Osteogenic activity of titanium surfaces with nanonetwork structures

Abstract

Helin Xing,1,2 Satoshi Komasa,3 Yoichiro Taguchi,4 Tohru Sekino,5 Joji Okazaki3 1Department of Prosthetic Dentistry, School of Stomatology, The Fourth Military Medical University, Xi’an, People’s Republic of China; 2Graduate School of Dentistry (Removable Prosthodontics and Occlusion), 3Department of Removable Prosthodontics and Occlusion, 4Department of Periodontology, Osaka Dental University, Hirakata, Osaka, Japan; 5Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Aoba-ku, Sendai, Japan Background: Titanium surfaces play an important role in affecting osseointegration of dental implants. Previous studies have shown that the titania nanotube promotes osseointegration by enhancing osteogenic differentiation. Only relatively recently have the effects of titanium surfaces with other nanostructures on osteogenic differentiation been investigated. Methods: In this study, we used NaOH solutions with concentrations of 2.5, 5.0, 7.5, 10.0, and 12.5 M to develop a simple and useful titanium surface modification that introduces the nanonetwork structures with titania nanosheet (TNS) nanofeatures to the surface of titanium disks. The effects of such a modified nanonetwork structure, with different alkaline concentrations on the osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMMSCs), were evaluated. Results: The nanonetwork structures with TNS nanofeatures induced by alkali etching markedly enhanced BMMSC functions of cell adhesion and osteogenesis-related gene expression, and other cell behaviors such as proliferation, alkaline phosphatase activity, extracellular matrix deposition, and mineralization were also significantly increased. These effects were most pronounced when the concentration of NaOH was 10.0 M. Conclusion: The results suggest that nanonetwork structures with TNS nanofeatures improved BMMSC proliferation and induced BMMSC osteogenic differentiation. In addition, the surfaces formed with 10.0 M NaOH suggest the potential to improve the clinical performance of dental implants. Keywords: nanotopography, osseointegration, surface modification, bone marrow mesenchymal stem cells