Evaluation of biomechanical properties and early osseointegration of biomimetic bone trabecular Ti6Al4V scaffolds based on Voronoi design

Abstract

Ti6Al4V scaffolds demonstrate significant translational potential for bone defect reconstruction by virtue of their exceptional biocompatibility and corrosion resistance. However, achieving concurrent osseointegration enhancement and mechanical compatibility with native cancellous bone remains a critical design constraint. A trabecular bone-mimetic porous Ti6Al4V scaffold was fabricated via Voronoi-tessellated computer-aided design and selective laser melting. Precise modulation of pore architecture enabled controlled porosity. The mechanical properties of the scaffold were characterized through compression testing. Earlystage in vivo osseointegration was evaluated at weeks 4 and 12 in a rabbit femoral condyle defect model using histomorphometry and micro-computed tomography, with comparisons made against conventional strut-based and G-curved lattice structures. The Voronoi scaffold demonstrated an elastic modulus and yield strength comparable to cancellous bone, thereby mitigating stress-shielding effects. Additionally, according to the results from the biomechanics, computational fluid dynamics, and in vivo analyses, the scaffold demonstrated significantly enhanced osteogenic potential and superior bone-implant interface integration compared to the strut and triply periodic minimal surface (TPMS) designs. In conclusion, the Voronoi design provides an effective biomimetic strategy for fabricating porous titanium alloy bone scaffolds with enhanced osteogenic properties, which embody higher potential than conventional struts and TPMS structures in facilitating bone defect repair.