Fouad H, AlFotawi Randa, Alothman Othman Y, Alshammari Basheer A, Alfayez Musaad, Hashem Mohamed, Mahmood Amer
Applied Medical Science Department, Community College, King Saud University, Riyadh 11437, Saudi Arabia.
Department of Biomedical Engineering, Faculty of Engineering, Helwan University, Helwan 11792, Egypt.
Materials (Basel). 2018 Mar 29;11(4):521. doi: 10.3390/ma11040521.
In this study, porous polyethylene scaffolds were examined as bone substitutes in vitro and in vivo in critical-sized calvarial bone defects in transgenic Sprague-Dawley rats. A microscopic examination revealed that the pores appeared to be interconnected across the material, making them suitable for cell growth. The creep recovery behavior of porous polyethylene at different loads indicated that the creep strain had two main portions. In both portions, strain increased with increased applied load and temperature. In terms of the thermographic behavior of the material, remarkable changes in melting temperature and heat fusion were revealed with increased the heating rates. The tensile strength results showed that the material was sensitive to the strain rate and that there was adequate mechanical strength to support cell growth. The in vitro cell culture results showed that human bone marrow mesenchymal stem cells attached to the porous polyethylene scaffold. Calcium sulfate-hydroxyapatite (CS-HA) coating of the scaffold not only improved attachment but also increased the proliferation of human bone marrow mesenchymal stem cells. In vivo, histological analysis showed that the study groups had active bone remodeling at the border of the defect. Bone regeneration at the border was also evident, which confirmed that the polyethylene acted as an osteoconductive bone graft. Furthermore, bone formation inside the pores of the coated polyethylene was also noted, which would enhance the process of osteointegration.
在本研究中，对多孔聚乙烯支架作为转基因斯普拉格-道利大鼠临界尺寸颅骨缺损的骨替代物进行了体外和体内研究。显微镜检查显示，材料中的孔隙似乎相互连通，使其适合细胞生长。多孔聚乙烯在不同载荷下的蠕变恢复行为表明，蠕变应变有两个主要部分。在这两个部分中，应变均随施加载荷和温度的增加而增加。就材料的热成像行为而言，随着加热速率的增加，熔点和热熔出现了显著变化。拉伸强度结果表明，该材料对应变速率敏感，且具有足够的机械强度来支持细胞生长。体外细胞培养结果显示，人骨髓间充质干细胞附着在多孔聚乙烯支架上。支架的硫酸钙-羟基磷灰石（CS-HA）涂层不仅改善了细胞附着，还增加了人骨髓间充质干细胞的增殖。在体内，组织学分析表明，研究组在缺损边缘有活跃的骨重塑。缺损边缘的骨再生也很明显，这证实了聚乙烯起到了骨传导性骨移植的作用。此外，还观察到涂层聚乙烯孔隙内有骨形成，这将增强骨整合过程。
