Anti-corrosive efficiency of salvadora persica plant stick powder on SS 316L orthodontic wire in artificial saliva

Abstract

The efficacy of stainless steel 316L (SS 316L) orthodontic wire in mitigating corrosion within artificial saliva was scrutinized both in the presence and absence of Salvadora persica (SP) stick powder, employing electrochemical methodologies. Potentiodynamic polarization assessments demonstrated a notable cathodic shift in the corrosion potential of SS 316L upon the introduction of SP extract, which signifies a reduction in anodic dissolution rates. A marked enhancement in linear polarization resistance was recorded, corresponding to a diminished corrosion current density, thereby evidencing substantial corrosion mitigation. Data obtained from electrochemical impedance spectroscopy corroborated these observations, revealing an augmentation in impedance and charge transfer resistance alongside a reduction in double-layer capacitance, indicative of suppressed charge transfer at the SS 316L/electrolyte interface. Open-circuit potential (OCP) metrics demonstrated that the system incorporating SP presented more negative values relative to the control, reinforcing the inhibitory effect exerted by the constituents of SP. UV–Visible and FTIR spectral analyses substantiated the existence of bioactive compounds within SP powder, with minor shifts in spectral bands noted on the SS 316L surface subsequent to immersion, suggesting adsorption of SP constituents. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) imaging of SS 316L specimens exposed to SP-enhanced artificial saliva exhibited diminished surface degradation in comparison to the control samples. These findings imply that constituents of SP, characterized by polar functional groups (e.g., O, N, and S), engage with SS 316L ions, thereby facilitating the formation of a protective layer and augmenting corrosion resistance. This investigation underscores the prospective application of Salvadora persica in prolonging the durability of SS 316L orthodontic devices utilized within an oral milieu.