Physicochemical and biological properties of composite bone cement based on octacalcium phosphate and tricalcium silicate

Abstract

Biocompatible tricalcium silicate (C3S) bone cement is widely used as dental and bone repair material; however, its long setting time, poor injectability and low initial mechanical properties limit clinical applications. In order to improve C3S silicate bone cement and its derivatives to play a more important role in tooth restoration, bone defect repair, implant coating and tissue engineering scaffolds, a novel C3S and octacalcium phosphate (OCP) composite bone cement (OCP/C3S) was prepared and evaluated for setting time, injectability, anti-flocculation, pH, microstructure, bioactivity and cytotoxicity. The setting time of the OCP/C3S composite bone cement was controlled within the clinically operable time range (8.3–13.7 min); the cement exhibited good compressive strength, injectability (93.54%), and anti-collapse performance. The 20% OCP/C3S composite bone cement had a compressive strength of 28.94 MPa, 93% stronger than pure C3S (14.98 MPa). An in vitro immersion test showed that the composite bone cement had excellent hydroxyapatite forming ability, proper degradation rate, and a low pH value. Cellular experiments confirmed the low cytotoxicity of the composite bone cement and its great capacity for cell proliferation. These results indicate that 20% OCP/C3S composite bone cement is a promising biomaterial.