Synergistic Enhancement of Osseointegration with Micro-Arc Oxidation Treated 3d-Printed Ti-24nb-4zr-8sn Scaffold Via Contact Osteogenesis and Low Elastic Modulus

Abstract

In our study, we employed 3D printing technology to fabricate a porous scaffold structure to further decrease the implant's structural stiffness, approximating that of cancellous bone. We then applied micro-arc oxidation (MAO) surface modification technology to create a microporous structure oxide ceramic layer on the scaffold's surface and interior. We prepared and characterized 3D-printed porous Ti2448 and Ti6Al4V scaffolds before and after MAO surface modification. In vitro cell experiments demonstrated that proliferation, adhesion, and osteogenesis abilities on the scaffold surface were enhanced following MAO treatment. The elemental composition of the oxide layer in MAO-Ti2448 was more conducive to osteogenesis than that in MAO-Ti6Al4V. After implanting the MAO-Ti2448 scaffold into a rabbit femoral condylar defect model, the osseointegration efficiency was increased in the contact osteogenesis mode. The synergistic effect of these two factors enhanced the quantity and quality of new bone trabeculae. A more stable in situ bone bridge connection was formed within the implant, accelerating the formation of an interlocking structure between the bone and implant and providing greater implantation stability. These findings suggest that the MAO-treated 3D-printed Ti2448 scaffold holds significant potential for bone defect repair materials.

Keywords: 3D printing, Ti2448, Low elastic modulus, micro-arc oxidation, Contact osteogenesis.