Gene expression profiling and histomorphometric analyses of the early bone healing response around nanotextured implants

While in vitro studies have shown that nanoscale surface modifications influence cell fate and activity, there is little information on how they modulate healing at the bone-implant interface. Aim: This study aims to investigate the effect of nanotopography at early time intervals when critical events for implant integration occur. Materials & methods: Untreated and sulfuric acid/hydrogen peroxide-treated machined-surface titanium alloy implants were placed in rat tibiae. Samples were processed for DNA microarray analysis and histomorphometry. Results: At both 3 and 5 days, the gene expression profile of the healing tissue around nanotextured implants differed from that around machined-surface implants or control empty holes, and were accompanied by an increase in bone-implant contact on day 5. While some standard pathways such as the immune response predominated, a number of unclassified genes were also implicated. Conclusion: Nanotexture elicits an initial gene response that is more complex than suspected so far and favors healing at the bone-implant interface.