Characterization of 3D-printed gelatin/sodium alginate/58S bioactive glass scaffold and osteogenesis in rabbit...

Critical-sized maxillofacial bone defects often lead to delayed healing or non-union, necessitating clinical intervention with osteoconductive biomaterials. 58 S bioactive glass (BG) is a promising candidate to release osteogenic ions (Si, Ca, P). In the present study, a dual-network scaffold was fabricated via 3D printing using a bioink composed of gelatin (Gel), sodium alginate (SA), and 58 S BG (mass ratio 10:4:7). The scaffold's physicochemical properties, biocompatibility, and osteogenic efficacy were systematically evaluated. The scaffold demonstrated favorable structural characteristics with a high porosity of 76 ± 1% and a compressive Young's modulus of 166.3 ± 1.6 kPa. It exhibited a volumetric swelling ratio of 8.57 ± 1.31% and maintained 62% of its initial mass after 14 weeks in simulated body fluid (SBF), indicating excellent stability and controlled degradation. Subcutaneous implantation in nude mice revealed no signs of inflammation or fibrous encapsulation at 4 and 8 weeks, confirming its excellent biocompatibility. In a critical-sized rabbit calvarial defect model, Micro-CT analysis after 6 months showed that the scaffold group achieved a bone volume fraction (BV/TV) of 46.8 ± 1.2%. This result was comparable to the Bio-Oss (48.7 ± 3.1%), with no residual scaffold particles observed, confirming its complete biodegradation synchronized with new bone formation. In conclusion, this biodegradable Gel/SA/58 S BG scaffold combines favorable printability, structural stability, high bioactivity, and well-matched degradation kinetics, presenting a highly promising and translatable platform for the personalized reconstruction of maxillofacial bone defects.