摘要
目的通过三维有限元方法探讨转矩对不同直径与长度的微螺钉种植体初期稳定性的影响，为正畸临床提供参考。方法建立96个上颌骨实体模型，并建立直径分别为1．2、1．6、2．0mm，长度分别为6、8、10、12mm共12种尺寸的微螺钉种植体实体模型，将每种尺寸的种植体分别与8个上颌骨模型结合，并用随机数表法随机选出4个加载1．96N水平力（水平力组），另外4个加载6N·mm转矩和1．96N水平力（复合作用组），分析两组种植体位移峰值的区别，以及两种加载条件下直径和长度对种植体位移峰值的影响。结果种植体长度不改变加载条件对位移峰值的影响，但种植体直径与加载条件间有相互作用，种植体直径为1．2、1．6、2．0mm时水平力组种植体位移峰值[分别为（7．71±0．49）、（3．94±0．31）、（2．32±0．43）μm]均显著低于复合作用组[分别为（9．22±0．63）、（4．62．4-0．52）、（2．69±0．49）灿m]（P〈0．05）。种植体直径为1．2mm时的两组位移峰值差值[（1．61士0．22）μm]显著大于直径为1．6、2．0mm时的两组位移峰值差值[（0．64±0．12）、（0．49±0．06）μm]（P〈0．05）。结论水平力复合转矩对种植体初期稳定性存在不利影响，对种植体同时施加转矩和水平力时应使用直径大于1．2mm的种植体。
Objective To investigate the influence of the diameter and length of the mini-implant on the primary stability after loading with composite forces （CF） which contained torque and horizontal forces （HF）. Methods Ninety-six finite element models were established by the combination of mini-implant and bone, diameters （1.2 ram, 1.6 mm, 2. 0 mm ） and length （ 6 ram, 8 mm, 10 ram, 12 mm）. There were 12 sizes, each size corresponded with 8 models. Group HF （ each size n = 4） was loaded with 1.96 N horizontal force and Group CF （ each size n = 4） was loaded with composite force which contained 6 N mm torque and 1.96 N horizontal force. The maximum displacement of mini-implant with different force directions, implant diameters and lengths were evaluated. Results The effect of force direction on the displacement related to diameter of mini-implant. The maximum displacement under load with HF respectively was changed with the changing of diameter[ 1.2 mm： （7.71 ±0. 49） μm; 1.6 ram： （3.94 ±0. 31 ） μm; 2.0 mm： （2. 32 ±0. 43 ） μm], which were smaller than the maximum displacement of Group CF[1.2mm： （9.22±0.63） μm; 1.6 mm：（4.62±0.52） μm; 2.0 mm： （2.69 ±0.49） μm ]（P〈 0. 05）. When diameter was 1.2 mm, the difference of the maximum displacement[ （ 1.61 ± 0. 22） μm] between Group HF and CF was more obvious than that when the diameter was 1.6 mm or 2. 0 mm[ （0. 64±0. 12）, （0. 49 ±0. 06） μm ] （P 〈 0. 05）. Conclusions The composite force had unfavorable effect on the primary stability of the mini-implant. The diameter of the mini-implant had better be larger than 1.2 mm when the composite forces were applied.
出处
《中华口腔医学杂志》
CAS
CSCD
北大核心
2013年第1期37-40,共4页
Chinese Journal of Stomatology
关键词
转矩
有限元分析
正畸支抗
微螺钉种植体
Torque
Finite element analysis
Orthodontic anchorage procedures
Mini-screw
