Functional poly(ether-ketone-ketone) composite scaffold with enhanced cell-material interaction, anti-inflammatory and osteogenesis for facilitating osteointegration and bone regeneration

Bone defects resulting from trauma or disease remain a significant challenge in clinical practice, often requiring prolonged treatment. Poly(ether-ketone-ketone) (PEKK) is a commonly used implant material due to its excellent biocompatibility and mechanical properties, which are similar to those of bone. However, its biological inertness leads to poor anti-inflammatory and osteointegration properties, significantly hindering the bone repair process. In this study, a cryogel filled - PEKK/bioglass (BG) composite scaffold (SPBC) was prepared <i>via</i> 3D printing to provide immunomodulatory and bone integration performance. Compared with untreated PEKK, SPBC exhibited significant enhancements in surface properties, including higher hydrophilicity and roughness. Additionally, SPBC enhanced the adsorption of fibronectin and vitronectin on the scaffold surface and regulated the maturation of cytoskeleton and adhesion plaques by increasing the phosphorylation level of FAK at Y397, thereby promoting cell adhesion and spreading. Due to the release of bioactive ions, SPBC can significantly promote the polarization of RAW264.7 cells towards M2 and the secretion of anti-inflammatory cytokines, while also enhancing the proliferation and differentiation of rat mesenchymal stem cells (rMSCs) <i>in vitro</i>. Furthermore, the <i>in vivo</i> results confirmed the enhanced anti-inflammatory properties and the integration of SPBC with the host tissue. In summary, after surface modification and cryogel filling, SPBC demonstrated excellent anti-inflammatory and bone integration abilities, presenting potential for clinical application as an orthopedic implant scaffold.