Three-dimensional Glass-derived Scaffolds for Bone Tissue Engineering: Current Trends and Forecasts for the Future

Biomaterials used in regenerative medicine are often designed to act as 3D porous templates (scaffolds) able to support and promote the growth and repair of natural tissues. Some types of glasses have a great potential for making bone tissue engineering scaffolds, as they can bond to host bone, stimulate bone cells toward osteogenesis, and resorb at the same time as the bone is repaired. This review article highlights the evolution of glass-based scaffolds for bone tissue engineering; specifically, the features, limitations, and advantages of the different types of glass-derived scaffolds proposed in the literature (macroporous glass-ceramic, sol-gel glass, composite, graded, hybrid, and hierarchical implants) are critically examined, discussed, and compared. Future directions for the research are also suggested, highlighting the promise of multifunctional systems able to combine bone regeneration and drug release abilities, the increasing role of nondestructive advanced imaging techniques, such as X-ray microtomography, for scaffolds investigation and the potential of stem cells incorporation into scaffolds.