The importance of Mg in the human body, its key role in bone tissue development, in addition to its application to improve and modify physical, thermal, and mechanical properties of bioactive silicate glasses, make Mg a very interesting element as a component of bioactive glasses for medial applications. Although Mg is a typical element in the composition of numerous developed bioactive glasses, the analysis of the literature reveals that further research is required to gain comprehensive understanding about the effects of MgO on bioactive glass structure and properties. This article presents a comprehensive overview of the field of Mg-containing bioactive glasses discussing available compositions and summarising existing knowledge on effects of MgO on glass properties. The biomedical applications of several developed glasses are discussed highlighting the distinct effects of Mg in relevant areas, such as bioactivity and cell response, and focusing on the most common applications for these glasses, such as bone cements, bioactive coatings, and scaffolds for bone tissue engineering. The effect of Mg on bone development is discussed and avenues for future research in the field are proposed, emphasizing the need to investigate unstudied properties of (already developed) Mg-containing glass compositions, such as angiogenesis-stimulating action and the effect on osteoclast functions, to develop new Mg-containing bioactive glasses as well as to make products of different shape designs such as nanoparticles, fibres and complex porous structures.
