Bidossi A, et al. - The present study (in vitro ) was carried out to evaluate the microbial affinity to a titanium-niobium nitride (TiNbN) coating. Researchers examined adhesion and biofilm formation of clinical isolates of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Cutibacterium acnes on TiNbN-coated titanium discs in comparison with uncoated titanium and cobalt-chrome alloys discs, with either smooth or rough surfaces. This study conducted bacterial adhesion by counting adhered bacteria in the first hours of incubation, and the biofilm formation was done by means of a spectrophotometric assay and by confocal laser scan microscopy after 72 hours of incubation. These data imply that TiNbN-coated orthopedic implants do not improve PJIs risk while ameliorating tribological and surface properties could serve a valid choice to limit possible complications such as metal hypersensitivity, although the onset of a PJI is more complex than in an in vitro scenario.