Formulation and characterization of glass-ceramics based on Na2Ca2Si3O9-Ca5(PO4)3F-Mg2SiO4-system in relation to their biological activity

Glasses having a chemical composition based on combeite [Na2Ca2Si3O9]-fluoroapatite [Ca-5(PO4)(3)F] and forsterite [Mg2SiO4] system were crystallized through controlled heat-treatment. Two forms of sodium calcium silicate e.g. combeite Na2Ca2Si3O9 and pectolite Na2CaSi3O8, were formed together with diopside (CaMgSi2O6) and monticellite (CaMgSiO4) in addition to fluoroapatite (Ca-5(PO4)(3)F) phases by thermal treatment of the glasses. Selected glass-ceramics were exposed to a simulated body fluid solution (SBF) which is close to human plasma for 3 weeks. Energy dispersive X-ray analysis (EDX) and inductive coupled plasma (ICP) analysis confirmed the formation of an apatite layer which indicate bioactivity in the all crystallized sample. A decreasing of surface bioactivity with increasing Mg2SiO4/Na2Ca2Si3O9 replacement was observed as indicated by the decrease in the amount of apatite layer on the surface of the crystallized specimens. The Vicker's microhardness of the studied glass-ceramic materials are between 5,047 and 6,781 MPa.