3D printed biomimetically hierarchical porous scaffolds from amorphous polyaryletherketone with nanohydroxyapatite for bone repair.

The repair of bone defects presents a complex challenge, requiring implants that satisfy anatomical, functional, and long-term stability demands. To address this need, polyaryletherketone (PAEK) has emerged as a promising customizable orthopedic material. However, its inherent bioinertness limits clinical application. Herein, inspired by the hierarchically porous architecture and composition of natural trabecular bone, amorphous polyaryletherketone (PAEK-N) scaffolds incorporating nanohydroxyapatite (nHA) for bone repair were developed via fused deposition modeling (FDM) 3D printing. Without the constraints of crystal lattices, PAEK-N can enhance the compatibility between the resin and nHA to maintain good stability of the composites. In vitro results reveal that nHA/PAEK-N implants possess favorable biocompatibility, biomineralization capacity, and protein adsorption ability which promote the adhesion, proliferation, and osteogenic activity of bone marrow mesenchymal stem cells (BMSCs). Furthermore, in vivo experiments demonstrate that the composites can enhance osseointegration and facilitate new bone ingrowth. This study establishes a promising PAEK-based implantable system with considerable potential for clinical bone repair applications.