隐适美隐形矫治器远移上颌磨牙的效能评价

Evaluation of the efficiency of Invisalign aligner for maxillary molar distalization

目的比较使用隐适美隐形矫治器远移上颌磨牙前后的数字化牙合模型,并评价其效能。方法选取2017年7月至2019年7月在江门市口腔医院就诊的50例使用隐适美隐形矫治器患者,均采用非拔牙且远移上颌磨牙的方案,使用iTero口内扫描仪获得矫治前和远移磨牙后的数字化上颌模型。使用ClinCheck软件设计矫治方案,从中获得远移磨牙后目标位置的数字化模型。通过Geomagic studio 12软件进行模型重叠配准,测量牙齿的目标移动量和实际移动量,并通过SPSS20.0统计软件分析磨牙远移效能。结果双侧上颌第一、第二磨牙的远移量均小于目标远移量(P<0.05)。上颌第二磨牙的远移效能为(80.52±8.21)%,上颌第一磨牙的远移效能为(78.57±5.37)%。远移上颌磨牙时,磨牙会出现牙冠颊向移动、压低、远中轴倾度和颊向转矩增加。远移上颌磨牙时,上颌前牙会出现牙冠唇向移动和唇向转矩增加。结论隐适美隐形矫治器能有效远移上颌磨牙,但会造成上颌前牙唇倾,提示临床设计远移磨牙时可适当增加支抗,比如增加牵引或辅助种植钉。

【Objective】To evaluate the efficiency of maxillary molar distalization on Invisalign aligner with digital models before and after distalization.【Methods】Fifty patients with Invisalign aligner were selected in our hospital from July 2017 to July2019.The maxillary digital models before and after molar distalization were obtained by iTero intraoral scanner.The orthodontic treatment was designed by ClinCheck software,from which the digital models of the target position after molar distalization were obtained.Geomagic studio 12 software was used for model registration to measure the target movement and actual movement of teeth,and SPSS 20.0 was used to analyze the efficiency of maxillary molar distalization.【Results】The actual distalization of bilateral maxillary first and second molars was less than the target distalization.The efficiency of maxillary second molar distalization was(80.52±8.21)%.The efficiency of maxillary first molar distalization was(78.57±5.37)%.The crown of molars tend to have a buccal,intrustion movement and decrease in tip and increase in buccal torque when distalizating.The crown of maxillary anteriors tend to have a labial movement and increase in labial torque when distalizating maxillary molars.【Conclusion】Invisalign aligner can effectively distalize maxillary molars,but it can cause labial inclination of maxillary anteriors,suggesting that anchorage can be properly used in the design of molar distalization,such as elastics or temporary anchorage devices.