In vitro and in vivo evaluation of non-crystalline calcium phosphate glass as a bone substitute

The purpose of this study was to evaluate the bone formability of calcium phosphate glass in vivo as well as in vitro. We prepared calcium phosphate glass in the system CaO-CaF2-P2O5-MgO-ZnO through the conventional melting process. Pre-osteoblastic MC3T3-E1 cells were cultured onto the calcium phosphate glass in alpha-MEM with beta-glycerophosphatase and ascorbic acid. Calcium phosphate glass particles were transplanted onto the critical-sized calvarial defects of Sprague-Dawley rats. The alkaline phosphatase activity in the experimental group was enhanced by the calcium phosphate glass significantly at 10-18 days after incubation than that of the control group (p<0.05). The promotion of bone-like tissue formation by the calcium phosphate glass was observed after 7 days and thereafter. In vivo test, new bone was formed in the upper side of the defects as well as the defect margin and dura mater. Experimental group always exhibited significantly higher values in the length, area and density of the newly formed bone than that of the control group (p<0.05). The results of the present study indicate that the prepared calcium phosphate glass affected osteogenesis by increasing collagen synthesis and calcification of the extracellular matrix in vitro and promoted new bone formation in the calvarial defects in the Sprague-Dawley rats.