通过骨支架的数字化建模分析其力学性能与内部流场分布

目的研究不同骨支架结构的力学性能与内部流场分布,为模型结构的优劣提供直观上的比较和评判,为骨支架结构设计提供有效的指导方法。方法利用Pro/Engineer和MIMICS等软件重建自然结构骨支架、编织状骨支架和球形孔骨支架,并通过有限元方法分析3种支架的有效弹性模量、应力分布和三维灌注培养下支架内部流场分布。结果采用相同材料设计得到的自然结构骨支架表现出更小的有效弹性模量;当3种支架受到相同压力时,自然结构骨支架内部应力峰值更小且应力分布更均匀;初始流速和流体黏度相同时,自然结构骨支架表现出更小的内部流速、壁面剪切应力和壁面压力。结论自然结构骨支架模型具有相对较好的生物力学性能,在3种骨支架中最适合用于骨组织工程中骨支架结构选型。

Analysis on mechanical properties and internal flow field distributions of bone scaffold by digital modeling

Objective To study mechanical properties of the bone scaffold with different structure and its internal flow field distributions, so as to provide a direct comparison and judgment on model structure and offer an effective guidance for bone scaffold structure design. Methods Bone scaffold with natural, woven and spherical pore structure were reconstructed respectively by using Pro/Engineer and Mimics. The effective elastic modulus for three kinds of scaffolds, as well as their stress distributions and internal flow field distributions under three dimensional perfusion culture system were analyzed with the finite element method. Results The bone scaffold with natural structure showed smaller effective elastic modulus, smaller peak stress and more uniform stress distributions under the same pressure. With the same initial velocity and fluid viscosity, the bone scaffold with natural structure showed smaller internal velocity, wall shear stress and wall pressure. Conclusions The bone scaffold with natural structure has better biomechanical properties, which corresponds to the design criteria of bone scaffold in bone tissue engineering.