Formation of hydroxyapatite onto glasses of the CaO–MgO–SiO2 system with B2O3, Na2O, CaF2 and P2O5 additives

New bioactive glasses with compositions based on the CaO–MgO–SiO2 system and additives of B2O3, P2O5, Na2O, and CaF2 were prepared. The in vitro mineralization behaviour was tested by immersion of powders or bulk glasses in simulated body fluid (SBF). Monitoring of ionic concentrations in SBF and scanning electron microscopy (SEM) observations at the surface of the glasses were conducted over immersion time. Raman and infrared (IR) spectroscopy shed light on the structural evolution occurring at the surface of the glasses that leads to formation of hydroxyapatite.