Influence of Colgate mouthwash on corrosion resistance of orthodontic wire made of Ni-Ti alloy immersed in artificial saliva

This study investigates the corrosion resistance of orthodontic wire made of Ni-Ti alloy when immersed in artificial saliva, both in the absence and presence of Colgate mouthwash. The evaluation was carried out using potentiodynamic polarization techniques and electrochemical impedance spectroscopy (EIS). Polarization results show that the presence of Colgate mouthwash reduces the corrosion resistance of the Ni-Ti alloy, as indicated by a decrease in linear polarization resistance and an increase in corrosion current. EIS analysis confirms this trend, revealing reductions in charge transfer resistance, impedance magnitude, and phase angle, along with an increase in double-layer capacitance. These findings suggest that the aggressive components in Colgate mouthwash accelerate corrosion processes. Therefore, individuals wearing orthodontic appliances composed of Ni-Ti alloy are advised to avoid using Colgate mouthwash to prevent potential degradation of their dental wires.