腭杠腭托联合支抗矫治双颌前突的临床研究

Transpalatal-Nance arch on reinforcing anchorage: A clinical study on bimaxillary protrusion

目的：通过研究不依赖于患者配合的腭杠腭托口内支抗系统矫治双颌前突的临床疗效分析其支抗作用．方法：选取12～26岁安氏Ⅰ类双颌前突患者34例，均在拔除4个第一前磨牙后，应用标准方丝弓固定矫治技术治疗，支抗设计采用腭杠腭托联合支抗系统（横腭杆＋Nance弓）；分析治疗前后X线头颅侧位定位片以及牙颌研究模型的各项指标变化．结果：磨牙平均前移（1．50±0．85）mm，但未达到拔牙间隙的1／3；上下切牙平均内收量分别为（4．73±2，64）mm和（5，52±4，62）mm；双颌前突软组织侧貌有较大改善（Ls-E，Li-E，Cm-Sn-Ls，Pg’B＇-FH，A’Ls-FH，Z角的改变，P〈0．01）；磨牙伸长量有统计学意义（P〈0．05），但下颌平面角、面高比以及后牙弓宽度改变没有显著性（P≥0．05）；上下牙槽骨的变化没有显著性（P≥0．05）．结论：腭杠腭托联合支抗系统对于矢状向、垂直向、水平向支抗控制较好，是一种简单有效的非依赖性口内强支抗系统；对于矫治双颌前突拔牙病例是一种非常有效的强支抗．

AIM： To study the effect of transpalatal-Nance arch on reinforcing anchorage in the treatment of bimaxillary protrusion. METHODS： A total of 34 patients （aged 12 -26 years） with Class Ⅰ malocclusion and bimaxillary protrusion were selected and treated with the transpalatal-Nance arch on reinforcing anchorage after the extraction of first premolar in each quadrant. Lateral cephalometric radiographs and casts were taken before and after treatment for analysis. RESULTS： The average forward movement of the first maxillary molar was （ 1.50 ± 0.85 ） mm, but still less than 1/3 of the extraction space. The changes in the backward movement and reduction of the axial inclination of the incisors were significant and the average backward movements of the upper and lower incisors were （4. 73± 2. 64） mm and （5.52±4.62） mm respectively. The soft tissue profile （Ls-E, Li-E, Cm-Sn-Ls, Pg＇B＇-FH, A＇L s-FH and Z angle） was greatly improved （ P 〈 0.01 ）. The vertical distance of the first maxillary molar to the palatal plane was increased （ P 〈 0.05 ） , but the changes in GoGn-Sn angle and ALFH/AFH were not significant （P≥0.05）. The changes of the alveolar bone （ SNA, SNB and ANB） were not significant （ P ≥0.05 ）. CONCLUSION： The transpalatal-Nance arch anchorage system is an effective and simple anchorage with three-dimensional anchorage function. It can be used as a noncooperative strong anchorage in the treatment of bimaxillary protrusion.