International Journal of Nanomedicine (Jun 2017)
In vitro studies of nanosilver-doped titanium implants for oral and maxillofacial surgery
Abstract
Rafał Pokrowiecki,1,2 Tomasz Zaręba,3 Barbara Szaraniec,4 Krzysztof Pałka,5 Agnieszka Mielczarek,6 Elżbieta Menaszek,7 Stefan Tyski3,8 1Center for Cranio-Maxillo-Facial Surgery, Voivodeship Children’s Hospital, Olsztyn, 2Department of Oral Surgery, Jagiellonian Medical University, Kraków, 3Department of Antibiotics and Microbiology, National Medicines Institute, Warsaw, 4Faculty of Material Science and Ceramics, AGH University of Science and Technology, Kraków, 5Department of Materials Engineering, Lublin University of Technology, Lublin, 6Department of Conservative Dentistry, Medical University of Warsaw, Warsaw, 7Department of Cytobiology, Collegium Medicum, Jagiellonian University, Kraków, 8Department of Pharmaceutical Microbiology, Medical University of Warsaw, Warsaw, Poland Abstract: The addition of an antibacterial agent to dental implants may provide the opportunity to decrease the percentage of implant failures due to peri-implantitis. For this purpose, in this study, the potential efficacy of nanosilver-doped titanium biomaterials was determined. Titanium disks were incorporated with silver nanoparticles over different time periods by Tollens reaction, which is considered to be an eco-friendly, cheap, and easy-to-perform method. The surface roughness, wettability, and silver release profile of each disc were measured. In addition, the antibacterial activity was also evaluated by using disk diffusion tests for bacteria frequently isolated from the peri-implant biofilm: Streptococcus mutans, Streptococcus mitis, Streptococcus oralis, Streptococcus sanguis, Porphyromonas gingivalis, Staphylococcus aureus, and Escherichia coli. Cytotoxicity was evaluated in vitro in a natural human osteoblasts cell culture. The addition of nanosilver significantly increased the surface roughness and decreased the wettability in a dose-dependent manner. These surfaces were significantly toxic to all the tested bacteria following a 48-hour exposure, regardless of silver doping duration. A concentration of 0.05 ppm was sufficient to inhibit Gram-positive and Gram-negative species, with the latter being significantly more susceptible to silver ions. However, after the exposure of human osteoblasts to 0.1 ppm of silver ions, a significant decrease in cell viability was observed by using ToxiLight™ BioAssay Kit after 72 hours. Data from the present study indicated that the incorporation of nanosilver may influence the surface properties that are important in the implant healing process. The presence of nanosilver on the titanium provides an antibacterial activity related to the bacteria involved in peri-implantitis. Finally, the potential toxicological considerations of nanosilver should further be investigated, as both the antibacterial and cytotoxic properties may be observed at similar concentration ranges. Keywords: biomaterials, dental plaque, peri-implantitis, peri implant mucositis, silver, nanotechnology, nanomedicine