Dental implants have emerged as one of the most consistent and predictable treatments in the oral surgery field. However, the placement of the implant is sometimes associated with bacterial infection leading to its loss. In this work, we intend to solve this problem through the development of a biomaterial for implant coatings based on 45S5 Bioglass® modified with different amounts of niobium pentoxide (Nb2O5). The structural feature of the glasses, assessed by XRD and FTIR, did not change in spite of Nb2O5 incorporation. The Raman spectra reveal the Nb2O5 incorporation related to the appearance of NbO4 and NbO6 structural units. Since the electrical characteristics of these biomaterials influence their osseointegration ability, AC and DC electrical conductivity were studied by impedance spectroscopy, in the frequency range of 102–106 Hz and temperature range of 200–400 K. The cytotoxicity of glasses was evaluated using the osteosarcoma Saos-2 cells line. The in vitro bioactivity studies and the antibacterial tests against Gram-positive and Gram-negative bacteria revealed that the samples loaded with 2 mol% Nb2O5 had the highest bioactivity and greatest antibacterial effect. Overall, the results showed that the modified 45S5 bioactive glasses can be used as an antibacterial coating material for implants, with high bioactivity, being also non-cytotoxic to mammalian cells.

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Molybdenum oxide thin films were deposited on stiff and flexible substrates by reactive DC magnetron sputtering. Two sets of samples were prepared. The first with different O2/Ar flow rate ratios and the second, fixing the oxygen content, with different time of deposition. As the O2/Ar flow rate ratio varies from 0 up to 0.56, a threshold was found, ranging from crystalline to amorphous nature, and from a nontransparent appearance with metallic-like electrical conductivity to transparent and dielectric behaviour. From the second set, all transparent, the MoOx films present a compact/dense and featureless morphology with thickness from 190 up to 910 nm, depending on the time of deposition. Their structure was corroborated by XPS and Rutherford Backscattering Spectrometry (RBS) and density measurements were performed by RBS and X-ray reflectivity (XRR), revealing a value of 2.4 g/cm3. The surface roughness is in the order of a few nanometers and the maxima optical transmission, in the visible range, is around 89%. Electrochemical cyclic voltammograms showed noticeable color reversibility and reproducibility on the flexible substrates opening new framework possibilities for new electrochomic devices.

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Biofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into 45S5 Bioglass®. By combining the regenerative properties of Bioglass® with the antimicrobial effects of copper, this material has the potential to prevent infections, enhance osseointegration and improve the long-term success of implants. Bioglasses modified with various concentrations of CuO (from 0 to 8 mol%) were prepared with the melt-quenching technique. Structural analysis using Raman and FTIR spectroscopies did not reveal significant alterations in the bioglasses structure with the addition of Cu. The antibacterial activity of the samples was assessed against Gram-positive and Gram-negative bacteria, and the results demonstrated significant inhibition of bacterial growth for the bioglass with 0.5 mol% of CuO. Cell viability studies indicated that the samples modified with up to 4 mol% of CuO maintained good cytocompatibility with the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the bioactivity assessment demonstrated the formation of a calcium phosphate (CaP)-rich layer on the surfaces of all bioglasses within 24 h. Our findings show that the inclusion of copper in the bioglass offers a significant enhancement in its potential as a coating material for implants, resulting in notable advancements in both antibacterial efficacy and osteointegration properties.