Electrochemical Behaviour of Dental Alloys in the Presence of Orange Extracts at Different Body Temperatures and Analysis of the Adsorbed Layer

A comparative study on the corrosion effect of dental alloys in the presence of natural and commercial forms of orange extracts at various human body temperatures in the oral medium is reported for the first time. Three titanium alloys, namely Ni–Ti, Pure Titanium, and Ti-6Al-4V were examined, and corrosion studies, such as Gravimetric analysis, Potentiodynamic polarization, and Electrochemical Impedance spectroscopy, were carried out. The Tafel and Nyquist plots revealed that the inhibitor showed mixed and anodic-type characteristics. A high polarization resistance of 5.51 × 10⁵ Ω cm² was recorded by Ni–Ti alloy at high body temperature with an overall corrosion rate of 0.0147. The formed oxide layer was then studied using UV–visible spectroscopy, FTIR, X-ray Diffraction, and Scanning electron Microscope. The UV and FTIR peaks ensure the formation of inhibitor coating, and SEM images clearly show the formed layer's nature, proving the adsorption with evidence. Furthermore, the study indicates that acidic extract in a neutral medium affects the implant alloy's nature. Therefore, Nitinol is considered a suitable implant material even at an elevated temperature.