No abstract

Titanium and its alloys are used worldwide in surgery. Dental implants, screws and plates, prostheses, and surgical instruments are made with titanium-based metals. The favorable characteristics that make this material desirable for implantation are (a) mechanical proprieties and (b) biocompatibility. The latter has been demonstrated by in vivo studies with animal models and clinical trials over a 40-year period. However, the exact effect of titanium on cells is still not well characterized. Expression profiling by DNA microarray is a new molecular technology that allows the analysis of gene expression in a cell system. Several genes whose expression was significantly up- or downregulated in an osteoblast-like cell line (MG-63) on titanium were identified with the use of DNA microarrays containing 19,200 genes. The differentially expressed genes are associated with a broad range of functional activities, including apoptosis, vesicular transport, and structural function. It was also possible to detect some genes whose function is unknown. The data reported are, to the author's knowledge, the first genetic portrait of titanium-cell interaction. They may help to provide a better understanding of the molecular mechanisms of titanium biocompatibility and serve as a model for studying the biocompatibility of other materials.

Surface implant modifications have been shown to have a relevant importance in modifying cell response. Expression profiling by DNA microarray is a new molecular technology that allows the analysis of gene expression in a cell system. By using DNA microarrays containing 19,200 genes, we identified in osteoblast-like cells line (MG-63) on new implant surface (nanoPORE, Out-Link, Sweden and Martina, Due Carrare, Padova, Italy), several genes whose expressions were significantly down-regulated. The differentially expressed genes cover a broad range of functional activities: (a) immunity, (b) vesicular transport (c) apoptosis and cell cycle regulation. It was also possible to detect some genes whose function is unknown. The data reported are, to our knowledge, the first genetic portrait of an implant surface. They can be relevant to better understand the molecular mechanism of implant osseointegration and as a model for comparing other materials.