Wan Ying-ming, Bi Ming, Han Hui, Wang Jing-yun
Department of Prosthodontics, School of Stomatology, Jilin University, Changchun 130021, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2012 May;47(5):277-80. doi: 10.3760/cma.j.issn.1002-0098.2012.05.006.
To analyze the stress distribution in temporomandibular joint (TMJ) with different depth of curve of Spee (CS) by three-dimensional finite element model (3D-FEM).
FEM with different depth of CS were established. The depth was 2.50, 0 and 4.50 mm (model 0, 1, 2). The stress distribution were analyzed by software Abaqus. The change of stress were analyzed by paried t test.
The stress distribution patterns in TMJ with different depth of CS were similar. The Von Mises on the anterior surface of condyle and the Von Mises on the intermedial zone of the disc was higher. The S. Max. Principal of the condyle was mainly tensile stress. The S. Min. Principal of the condyle was mainly compressive stress. The S. Max. Principal of the disc was mainly tensile stress. The S.Min. Principal of the disc was mainly compressive stress.In model 0, the eviations of the Von Mises, the S.Max. Principal and the S.Min. Principal on the anterior surface of condyle were 0.1057 - 0.2298 MPa, -0.2243 - -0.3738 MPa and -0.3494 - -0.1165 MPa. The eviations of the Von Mises, the S.Max. Principal and the S. Min. Principal on the intermedial zone of the disc were 0.1099 - 0.6880 MPa, -0.3217 - 0 MPa and -1.2000 - -0.1000 MPa. The D-values of of Von Mises of condyle and disk between different models were extremely significant (P < 0.01).
With the same plane of occlusion, the stress distribution patterns of TMJ with different depth of CS is similar to that of normal occlusion. The final results also validate the anterior surface of condyle and intermediate zone of articular disc are the weight-bearing areas in TMJ. The changes of depth of CS change the value of the stress.
通过三维有限元模型(3D-FEM)分析不同Spee曲线深度(CS)时颞下颌关节(TMJ)的应力分布。
建立不同CS深度的有限元模型。深度分别为2.50、0和4.50mm(模型0、1、2)。采用Abaqus软件分析应力分布。采用配对t检验分析应力变化。
不同CS深度时TMJ的应力分布模式相似。髁突前表面的冯·米塞斯应力和盘中间带的冯·米塞斯应力较高。髁突的最大主应力主要为拉应力。髁突的最小主应力主要为压应力。盘的最大主应力主要为拉应力。盘的最小主应力主要为压应力。在模型0中,髁突前表面的冯·米塞斯应力、最大主应力和最小主应力的偏差分别为0.1057 - 0.2298MPa、-0.2243 - -0.3738MPa和-0.3494 - -0.1165MPa。盘中间带的冯·米塞斯应力、最大主应力和最小主应力的偏差分别为0.1099 - 0.6880MPa、-0.3217 - 0MPa和-1.2000 - -0.1000MPa。不同模型间髁突和盘的冯·米塞斯应力的D值差异极显著(P < 0.01)。
在相同咬合平面下,不同CS深度时TMJ的应力分布模式与正常咬合时相似。最终结果也证实髁突前表面和关节盘中间带是TMJ的负重区。CS深度的变化会改变应力值。