Effects of Various Mouthwashes on the Orthodontic Nickel-Titanium Wires: Corrosion Analysis

Abstract

OBJECTIVES: This project was carried out to identify the least corrosive mouthwash when Nickel Titanium (NiTi) wires are employed in the oral environment for longer periods during the orthodontic treatment. METHODOLOGY: Corrosion of NiTi archwires was investigated in different mouthwashes and artificial saliva. Artificial saliva was taken as a standard medium. A potentiodynamic test was performed using Gamry's potentiostat. This type of test comprises of a corrosion cell containing immersion medium, in which sample wire was dipped. A specified voltage was applied to complete electrochemical cell. Corrosion rate was calculated utilizing the Tafel equation through a software 'Echem analyst'. One-way ANOVA was conducted to compare the mean corrosion rates of wires immersed in different media. Field Emission Scanning Electron Microscope (FESEM) was used to analyze the surface characteristics of NiTi wires after the corrosion testing. RESULTS: NiTi wires tested in mouthwash containing HCl in 0.15% w/v of Benzydamine Hydrochloride (EnziclorTM) produced greatest corrosion (16.2300+4.405 MPY). While Dexapanthenol + permethol containing mouthwash (Hi-ParaentTM) showed minimum corrosion of the NiTi wires. The rate of corrosion was found to be insignificant in artificial saliva, the control medium. CONCLUSIONS: Research concludes that mouthwashes which contain dexapanthenol + permethol (e.g, Hi-ParadentTM) are the safest most among those containing chlorhexidine gluconate + benzydamine hydrochloride(e.g, EnzicloreTM) and sodium monofluorophosphate (e.g, SecureTM) in terms of corrosion of NiTi wires . KEYWORDS: Corrosion; Orthodontic wires, Nickel-titanium wires, Potentiodynamic analysis, Mouthwashes HOW TO CITE: Wajahat M, Moeen F, Husain SW, Siddique S, Khurshid Z. Effects of various mouthwashes on the orthodontic Nickel-Titanium wires: corrosion analysis