3D-Printed Bone Scaffolds Promote Bone Regeneration Through a Multi-Stage Temporal Therapeutic Strategy

Bone defect repair is a complex process governed by intricate and well-coordinated temporal regulatory mechanisms. Conventional bone scaffolds are frequently proved underperformance due to their inability to adapt to these spatio-temporal demands. In this study, we developed a 3D-printed composite bone scaffold using ordered hexagonal mesoporous silica nanoparticles (SBA-15) loaded with Akebia saponin D (ASD) and polylactic acid (PLLA) through selective laser sintering (SLS). The outcomes revealed that the scaffold possessed a favorable porous structure, degradability, and the capability of slow drug release. Simultaneously, the scaffold exhibited minimal cytotoxicity and high cell adhesion. Significantly, the scaffold demonstrated the capacity to orchestrate macrophage polarization to reduce inflammation in the early phase of bone repair, enhance osteogenesis in the intermediate phase, and impede osteoclast activity in the final stages. These properties are instrumental in promoting effective bone healing. This study introduces a novel 3D-printed composite bone scaffold system capable of temporally regulating bone healing, offering a promising approach for treating bone defects.