Study on physicochemical properties and in vitro bioactivity of tricalcium silicate–calcium carbonate composite bone cement

In this article, a novel bone cement composed of tricalcium silicate (Ca3SiO5; C3S) and calcium carbonate (CaCO3) was prepared with the weight percent of CaCO3 in the range of 0, 10, 20, 30, and 40%. The initial setting time was dramatically reduced from 90 to 45 min as the content of CaCO3 increased from 0 to 40%, and the workable paste with a liquid/powder (L/P) ratio of 0.8 ml/g could be injected between 2 and 20 min (nozzle diameter 2.0 mm). The composite cement showed higher mechanical strength (24–27 MPa) than that of the pure Ca3SiO5 paste (14–16 MPa). Furthermore, the composite cement could induce apatite formation and degrade in the phosphate buffered saline. The results indicated that the Ca3SiO5–CaCO3 paste had better hydraulic properties than pure Ca3SiO5 paste, and also the composite cement was bioactive and degradable. The novel bone cement could be a potential candidate as a bone substitute.