摘要
贯通性是骨组织工程支架的重要参数,决定包含蛋白和细胞的体液渗入和组织生长。本研究采用Micro-CT技术对三种不同工艺(球粒堆积、蜡球造孔、纤维堆积)构建的羟基磷灰石多孔支架进行断层扫描,并从三方面研究支架的贯通性:(1)通过影像重建定量分析支架孔隙的三维贯通结构;(2)统计分析比较三种支架在贯流方向上的孔隙率变化;(3)有限元模拟支架的内部液流分布情况。结果表明,球粒堆积支架与蜡球造孔支架孔隙率分布较均匀,而纤维堆积支架孔隙分布较杂乱。液流模拟(流速分布)发现,球粒堆积支架与蜡球造孔支架中液体流动均匀,但是蜡球造孔支架孔壁近表面区域存在大量"漩涡流",不利于支架内细胞与液流之间的物质交换,该结果有可能解释球粒堆积支架体内成骨性优于蜡球造孔支架的动物体内实验结果。
Pore interconnectivity is a key parameter for bone tissue engineering scaffolds, which controls penetration of body fluid with proteins and cells, and tissue ingrowth. The present study investigated the porous characteristics of hydroxyapatite （HA） scaffolds prepared via three processes （HA sphere packing, wax sphere-leaching and HA fiber aggregation） by micro-computed tomography （gCT） from following three procedures： （1） modeling of the porous structure by image reconstruction; （2） analysis of porosity along longitudinal direction; and （3） simulation of fluid flow across the scaffold by finite element analysis （FEA）. Image analyses revealed that, the scaffolds prepared by the above two methods featured relatively regular porosity distributions, whereas that by HA fiber aggregation had an irregular distribution. Fluid velocity distribution by FEA suggested that scaffolds prepared by HA sphere packing and wax sphere leaching readily allowed penetration of fluid due to their favorable pore interconnectivity. The fluid velocity vector distribution predicted that circular flows dominated near the pore wall in the scaffold prepared by wax sphere leaching. These circular flows may impede the material exchange between cells attached to the pore wall and the body fluid, which may illustrate that the inferior in viw） osteogenic activity of scaffolds prepared by wax sphere leaching when compared with those produced by HA sphere packing.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第1期71-76,共6页
Journal of Inorganic Materials
基金
国家重点基础研究发展计划(973计划
2012CB933600)
国家自然科学基金(51172188)
四川省科技支撑计划(2010FZ0048)~~
关键词
组织工程支架
结构图像重建
孔隙贯通性
计算机建模
流速分布
tissue engineering scaffolds
structure image reconstruction
interconnectivity
computer modeling
fluid velocity distribution
