Bioglass dissolution: a comparison between SBF solution and hydrolytic etching

The evaluation of chemical dissolution phenomena of the glasses in general is important because it is related to the bioactivity. This paper aims a comparative study of the bioglass dissolution between in vitro bioactivity test in SBF (Simulated Body Fluid) solution and the chemical durability test, in glasses on SiO₂-Na₂O-CaO with 6wt% de P₂O₅ system. The glasses were obtained by melting at 1500°C/2h and annealed at 500°C/2h followed by natural cooling. To in vitro test, the samples were immersed in SBF solution in different periods (1, 3, 7 and 14 days) at 7,25 pH and 37 deg C. For the hydrolytic resistance test were performed in a Soxhlet column. The physic-chemical and morphological characterization of the samples before and after both tests was realized through XRD, DRIFT and SEM. The samples presented a difference in kinetics dissolution for both tests that allow an improved understanding of the glasses bioactivity mechanism. (author)