口内支抗与微型种植体支抗近中移动下颌磨牙效果比较

目的：研究安氏I类错（牙合）患者中,分别采用微型种植体作支抗与口内前牙作支抗近移下颌磨牙进行比较,以评价两种方法的各自特点。方法：将24例成人患者随机分成两组,分别采用两种方法近移下颌磨牙。测量下颌第二磨牙在移动速度和近远中方向、垂直方向的位置变化,以衡量磨牙的位置改变,并通过下颌中切牙的位置变化,评价支抗强弱。结果：种植体作支抗组下颌第二磨牙平均近中移动8.5mm,疗程10.4个月,平均移动速度0.82mm/月,磨牙长轴向近中倾斜2.5°,磨牙垂直向压低0.28mm,下颌中切牙位置无改变。对照组下颌第二磨牙平均近中移动7.8mm,疗程10.2个月,平均移动速度0.76mm/月,磨牙长轴向近中倾斜角度7.5°,磨牙垂直向压低0.06mm,下颌中切牙发生舌向倾斜9.5°。下颌中切牙切端向舌侧移动了3.0mm。结论：两种方法比较,种植体的支抗更强,未见前牙支抗丧失。二者磨牙的移动方式有所区别。

Comparison of mesializing mandibular molar by micro implant anchorage and intraoral anchorage

Objective To evaluate characters of micro-implant anchorage and intraoral anchorage during mandibular molars mesialization in Class I malocclusal patients. Methods 24 patients were divided into two groups equally. Measuring position changes of mandibular molars from 2 aspects and implant anchorage loss by mandibular central incisor. Results In implant anchorage group： the velocity of mandibular second molar mesializing was 0.82 mm per month, mesial tipping 2.5° , mandibular central incisor do not move.In intraoral anchorage group： the velocity of mandibular second molar mesializing was 0.76 mm per month, mesial tipping 7.5° , mandibular central incisor move bucally 3.0mm. Conclusion Two methods successfully mesialized maxillary molars to appropriate positions. But implant anchorage is stronger than another. Then move mode of mandibular molar differenciate from each other.