拔除下切牙矫治在改善Bohon指数中的作用

目的：探讨拔除下颌切牙进行矫治，通过改变Bolton指数来进行代偿治疗中的作用。方法：采用回顾性研究的方法，对9例由于各种原因需拔除单个下颌切牙或配合拔除其它牙齿进行矫治的病例进行分析比较。结果：9个病例矫治时间为19-23个月，均采用直丝弓矫治技术。治疗结束后拔牙间隙均全部关闭，前牙覆胎覆盖关系基本正常，后牙咬耠关系较好。结论：部分上颌需要减数的成人骨性Ⅱ类病例，下颌可以考虑拔除一个下切牙矫治；某些轻、中度的成人骨性Ⅲ类患者也可拔除一个下切牙结合上颌邻面去釉进行矫治。拔除下颌切牙矫治在诊断设计时应权衡利弊，严格控制适应症，以获得良好、稳定的矫治效果。

The effect of lower incisor extraction on anterior ratio of Bolton index.

Objective： To investigate the effect of lower incisor extraction on Bohon index. Method： A retrospective study of 9 orthodontic patients who had lower incisor extractions was carried out.Records representing pretreatment and post- treatment included cephalogram,panoramic films, intraoral and extraoral photographs, and plaster models .Electronic vernier caliper was used to measure the tooth size on the dental cast for each patients. Result：Total treatment time was 19-23 months. All extraction space was closed after the treatment. All patients achieved satisfactory treatment results, good occlusal relationship and soft tissue profile. Conclusion.. To be well prudent with the indications of the extraction of the lower incisor in orthodontic treatment of malocclusions, flexibly choose the treatment objective, can be helped to achieve satisfactory effect.