Injectable light-cured and bioabsorbable silk fibroin/hyaluronic acid (SF-HA) hydrogel tissue barrier for accelerating guided bone regeneration

In guided bone regeneration (GBR) surgery, a barrier membrane, commonly collagen material, is broadly used to prevent epithelial and fibroblast tissue from interfering with osteogenesis. However, collagen membranes usually fail to withstand the pressure from soft tissue collapse, leading to the severe collapse and displacement of bone graft materials, which ultimately results in inadequate bone augmentation. Besides, the collagen material cannot well prevent soft tissue adhesion. In this study, a novel light-cured, bioabsorbable hydrogel has been developed by co-assembling silk fibroin and hyaluronic acid without any small molecular crosslinkers, which can be directly injected into the bone-augmented region and quickly cured under UV light curing. The as-prepared hydrogel can be adhesive onto various irregular bone defect surfaces and provide a complete and continuous tissue barrier for bone graft materials. Among the hydrogels with different ratios of silk fibroin to hyaluronic acid, the one with a ratio of 1:3 (SF-HA-3) demonstrated the best mechanical performance, the lowest expansion rate, and a moderate degradation rate. In the animal models, the SF-HA-3 showed an excellent barrier effect and a stable space maintenance ability, accelerating obvious new bone formation, which was observed in the bone defect area.