Modulation of human osteoblasts by metal surface chemistry

Abstract

The use of metal implants in dental and orthopedic surgery is continuously expanding and highly successful. While today longevity and load-bearing capacity of the implants fulfill the expectations of the patients, acceleration of osseo integration would be of particular benefit to shorten the period of convalescence. To further clarify the options to a ccelerate the kinetics of osseo integration, within this study,the osteogenic properties of structurally identical surfaces with different metal coatings were investigated. To assess the development and function of primary human osteoblastson metal surfaces, cell viability, differentiation, and gene expression were determined. Titanium surfaces were used as positive, and surfaces coated with gold were used as negative controls. Little differences in the cellular parameters tested for were found when the cells were grown ontitanium discs sputter coated with titanium, zirconium, niobium, tantalum, gold, and chromium. Cell number, activity of cell layer-associated alkaline phosphatase (ALP), and levels of transcripts encoding COL1A1 and BGLAP did not vary significantly in dependence of the surface chemistry.Treatment of the cell cultures with 1,25(OH)2D3/Dex,however, significantly increased ALP activity and BGLAP messenger RNA levels. The data demonstrate that the metallayer coated onto the titanium discs exerted little modulatory effects on cell behavior. It is suggested that the micro-environment regulated by the periimplant tissues is more effective in regulating the tissue response than is the mate-rial of the implant itself.