Shape-Memory Collagen/Silk-Fibroin Scaffold for Dura Sealing and Skull Base Regeneration

When a skull base defect occurs, reconstruction is typically performed using a variety of autologous grafts, flaps, or synthetic materials. Failure to achieve appropriate management and closure can lead to serious consequences, such as cerebrospinal fluid (CSF) leakage and subsequent meningitis. Current grafts and synthetic patches often lack biological activity, mechanical integration, and sealing capacity. Here, we developed a multifunctional, injectable composite scaffold composed of collagen/silk-fibroin (S-F) and α-tricalcium phosphate (α-TCP), designed for simultaneous CSF sealing and tissue regeneration. The upper S-F-rich layer forms a dense, non-porous barrier to prevent CSF egress, while the lower α-TCP-containing layer promotes osteointegration and mechanical support. The scaffold is fabricated via a cryogelation-inspired process, enabling shape-memory behavior for minimally invasive deployment. In vitro studies confirmed favorable cell adhesion, matrix protein expression, and osteogenic activation. In vivo evaluation further indicated stable integration of the composite at the implantation site without severe adverse tissue responses. Overall, these results support the potential of this layered, shape-memory composite as a dual-functional platform for cranial base reconstruction.