Bioceramics and bioglass ceramics are a wide arena of research in the current era due to their potential applications in orthopedics and surgery. Although there is a great strategic significance of glass-ceramics in the field of bio-materials yet there is a lack of detailed study on the correlation between the structure and the activity of glass composition in biological surroundings that negatively affect the further progress in improving the chemical stability and modifying the biodegradability of these materials for certain applications. So there is a need to prepare and characterize new bio-glass ceramic materials using every possible compositional and parametric changes because bio-activity and structural properties of glass-ceramics are found to be greatly affected by these important variations. In this book, synthesis of bio-glass ceramics of novel compositions with different CaO/MgO ratio have been discussed and following features are explained in detail. 1- Correlation between crystalline phases, microstructure, and mechanical strength of bio-active glass ceramics with different CaO/MgO ratios. 2- Dissolution behaviour of bio-active glass ceramics with different CaO/MgO