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目的:建立微种植体-直丝化舌侧矫治系统内收上颌前牙的三维有限元模型,分析微种植体处于不同植入高度时上前牙的位移趋势及应力变化,为舌侧矫治临床应用提供一定的生物力学参考.方法:利用锥形束CT扫描片建立上颌骨、上颌牙列、牙周膜的三维几何模型,分别在第一磨牙与第二磨牙之间,距牙槽嵴顶4mm、8mm和12mm处植入微种植体,建立微种植体-直丝化舌侧矫治内收上颌前牙的有限元模型.分析同时施加唇侧压低力和舌侧回收力后上前牙的位移及应力变化.结果:内收前牙的过程中,前牙均表现出了一定程度的冠舌向倾斜,随着腭侧微种植体高度的增加,前牙冠舌向倾斜移动逐渐减小,中切牙较侧切牙及尖牙的变化最为显著.当微种植体高度为8mm时,上前牙的牙根及牙周膜应力最小.结论:在舌侧矫治中,关闭拔牙间隙阶段选择恰当的腭侧微种植体植入高度同时应用适当的唇侧压低力可有效控制前牙转矩.“,”Objective:To establish the three-dimensional finite element models of micro-implants-lingual straight wire about anterior teeth retraction;and to analyze the teeth movement tendency with different micro-implant heights for providing the biomechanical reference for clinical application of lingual orthodontics.Methods:Three dimensional model of maxilla, teeth, and periodontal ligament was obtained by CBCT scan.The palatal micro-implants between first and second molars were set respectively with different heights (4mm, 8mm and 12mm) from the alveolar crest.The obtained three-dimensional finite element models of micro-implants-lingual straight wire were used to analyze the teeth movement tendency and stress changes when labial intrusion force and lingual retraction force were applied.Results:All of the anterior teeth showed a degree of buccal root torque during the retraction.With the increase of palatal micro-implant height from the alveolar crest, the tendency of the buccal root torque of anterior teeth were significantly reduced, and the change of central incisors was the most obvious compared with the lateral incisors and canines.When the height of micro-implant was 8mm, the root and periodontal ligament stress was the minimum.Conclusion:It can effectively control the anterior teeth torque during the retraction in the lingual orthodontics treatment by choosing the right height of micro-implant and applying the labial intrusion force in anterior teeth.