Preparation and in vitro bioactivity of novel merwinite ceramic.

The ceramic of merwinite (Ca3MgSi2O8) was prepared by sintering sol-gel-derived merwinite powder compacts. The mechanical properties and the coefficient of thermal expansion (CTE) of the merwinite ceramic were determined. In vitro bioactivity of the merwinite ceramics was evaluated. Our results showed that the sintered body was single-phase merwinite ceramic, and that its bending strength, fracture toughness and Young's modulus were approximately 151 MPa, 1.72 MPa m(1/2) and 31 GPa, respectively. The CTE of the ceramic was 9.87 x 10(-6) degrees C(-1) and close to that for the Ti-6Al-4V alloy (9.80 x 10(-6) degrees C(-1)). Immersion of the sintered body in simulated body fluid induced surface precipitation of Ca-P rich layers. Cell culture experiment results confirmed that soluble ionic products from merwinite dissolution significantly stimulated osteoblast proliferation, and osteoblasts adhered and spread well on merwinite ceramic surfaces.