• • 3.0% CB/BSA hydrogel achieved the highest bone volume fraction, bone mineral density, and trabecular thickness at 8 weeks (P<0.05), while reducing bone surface-to-volume ratio (P<0.05), indicating superior microarchitectural restoration compared to lower CB fractions and Bio-Oss® Collagen.
• • The 3.0% CB/BSA group upregulated WNT3A, β-catenin, VEGFA, COL1A1, PECAM-1, and OCN at both gene and protein levels (P<0.05), confirming Wnt/β-catenin pathway activation as the mechanistic driver of osteogenesis and angiogenesis.
• • No abnormalities in blood routine or serum liver/kidney function markers and no organ inflammation, necrosis, or fibrosis were observed, establishing a favorable in vivo safety profile for the photocrosslinked hydrogel.
• • The 3.0% CB/BSA formulation exhibited the best overall healing outcome, suggesting that its degradation kinetics—via hydroxyapatite dissolution and BSA network hydrolysis—are temporally matched to bone regeneration, though dynamic degradation monitoring remains necessary.