Screening the Optimal Patterned Surfaces Consisting of Cell Morphology Mimicking Micro-pillars and Nanotube Arrays for the Design of Titanium Implants

Abstract Micron/nano scale topographic modification has been a significant focus of interest in current titanium (Ti) surface design. However, the influence of micron/nano structured surface on cell or bacterium behavior on the Ti implant has rarely been systematically evaluated. Moreover, except for popular microgrooves, little work has been carried out on the reaction of cells to the bionic structure. In this study, several micro-pillars mimicking cell morphology were prepared on Ti surfaces by lithography and contact printing (ICP) method, and they were further decorated with nanotube arrays by anodization technology. These surface modifications remarkablly increased the surface roughness of pristine Ti surface from 91.17 nm ± 5.57 nm to be more than 1000 nm, and reduced their water contact angles from 68.3° ± 0.7° to be 16.9° ± 2.4°. Then, the effects of these hierarchical micron/nano scale patterns on the behaviors of MG63 osteoblasts, L929 fibroblasts, SCC epithelial cells and P. gingivalis were studied, aiming to evaluate their performance in osseointegration, gingival epithelial sealing and antibacterial ability. Through an innovative scoring strategy, our findings showed that square micro-pillars with 6 µm width and 2 µm height combined with 85 nm diameter nanotubes was suitable for implant neck design, while square micro-pillars with 3 µm width and 3.6 µm height combined with 55 nm diameter nanotubes was the best for implant body design. Our study reveals the synergistic effect of the hierarchical micron/nano scale patterns on MG63 osteoblasts, L929 fibroblasts, SCC epithelial cells and P. gingivalis functions. It provides insight into the design of biomedical implant surfaces.