The synergistic effect of 3D-printed microscale roughness surface and nanoscale feature on enhancing osteogenic differentiation and rapid osseointegration

Abstract

Personalized precision therapy and rapid osseointegration are the main development directions of dental implants. 3D printing is a vital advanced manufacturing technology for personalized precision therapy. However, the osteogenesis of the 3D printed Ti6Al4V implants is unsatisfactory. From the bionic perspective, the hierarchical micro/nano-topography can mimic the microenvironment of the multilevel structure of natural bone tissue and may endow the implant surface with superior bioactivity. In the present study, the hierarchical micro/nano-topography was successfully fabricated by construction the nanoscale feature on 3D printed microscale roughness surface of 3D-printed Ti6Al4V implants by alkali-heat treatment and hydrothermal treatment. Then the cell biological responses in vitro and osseointegration performance in vivo were systematically evaluated. The hierarchical micro/nano-topography evidently increased the roughness, improved the hydrophilicity and accelerated the hydroxyapatite deposition and mineralization, which significantly enhanced the adhesion, differentiation and extracellular matrix mineralization of bone marrow derived mesenchymal stromal cells (BMSCs). Most importantly, the hierarchical micro/nano-topography on 3D-printed implants facilitated the new bone formation and rapid osseointegration in vivo. Our study suggested that 3D-printed implant with micro/nano-topography may be a promising candidate to be applied in orthopedic field to meet the need of customized therapy and rapid osseointegration.