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Cytocompatible bioactive surface treatments conferring antibacterial properties to osseointegrated dental implants are highly requested to prevent bacteria-related peri-implantitis. Here we focus on a newly designed family of mesoporous coatings based on zirconia (ZrO2) microstructure doped with gallium (Ga), exploiting its antibacterial and pro-osseo-integrative properties. The ZrO2 films were obtained via sol–gel synthesis route using Pluronic F127 as templating agent, while Ga doping was gained by introducing gallium nitrate hydrate. Chemical characterization by means of x-ray photoelectron spectroscopy and glow discharge optical emission spectroscopy confirmed the effective incorporation of Ga. Then, coatings morphological and structural analysis were carried out by transmission electron microscopy and selected area electron diffraction unveiling an effective stabilization of both the mesoporous structure and the tetragonal ZrO2 phase. Specimens’ cytocompatibility was confirmed towards gingival fibroblast and osteoblasts progenitors cultivated directly onto the coatings showing comparable metabolic activity and morphology in respect to controls cultivated on polystyrene. The presence of Ga significantly reduced the metabolic activity of the adhered oral pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in comparison to untreated bulk zirconia (p < 0.05); on the opposite, Ga ions did not significantly reduce the metabolism of the oral commensal Streptococcus salivarius (p > 0.05) thus suggesting for a selective anti-pathogens activity. Finally, the coatings’ ability to preserve cells from bacterial infection was proved in a co-culture method where cells and bacteria were cultivated in the same environment: the presence of Ga determined a significant reduction of the bacteria viability while allowing at the same time for cells proliferation. In conclusion, the here developed coatings not only demonstrated to satisfy the requested antibacterial and cytocompatibility properties, but also being promising candidates for the improvement of implantable devices in the field of implant dentistry.

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Titanium and its alloys represent the gold standard for osteointegrated implants, but their characteristic bioinertness still hinders their optimal integration within the host tissues. This limitation can be overcome by introducing osteoinductive functionalities on their surface. Plasma electrolytic oxidation (PEO) has emerged as a cost‐effective and rapid electrochemical method for generating bioactive titanium dioxide (TiO2) coatings, but the incorporation of pro‐osteogenic cations with this technique is typically passive and, in turn, characterized by a low efficiency. Here, alternate current (AC) PEO is investigated as a flexible solution to incorporate zinc into TiO2 coatings by exploiting the active transport of cations during the cathodic phase of the process. The resulting microporous surfaces show a greater zinc incorporation and an increased presence of rutile domains compared to conventional direct current (DC) PEO coatings, without, however, yielding significant morphological differences. In vitro assays with human mesenchymal stem cells (hMSCs) reveal an increased metabolic activity of cells adhering onto AC PEO surfaces. In addition, the increased expression of osteogenic differentiation markers (RUNX2 and osteocalcin) indicates significant surface‐driven osteoinductive effects, particularly for coatings grown by applying a short cathodic spike. Taken together, these aspects make Zn‐doped AC PEO surfaces a promising solution for osteoinductive orthopedic and dental applications.