Channel triangle-pillar scaffold incorporated manuka oil triketone to enhance bone regeneration

The development of scaffolds with optimised architecture and bioactive components is critical for enhancing bone regeneration. In this study, a novel triangle-pillar porous scaffold was designed and made by polycaprolactone and hydroxyapatite produced by 3D printing, featuring channels and windows aligned in vertical and horizontal directions. To further enhance its bioactive potential, manuka oil-derived triketone was incorporated into the printing materials. Comprehensive characterisation confirmed that the scaffold exhibited high compressive strength and a uniform surface texture. In vitro assays demonstrated osteogenic differentiation, tube formation, and antimicrobial activity. Moreover, in vivo studies using rat subcutaneous and sheep femur defect models revealed significantly improved tissue integration and bone regeneration. Micro-CT and histological analyses showed that new bone grew inward toward the defect center along the window-guided pathways, closely mimicking the natural healing pattern. These findings suggest that the triangle-pillar channel scaffold represents a promising strategy for bone tissue engineering by integrating architectural optimization and biological cues to direct inward bone regeneration in a manner resembling the natural repair process.