摘要
目的:用有限元方法分析3种不同施力方式远移上颌第一磨牙时牙周膜应力分布。方法:应用薄层CT技术及ANSYS8.0有限元软件建立上颌第一磨牙、牙周膜、牙槽骨的有限元模型。全部采用8节点的六面体单元,包括15 747个节点,67 401个单元。在ANSYA8.0有限元软件中分别对其进行3种不同方式的加载和计算。结果:不同的加载方式所产生的牙周膜应力分布不同。当牙冠颊侧施加200 g远中向力时,牙周膜远中颈部及腭侧根出现压力集中区。牙周膜的最小应力为0.031359 Pa,远中颈部最大应力为0.9854 Pa。当牙冠腭侧施加200 g远中向水平力时,牙周膜远中颈部及颊侧出现压应力集中区。牙周膜的最小应力为0.033099 Pa,远中颈部最大应力为1.144 Pa。当牙冠颊侧、腭侧同时各施加100 g远中向水平力时,牙周膜远中颈部中部出现压力集中区。牙周膜的最小应力为0.031367 Pa,远中颈部最大应力为0.783538 Pa。结论:远移磨牙时,单侧给予单纯水平力时,会出现牙齿的旋转和远中倾斜,当颊舌向同时加载水平向力时,可以克服牙齿的旋转趋势。
Objective： To analyse the distribution of periodontial memberane stress of the upper first molar distalized by three different orthodontic forces using 3 - D finite element model. Methods： The advanced CT scanning and finite element software ANSYS8.0 were used to establishe the upper first molar model, including tooth, alveolar bone and periodontal membrane. The model of the upper first molar consisted of 15747 nodes and 67401 isoparametric eight - node elements. Then three different loading patterns were added to the model. Results： The stress pattern in the periodontal membrane for a buccal distalizing force （F =200g） showed high concentration at the distal cervical level and the palatal root. The stress pattern in the periodontal membrane for a palatal distaling force （F = 200g） showed high concentration at the distal cervical level and buccal side . The stress pattern in the periodontal membrane for exerting distalizing force （ F = 100g） from both sides simultaneously showed high concentration at distal cervical level of the tooth. Conclusion： The unilateral distalizing force will cause molar rotation and distal tipping, while the bilateral distalizing force can avoid its rotation trend.
出处
《口腔医学研究》
CAS
CSCD
2006年第2期166-168,共3页
Journal of Oral Science Research
关键词
上颌第一磨牙
生物力学
有限元法
Maxillary first molar Biomechanics Finite element method
