Effects of Micro/Nano-Sized Natural Calcium Phosphate Cements on Behaviors of Alveolar Bone Marrow Stem Cells

摘要

Calcium phosphate cements (CPCs) are used as a promising graft substitutes for bone tissue engineering. Not only their surface topography but also mechanical strength and osteoinductivity can be influenced by composition ratio of micro/nano-sized calcium phosphate powders (m/nCPPs) in CPCs. In this study, we fabricated CPCs according to various ratios of m/nCPPs and examined to verify their potentials as implanting materials for alveolar bone defects (ABDs). In morphological analysis higher ratio ofmCPPs caused more rough and porous surface property. In XRD analysis there were little changes between CPCs, in other words, chemical properties among CPCs were almost similar. Elastic moduli of CPCs increased with the increase of nCPPs ratio, except forthe CPCs consisting of 100% nCPPs. Cell adhesion and viability were investigated on the surfaces of CPCs, using alveolar bone marrow stem cells (ABMSCs), with respect to the various ratios of m/nCPPs. The more nCPPs were incorporated in CPCs, the lower cell adhesion and viability were. Cell morphology observed by scanning electron microscopy and immunocytochemistry showed that ABMSCs' size was getting smaller as ratio of nCPPs increased. Interestingly, although there was no significant difference, alkaline phosphatase assay showed that CPCs of which composition ratio was 50:50 showed the highest osteoinductivity. Conclusively, because CPCs of which the micro.nano CPPs was 50:50 not only showed enough mechanical strength, cell adhesion but also showed the highest cell viability and osteoinductivity, it would be the most suitable CPCs as a bone graft substitute for ABDs.