用Graphpad Prism 6.0软件对所得数据进行配对t检验。结果 :所有患者尖牙均发生明显移动[(3.6±0.1)mm,P<0.01];上颌第一磨牙位置基本稳定[(0.2±0.16)mm,P>0.05]。结论:拔除上颌双侧第一前磨牙有利于唇侧错位尖牙自行调整到牙弓弧度内,铸造Nance弓能维持自行调整阶段双侧上颌第一磨牙的位置。

PURPOSE： To study the upper canine＇s self-adjustment after the first premolar extraction and the effect of casting Nance arch in the sustainment of the upper first molar position. METHODS： Twenty severely crowded adolescents whose upper canines were in labial malposition were chosen. After the treatment plan was made, the upper first premolars were removed, the individually made casting Nance arches were fixed on the upper first molars. The measurement and fixed orthodontic treatment began 6 months later. Graphpad Prism 6.0 software was used for data analysis. RESULTS：The average movement of the malpositioned canines was（3.6±0.1）mm（P〈0.01）; while the forward movement of the first molars was（0.2±0.16）mm（P〉0.05）. CONCLUSIONS： Extraction of the first premolars is beneficial to the canine＇s selfadjustment in adolescents and the casting Nance arch could help keeping the first molar＇s positions.