Study on the self-setting property and the in vitro bioactivity of β-Ca2SiO4

This study sought to investigate the physical and chemical properties of beta-dicalcium silicate (beta-Ca2SiO4) in order to evaluate its use as an injectable bioactive cement filler. Workable beta-Ca2SiO4 pastes with a liquid-to-powder (LIP) ratio of 1.0-1.2 could be injected for 10-30 min (nozzle diameter 2.0 mm) and enabled initial setting times of 60-180 min. The setting process yielded cellular structures with compressive strengths of 4.8-28.8 MPa after 2-28 days. The paste was soaked in simulated body fluid (SBF), and the results demonstrated that it exhibited a moderate degradation and could induce carbonated hydroxyapatite formation. The ionic products of the paste dissolution enhanced a proliferative response of fibroblasts compared with the cells cultured alone, and this cement could also support adhesion and spreading of the mesenchymal stem cells. Finally, with the use of gentamicin as a model drug, it was found that a high dose of drug release from the paste was maintained for 14 days, and there was a sustained release over 4 weeks. This combination of properties indicates that the novel beta-Ca2SiO4 cement might be suitable for potential applications in the biomedical field, preferentially as materials for bone/dental repair and controlled drug-delivery systems. (c) 2005 Wiley Periodicals, Inc.