Urethanes PDMS-based: Functional hybrid coatings for metallic dental implants

In this study, we propose new polymeric coatings for metallic implants that impart biocompatibility and antibacterialfeatures to such surfaces. The starting material, poly(cyclic carbonate)-polydimethylsiloxane, wasprepared from carbon dioxide fixation and then sequentially reacted by aminolysis with an organoaminosilane,affording the formation of an urethanic polydimethylsiloxane-based material. Finally, a hybrid coating wasobtained by performing a sol-gel process on the metallic surfaces, catalyzed by phosphotungstic acid. We provideevidence that due to the polydimethylsiloxane segments governing the surface termination, the hybrid coatingsshow a hydrophobic character. Furthermore, due the presence of phosphotungstic acid in the upper surface, theadhesion of Gram-positive and Gram-negative bacteria is suppressed in 4 h of contact with aqueous bacterialcultures. In addition, the coatings presented a>70% cytocompatibility besides a low cytotoxicity, making theminteresting candidates as biocompatible materials and an alternative to avoiding the biofilm associated withbacterial infections.