Sol-gel derived vitroceramic materials for biomedical applications

Starting from SiO2–CaO–P2O5–ZnO–CaF2 oxide system, vitroceramic materials were obtained by employing the sol-gel approach, followed by thermal treatment in order to provide, in a controlled manner, the nucleation and growth of crystalline phases in the parent glassy matrix. Thermal analysis, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, selected area electron diffraction and Fourier transformed infrared spectroscopy were employed for the characterization of the resulting samples. The sintered vitroceramics present calcium silicates as crystallized nano-domains and a porosity that decreases with the enhancement of the processing temperature. The assessment of the biological properties was carried out in vitro by simulated body fluid immersion for 14 days, associated with a detailed analysis of the apatitic layer formed on the surface.