不同降解周期下Ⅱ型胶原-丝素蛋白复合软骨支架的应力松弛行为  

Stress Relaxation Behavior of Collagen Type II-Silk Fibroin Composite Cartilage Scaffold under Different Degradation Cycles

作　　者：宋智云 高丽兰[1,2,3] 魏莹 谭沿松 李瑞欣 张春秋 SONG Zhiyun;GAO Lilan;WEI Ying;TAN Yansong;LI Ruixin;ZHANG Chunqiu(Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control,Tianjin University of Technology,Tianjin 300384,China;National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology),Tianjin 300384,China;Tianjin Enterprise Key Laboratory on Hyaluronic Acid Application Research,Tianjin 300457,China;Central Laboratory,Tianjin Stomatological Hospital,Tianjin 300041,China)

机构地区：[1]天津理工大学天津市先进机电系统设计与智能控制重点实验室,天津300384 [2]机电工程国家级实验教学示范中心(天津理工大学),天津300384 [3]天津市透明质酸应用研究企业重点实验室,天津300457 [4]天津市口腔医院中心实验室,天津300041

出　　处：《医用生物力学》2023年第2期331-337,共7页Journal of Medical Biomechanics

基　　金：国家自然科学基金项目(32271371,12072235,11972198);天津市自然科学多元投入基金项目(21JCZDJC00920,21JCYBJC00940)。

摘　　要：目的利用有限元分析与理论模型相结合的方法,研究软骨支架在不同降解周期下的应力松弛行为。方法基于已建立的降解本构模型计算不同降解周期下支架弹性模量;建立软骨支架有限元模型,并进行应力松弛仿真,分析支架松弛应力随时间的变化。建立应力松弛本构模型,对支架力学性能进行预测。结果软骨支架降解14、28、42、56 d时,弹性模量分别为32.35、31.12、29.91、28.74 kPa。软骨支架各层的应力分布表现为上层受力最大;支架整体松弛应力随着时间增加先快速下降,然后趋于平稳;降解56 d时,支架能承受的应力仍在软骨的生理载荷范围内。应力松弛本构模型预测结果与有限元模拟结果吻合较好。结论随降解时间的增加,支架弹性模量逐渐减小。降解时间越长,支架能承受的应力越小。相同降解时间下,施加的压缩应变越大,支架受力越大。有限元仿真和应力松弛本构模型可以有效预测支架降解时的应力变化。Objective To study stress relaxation behaviors of cartilage scaffolds under different degradation cycles by using finite element analysis combined with theoretical models.Methods Based on the established degradation theoretical model,the elastic modulus of the scaffold was calculated under different degradation cycles.The finite element model of cartilage scaffolds was established and stress relaxation simulation was performed to analyze the variation of scaffold relaxation stress with time.The stress relaxation constitutive model was established to predict mechanical properties of the scaffold.Results The elastic modulus of cartilage scaffolds at 14th,28th,42nd,56th day after degradation was 32.35,31.12,29.91,28.74 kPa,respectively.The upper layer for cartilage scaffolds was the largest.The overall relaxation stress of the scaffold decreased rapidly with time and then tended to be stable.At 8th week after degradation,the stress which the scaffold could withstand was still within the physiological load range of the cartilage.The predicted results of the stress relaxation constitutive model were in good agreement with the finite element simulation results.Conclusions The elastic modulus of the scaffold gradually decreases with the increase of degradation time.The longer the degradation period is,the less stress the scaffold can withstand.At the same degradation period,the larger the applied compressive strain,the larger the stress on the scaffold.Both the finite element simulation and stress relaxation constitutive model can effectively predict stress variations of cartilage scaffolds under degradation.

关 键 词：软骨支架 体外降解 应力松弛 本构模型 有限元分析 

分 类 号：R318.01[医药卫生—生物医学工程]