种植支抗关闭正畸拔牙间隙对上颌磨牙垂直向高度的影响

目的：研究种植支抗联合滑动法内收前牙间隙过程中上颌磨牙垂直向的改变。方法选择25例成人患者，根据治疗需要拔除上颌第一双尖牙，在上颌5、6之间植入种植钉，作为支抗内收前牙关闭间隙。将患者治疗前后的数字化模型进行重叠，比较上颌第一、第二磨牙的垂直向改变。结果上颌第一磨牙治疗后被压低（P<0.001），第二磨牙没有明显改变。上颌第一磨牙的近中舌尖、远中舌尖、近中颊尖、远中颊尖四个牙尖的改变无显著性差异。结论使用种植支抗联合滑动法关闭正畸拔牙间隙，将会导致上颌第一磨牙的压低，但是第二磨牙没有显著改变，并且第一磨牙没有明显的颊侧倾斜。

Vertical dimensional change of upper molars in extraction orthodontic treatment with micro-screw anchorage

Objective To investigate the vertical dimensional change of upper molars treated with micro-screw anchorage after upper first premolar extraction.Methods Twenty-five adult patients were selected. Their maxillary first premolars were extracted according to the treatment protocol, and the space was closed with sliding mechanics and micro-screws anchorage. The mathematic models of pre- and post-treatment were superimposed, and the vertical dimensional changes of upper molars were calculated.Results The upper first molars were intruded after treatment (P<0.001), but the upper second molars did not change significantly. There was no significant difference between the cusps of the upper first molars.Conclusion The upper first molars were intruded but not inclined buccally when the space was closed with micro-screw anchorage, and the upper second molars were not obviously intruded.