Many oral diseases are caused by the accumulation of biofilms, which are complex microbial communities composed mostly of bacteria and fungi. Peri-implantitis, characterized by the loss of soft and hard tissue around dental implants, is an example of a problematic disease caused by mature biofilms. Mature biofilms are difficult to remove because of extracellular polymeric substances (EPS), which protect and stabilize the biofilm. Thus, it may be strategic to target the adhesion of early colonizing bacteria such as Streptococcus sanguinis and Staphylococcus aureus around oral implant abutments to prevent biofilm formation and peri-implantitis. 

Previous studies have found that both copper nanoparticles (CuNP) and hierarchical topography can inhibit bacterial adhesion and biofilm formation. In this proposed experiment, titanium (Ti) discs, which represent the implant abutments, are to be modified with a CuNP coating and/or a hierarchical topography in order to discover the combinative effects on adhesion and biofilm formation of S. sanguinis and S. aureus. To allow for the adhesion of copper nanoparticles, a polydopamine (PDA) layer must first be created on the Ti discs. Then, a simple dip-coating process in which the Ti samples are immersed in CuCl2 (0.1mmol/L) for 1 hour is used to coat the samples with CuNPs.

We can expect the most inhibition of adhesion of bacteria and biofilm formation on the hierarchical/CuNP modified Ti disc, as opposed to the unmodified control Ti discs. Additionally, we expect non-toxic levels of CuNP leaching as well as no cytotoxic effects on tested fibroblasts and preosteoblasts.

Overall, these surface modification methods may provide an effective way to limit bacterial adhesion on implant abutments, thus reducing the likelihood of the development of peri-implantitis in oral implant patients.

If you have any questions or would like to learn more, email: heoj@sas.upenn.edu