In this work we develop a mathematical model, based on a system of reaction-diffusion equations, to analyse the dissolution and bioactivity for a bio-glass. The development of porous bioactive glasses is part of a multidisciplinary task. This family of substitutes is particularly adapted to regenerative medicine and suitable for many applications such as prolonged-release drugs. For example in pharmacology, the development of bioactive systems have shown that the release of drugs from the synthesized porous bio-glasses is controlled by a diffusion mechanism, such as a dissolution-precipitation process, due to the porosity criteria. Here we first show the well-posedness of the derived mathematical model, then we propose a numerical framework using a finite volume scheme to show useful results in real applications. 2020 Subject Classification. Primary 97M10, 97M60; Secondary 65L60, 65N12.