Material properties of living soft tissue composites.
Material properties of living soft tissue composites.
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活体软组织复合材料的材料特性。
DOI：
10.1002/jbm.820221409
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Berg,RA
中科院分区：
文献类型：
--
作者：
Jain,MK;Chernomorsky,A;Silver,FH;Berg,RA
接种成纤维细胞的胶原海绵已被用作伤口愈合应用中的软组织替代品。这种生物材料是结缔组织的良好体外类似物。因此，对该材料特性的分析可能有助于软组织的理论建模。测量这种细胞接种的胶原海绵的应力-应变曲线，以确定复合材料的刚度和极限拉伸强度。理论建模是通过使用复合球模型定义粒子增强矩阵来完成的。然后将单轴取向纤维系统引入到该等效均匀介质中，并使用复合圆柱体模型确定材料特性。进行几何平均以获得具有随机取向纤维的复合材料的刚度和泊松比。模型的输入是成分材料特性、细胞体积分数和纤维体积分数。从理论结果来看，软组织及其替代品的材料性能取决于纤维机械性能和体积分数，而不是细胞机械性能和体积分数。因此，实验观察到的复合材料刚度随着细胞数量的增加而增加，这是由于新合成的更硬的胶原纤维的沉积，而不是由于细胞本身的物理存在。
Collagen sponges seeded with fibroblasts have been used as a soft tissue substitute in wound healing applications. This biomaterial is a goodin vitroanalog of a connective tissue. Therefore, analysis of the properties of this material may be useful for theoretically modeling soft tissues. Stress–strain curves for such cell‐seeded collagen sponges were measured to determine composite stiffness and ultimate tensile strength. Theoretical modeling was done by defining a particle‐reinforced matrix using the composite sphere model. A system of uniaxially oriented fibers was then introduced to this equivalent homogeneous media and material properties were determined using the composite cylinder model. Geometric averaging was performed to yield the stiffness and Poissons' ratio for a composite with randomly oriented fibers. Inputs to the model were constituent material properties, cell volume fraction, and fiber volume fraction. From theoretical results, material properties of soft tissues and their substitutes depend on fiber mechanical properties and volume fraction and not cellular mechanical properties and volume fraction. Therefore, the increase in experimentally observed composite stiffness with increased cell number was due to deposition of newly synthesized stiffer collagen fibers, and not due to the physical presence of cells themselves.