Effect of the solution flow rate on the in vitro bioactivity of 2.5CaO-2SiO2 glass

A comparative study of in vitro bioactivity of 2.5Ca0.2SiO2 glass has been carried out by soaking it in a simulated body fluid, with continuously and periodic exchange of this solution (dynamic and differential protocols). Dynamic assays were carried out at different solution flow rates, 3 mL/h, 6 mL/h, 12 mL/h, to study the influence of flow rate on glass reactivity. Glass surface was studied by Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive spectroscopy so as to compare the behavior in the two procedures, revealing that in both cases an apatite layer is formed on the glass surface, although there are differences on deposition rate and morphology, which are also influenced by the solution flow rate. (c) 2006 Wiley Periodicals, Inc.