Calcium-phosphate-silicate Composite Bone Cement: Self-setting Properties And In Vitro Bioactivity

摘要

In this study, a novel low temperature setting calcium phosphate-silicate cement was obtained by mixing CaHPO_4 · 2H_2O (DCPD) and Ca_3SiO_5 (C_3S) with 0.75 M sodium phosphate buffers (pH = 7.0) as liquid phase. The self-setting properties of the obtained DCPD/C_3S paste with liquid to powder ratio (L/P) of 0.6 ml/g, such as setting times, injectability, degradability and compressive strength were investigated and compared with that of DCPD/CaO cement system. The results indicated that, with the weight ratio of C_3S varied from 20% to 40%, the workable DCPD/C_3S pastes could set within 20 min, and the hydrated cement showed significantly higher compressive strength (around 34.0 MPa after 24 h) than that of the DCPD/CaO cement system (approximately 10.0 MPa). Furthermore, the in vitro pH value of the cements was investigated by soaking in simulated body fluid (SBF) for 12 h, and the result indicated that the DCPD/C_3S did not induce significant increase or decrease of pH value in SBF. Additionally, the composite cement possesses better ability to support and stimulate cell proliferation than the DCPD/ CaO cement. With good hydraulic properties, improved biocompatibility and moderate degradability, the novel DCPD/C_3S bone cement may be a potential candidate as bone substitute.