POTENTIAL OF BIOACTIVE GLASS SCAFFOLDS AS IMPLANTS FOR STRUCTURAL BONE REPAIR

摘要

The repair of structural bone defects such as segmental defects in the long bones of the limbs is a challenging clinical problem. While many commercial osteogenic filler materials are suitable for repairing contained bone defects, no satisfactory biological solution to reconstituting segmental bone loss is yet available. Bioactive glass has attractive properties as a scaffold material for bone repair but there are concerns about its mechanical reliability in vivo. Recent advances have shown the ability to create porous scaffolds of silicate 13-93 glass with promising mechanical properties such as compressive strength and elastic modulus comparable to human cortical bone. Bone regeneration in osseous defects can be significantly enhanced by loading those strong porous 13-93 scaffolds with bone morphogenetic protein-2 (BMP2) prior to implantation. When implanted in critical-size segmental defects in rat femurs, as-fabricated scaffolds of 13-93 glass showed the capacity to support new bone infiltration and integration with host bone within 12 weeks. The release of metal ions from bioactive glass scaffolds could provide another approach for stimulating osteogenesis and angiogenesis in healing osseous defects. Recent advances in the mechanical and in vivo performance of 13-93 bioactive glass scaffolds are promising for the application of those scaffolds in structural bone repair.