螺距对微植体即刻加载稳定性影响的数值研究

Numerical study on the stability of micro-implant with different pitchs for immediate loading

目的研究口腔正畸微植入支抗螺距对骨界面稳定性的影响。方法采用三维有限元方法,分别研究了四种螺距(0.3mm、0.5mm、0.7mm和1.0mm)微植体在1.47N横向荷载作用下的微植体-骨界面位移和应力分布。结果螺距对微植体表面应力分布的影响显著,最大应力值随螺距的减小而减小,而且螺距对颈部和中部位置应力分布的影响不同;随着螺距增大,在颌骨上的位移增大趋势显著,但螺距对微植体位移分布的影响并不显著。结论在即可加载条件下,建议临床使用螺距为0.5-0.7mm的微植体作为正畸支抗。

Objective To study the stability of micro-implant orthodontic anchorage （MIA） with different pitch in the case of immediate loading. Method Employing 3D finite element analysis method, the stress and displacement distribution on the bone interface of MIA with different pitch （0.3 mm,0.5 mm,0.7 mm and 1.0 mm, respectively）, which was 1.47 N loaded vertically in the major axis direction, were analyzed. Result The pitch affected the stress distribution significantly, because the maximum stress increased with the pitch decreasing and the impact of pitch on stress distribution on neck and central locations of MIA were different; to decrease the pitch could reduce the max displacement of the jaw, but the impact of pitch on displacement distribution of MIAwas not significant. Conclusions In the case of immediate loading, MIA with pitch 0.5 mm - 0.7 mm is suggested to be selected as orthodontic anchorage in the clinic.