The excellent mechanical strength and clinical reliability of titanium-based implants are key advantages of their applications in biomedical fields. However, their susceptibility to bacterial colonization and corrosion remains a major limitation, affecting long-term performance and compromising patient safety. The present study described a niobium pentoxide coating, applied using the spin coating technique followed by thermal annealing, as a viable surface modification approach that can be used to enhance the corrosion resistance and antibacterial performance of titanium dental implants. The Nb₂O₅ suspension was prepared under controlled conditions and subsequently deposited, in multiple layers, onto the substrate to form a uniform protective film. Electrochemical characterization by potentiodynamic polarization (Tafel analysis) demonstrated a significant decrease in the corrosion rate, from 0.0077 mm/year for uncoated to 0.0021 mm/year for coated titanium, representing a ~73% decrease in corrosion current density. These results proved that a stable passive layer had formed, enhancing surface stability in physiological media. Successful crystallization of Nb₂O₅ phases upon thermal treatment, as confirmed by XRD analysis, accounted for the enhanced electrochemical performance. Antibacterial properties against Staphylococcus aureus ATCC 25923 were evaluated by the agar diffusion method. Results obtained showed that the diameter of the inhibition zone had increased from 12.9 ± 0.4 mm (uncoated) to 15.1 ± 0.5 mm (coated), corresponding to a statistically significant improvement of 16.7% (p < 0.05). Enhanced antibacterial properties were related to changes in surface properties owing to the deposition of Nb₂O₅ films, leading to reduced bacterial adhesion and biofilm growth. Conclusion The Nb₂O₅ coating contributed significantly to the improvement of corrosion resistance and the antibacterial properties of the titanium implants, hence demonstrating biomedical relevance for future applications in dentistry.
