Abstract:

Objective    To observe the clinical effects of PASS appliance Anchorage Control technique in the treatment of adolescents with severe crowded malocclusion. Methods    Seventeen patients with Class Ⅰ or Class Ⅱ malocclusion  and severe crowded teeth were included. They were extracted 4 first premolars and treated with PASS appliance without extra anchorage appliance. Analysis was carried out on the results before and after treatment. Results    The average treatment time was 16 - 24 months. After treatment，normal overbite and overjet were achieved and good occlusal relationship and profile were attained. Significant change was found after treatment. Cephalometric measurements showed that U1-SN decreased by 12.5°，L1-MP decreased by 3°，U1-L1 increased by 6.5°，and LL-E decreased by 1mm. Significant difference was found in all these measurements before and after treatment. Conclusion    PASS appliance Anchorage Control technique can be used in the treatment of patients with severely crowded malocclusion with significant effect.

Key words: PASS appliance Anchorage Control technique, adolescent, severe crowded malocclusion

摘要：

目的    应用生理性支抗控制技术对青少年重度拥挤的错牙合畸形患者进行矫治，观察分析矫治效果。方法    选择2013年8月至2014年9月在安康市中医院口腔科就诊的牙列重度拥挤的安氏Ⅰ类、Ⅱ类错牙合畸形患者17例，在拔除4颗第一前磨牙后，应用生理性支抗控制技术进行矫治，对治疗前后结果进行分析。结果    17例患者在未增加任何辅助支抗的情况下，矫治疗程16 ～ 24个月。矫治结果显示，牙列拥挤解除，尖牙、磨牙关系中性，覆牙合、覆盖正常，面型良好。与矫治前比较，矫治后头影测量显示，上中切牙与前颅底平面相交的内下角（U1-SN）、下中切牙长轴与下颌平面相交的内上角（L1-MP）、下唇突点到审美平面的距离（LL-E）显著减小，上、下中切牙长轴的交角（U1-L1）显著增加，差异均有统计学意义（P＜0.05）。 结论    生理性支抗控制技术对矫治生长发育期的青少年重度牙列拥挤患者效果较好。

关键词: 生理性支抗控制技术, 青少年, 重度拥挤