Trabecular-like Ti–6Al–4V scaffold for bone repair: A diversified mechanical stimulation environment for bone regeneration

Abstract

A bionic scaffold with ideal osteoconductive and osteoinductive characteristics is in urgent demand. The trabecular-like scaffold and corresponding regular scaffold with cubic cells were designed through Voronoi diagram and fabricated using L-PBF process. High-cycle fatigue test, fluid simulation, bone regeneration model prediction, and in vivo experiments were conducted. The research results revealed that the irregular structure significantly weakened the fatigue property of the trabecular-like scaffold, embodied by fast ratcheting strain accumulation and premature appearance of damage strain. The trabecular-like scaffold showed similar fluid behaviors to the CT-reconstructed cancellous bone, including permeation rate, pressure, velocity, and shear rate. It could be roughly concluded that there was a diversified mechanical stimulation environment formed in irregular structure, involving micro deformation, mass transportation, fluid shear stress and pressure, biological factor diffusion, better matching the demand for osteogenic mechanical stimulation, consequently making the implanted trabecular-like scaffold show better osteogenic ability than the regular scaffold.