Spark plasma sintering of an innovative bioactive glass containing therapeutic ions: Densification, controlled devitrification, mechanical properties and in vitro bioactivity

A novel Mg and Sr co-doped Bio_MS glass with a high crystallization activation energy (370 kJ/mol) was processed in this work by Spark Plasma Sintering (SPS) to achieve nearly fully dense samples. The material remains fully amorphous up to 800 °C, while higher temperatures lead to devitrification and the formation of glass-ceramics containing pseudowollastonite and wollastonite. The structural adaptability of the resulting products allows their biological and mechanical performance to be suitably tailored: lower SPS temperatures were found to maximize surface reactivity and accelerate HAp formation, whereas higher sintering temperatures improve hardness and Young’s modulus. Furthermore, SPS-processed Bio_MS ensures a controlled release of therapeutic Si, Ca, Mg, and Sr ions, making it an innovative solution for bone tissue engineering.