微种植体支抗结构的有限元计算分析  

NUMERICAL ANALYSES OF BIOMECHANICAL BEHAVIOR OF ORTHODONTIC ANCHORAGE MINI-IMPLANTS USING FINITE ELEMENT METHOD

作　　者：陈宏伟[1] 安晓莉[1] 王记增[1] 周又和[1] 

机构地区：[1]西部灾害与环境力学教育部重点实验室,兰州大学土木工程与力学学院,甘肃兰州730000

出　　处：《固体力学学报》2013年第S1期126-131,共6页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(11032006;11072094和11121202);教育部新世纪优秀人才支撑计划项目(NCET-10-0445);教育部博士点基金项目(20100211110022);兰州大学中央高校基本科研业务费专项资金(lzujbky-2012-202;lzujbky-2013-228)资助

摘　　要：在正畸治疗过程中,正确地进行支抗控制是影响正畸效果的关键因素.传统支抗因其异物感强、美观度差、结构复杂等缺点,在临床上不容易获得理想的治疗效果.由于体积小、结构简单、配合度高等优点,微型支抗种植体(Orthodontic Anchorage Mini-implant)很好的克服了上述缺点,在临床上得到了广泛的应用.本文通过建立微螺钉种植体支抗、皮质骨组织、松质骨组织的三维有限元模型,模拟了在不同方向外载荷作用下,不同长度微种植体支抗及其与牙槽骨结合处的应力分布.由于与骨结合处的应力与变形大小会影响微种植体的稳定,我们由此结合多个工况计算研究了长度对微螺钉种植体支抗稳定性的影响.分析结果表明:在正畸临床治疗的过程中应当尽量使用与微螺钉种植体支抗轴线呈较小或者较大的角度的正畸力,这样能提高微种植体支抗的稳定性;通过增加微螺钉种植体支抗的主体长度能有效地降低骨结合处的最大正应力,提高稳定性,然而当微种植体支抗的主体长度超过11毫米时,应力降低的效果不再明显.这些对今后的口腔正畸临床治疗以及相关产品的优化设计都有着重要意义.Anchorage control is a major factor that affects the orthodontic treatment.However,traditional anchorages usually have poor aesthetics and complex structures,and may make patients have strong foreign body sensation;therefore they may fail to induce desired therapeutic effect in clinical treatment.Orthodontic anchorage mini-implants have properties of small size,simple structure and high degree of adaptability.These properties have just remedied the shortages of the traditional anchorages,making the mini-implants being widely used in practical clinical therapies.In order to investigate how the loading condition and structural factors may affect the stability of mini-implants,we have established a three-dimensional finite element model to mimic a micro-screw implant anchoring in cortical bone and cancellous bone tissue under external loads.Be investigating the stress and deformation distribution for the implant with different lengths and loading condition,we have found that:external load vertical to the implant may induce largest deformation,corresponding to most unstable condition of the implant;increasing the anchorage length of micro-screw body can effectively reduce the maximum normal stress in the bone-implant interface,improving instability,however,such reduction effect becomes no longer significant when the length of implant anchorage is more than 11mm.

关 键 词：微种植体支抗 有限元分析 参数化设计 微种植体支抗长度 

分 类 号：R783.5[医药卫生—口腔医学]