上颌第一磨牙控制的生物力学研究  

Biomechanical analysis of the maxillary first molar control

作　　者：苏晓霞[1] 杨梅 周洪[1] SU Xiao-xia YANG Mei ZHOU Hong(Clinical Research Center of Shanxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi＇ an Jiaotong Uni- versity, Xi＇ an 710004, China)

机构地区：[1]陕西省牙颌面疾病临床研究中心、西安交通大学口腔医学院正畸科,陕西西安710004 [2]陕西省交通医院口腔科,陕西西安710068

出　　处：《中国实用口腔科杂志》2016年第12期725-729,共5页Chinese Journal of Practical Stomatology

基　　金：陕西省资源主导型产业关键技术(链)项目基金(2016KTCL03-13)

摘　　要：目的利用三维有限元方法模拟在上颌第一磨牙加载不同角度及位置的后倾曲和末端内收曲时,其受力分布规律和位移趋势,并阐明其生物力学机制。方法建立上颌全牙弓三维有限元模型。(1)使用0.018英寸×0.025英寸(0.48 mm×0.64 mm)不锈钢方丝在不同部位建立弯折15°、30°及45°后倾曲弓丝模型。观测不同工况下上颌第一磨牙在Z向的位移;(2)在不同部位建立弯折15°、30°以及45°Toe-in曲弓丝模型,观测不同工况下上颌第一磨牙在X和Y向的位移情况。结果 (1)后倾曲弯折的角度增加,第一磨牙受到净力随之增加;弯折点越靠近第一磨牙近中,其压入力量越大;弯折点靠近第二前磨牙时,磨牙呈整体伸长趋势。(2)Toe-in曲弯折角度增加,第一磨牙的旋转位移角度随之增加;Toe-in曲弯折点靠近第一磨牙颊面管近中时,第一磨牙呈整体舌向位移;弯折点靠近第二前磨牙时,呈顺时针旋转趋势。结论后倾曲对第一磨牙垂直位移影响较大,其弯折点靠近第二前磨牙时有利于支抗控制及咬合打开;Toe-in曲的弯折则有利于平衡第一磨牙旋转的副作用。Objective To investigate the distribution and initial displacements of the maxillary first molar under various degree and location of tip back and Toe-in bends by the 3-D finite element method, so as to clarify the biomechanism of those bends. Methods （ 1 ）The whole maxillar 3-D finit element model was successfully constructed. 0.018×0.025 wire was used in this study. Analyze the displacement of upper first molar when there were 15°, 30° and 45° tip baek bends in different location. When the forces were loaded in these situations on the model, observe the upper molar displacement on the Z directions. （2）Analysze the displacement of upper first molar when there were 15°, 30° and 45° Toe-in bends in different location. When the forces were loaded in these situations on the model, observe the upper molar displacement on the X and Y directions. Results （ 1 ） With the increase of the tip back bends angle, the magnitude of the bending force increased. As bend location progressively moved toward the molar, the magnitude of the intrusive moment at the molar also progressively increased. When the bend was close to the second premolar, the first molar showed an extensive movement.（2）With the angle of the Toe-in bends increaing, the magnitude of force increased. When the bend was close to the upper first molar, it showed the overall lingual displacement. When the Toe-in was near the second premolars, the upper molar had a clockwise rotation. Conclusion Tip back bend is critical in controlling vertical dimension of thefirst molar, and is beneficial to anchorage control and bite opening when located in distal of the sec- ond premolar. Toe-in bend is in favour of rotation control of the first molar.

关 键 词：三维有限元 磨牙控制曲 位移 

分 类 号：R78[医药卫生—口腔医学]