Osteogenic gene expression of canine bone marrow stromal cell and bacterial adhesion on titanium with different nanotubes.

Bacterial infection and osseointegration of implant-biomaterials all play important roles in the success of an orthopedic prosthesis or a dental-implant. In this work, we evaluated the osteogenic gene expression of canine bone marrow stromal cells (CBMSCs) and the adhesion of Staphylococcus aureus (ATCC 12598) on different diameter TiO2 nanotube layers. The CBMSCs cultured on 30 and 70 nm nanotubes displayed polygon shape, but obviously elongated when the diameter of nanotubes turned to 120 nm. A significant increase in CBMSCs proliferation by as much as about ∼300%, and osteogenic gene (RUNX-2, OPN, COL-1, and OCN) expression were observed on the 120 nm diameter nanotubes when compared to the smooth Ti. However, the adhesion of bacteria also increased with an increased tube diameter and reached highest value on 120 nm nanotubes after 4 h of incubation. ∼300–400% increase in bacterial attached to 120 nm nanotubes in contract to the smooth Ti. These data suggested reducing bacteria colonization should be considered when larger diameter nanotubes with better osteogenic property would be used as orthopedic implants or dental implants. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.