Titanium implants coated with a bifunctional molecule with antimicrobic activity: A rabbit study

Background: Various surface treatments have been tested for titanium implants aiming at increasing their surface biocompatibility and their biological characteristics, but also the efficiency of the implant surface will have to be improved to drastically decrease peri-implantite and mucosite. In fact, the peri-implantitis and peri-implant mucositis have a high incidence in clinical practice. The nanofabrication techniques that offer the possibility to achieve the implant surface that reduces bacterial colonization could influence the osteointegration. The aim of this research was to evaluate the bone response to titanium implants coated with a bifunctional molecule with antimicrobic activity consisting of a combination of silver ions covalently bound to titanium dioxide nanoparticles. Methods: A total of 36 implants were inserted into 18 older New Zealand white male rabbits. They had two different surfaces. The implants Control group was characterized by an acid-etched and sandblasted surface treatment, and the Test implants had an acid-etched and sandblasted surface coated with a silver ion covalently bound to titanium dioxide nanoparticles in the solution. Results: No statistically significant difference of the bone density was evidenced between Control and Test implants at two weeks (p-value = 0.623), four weeks (p-value = 0.339), and eight weeks (p-value = 0.461). Moreover, no statistically significant difference of the bone-implant contact percentage was evidenced between Control and Test implants at two weeks (p-value = 0.938), four weeks (p-value = 0.307), and eight weeks (p-value = 0.294). The effectiveness of the present investigation demonstrated no adverse effects on osseointegration, and no statistically significant differences were observed in the bone density and percentage of bone-implant contact between Test and Control implants at all the experimental time points (two, four, and eight weeks). Conclusions: Titanium implants coated with the silver-anatase solution bind very well to the bone and did not have an adverse effect on the bone tissue in a rabbit model. These facts suggest possible clinical applications for the silver composition.