CORROSSION BEHAVIOUR OF NITI WIRES IN ARTIFIGIAL SALIVA AND FLUORIDE MOUTHWASHES
DOI:
https://doi.org/10.15332/us.v8i2.1171Keywords:
NiTi wires, Mouthwashes, Orthodontics, CorrosionAbstract
Objective: To determine the structural changes and the release of ions from NiTi wires in different solutions, such as artificial saliva and mouthwash with and without alcohol.
Methods: Twenty one arches of nickel-titanium alloy (55,6% Ni and 44% Ti), 0,016 inches were evaluated after being in contact with one of the three solutions tested (artificial saliva, mouthwash with and without alcohol) in cells thermostats to 37º C, speeding up the corrosion process through electrochemical polarization techniques: potentiodinámic, chronoamperometric and Impedance Spectroscopy.
Results: It was found a higher rate of corrosion on the wires subjected to mouthwash without alcohol, compared to rinsing with mouthwash with alcohol and artificial saliva, respectively (P<0.05). Although the artificial saliva presented a greater tendency to corrode equipment, the rate of corrosion was lower compared with the mouthwashes.
Conclusions: The low potential for corrosion signs shown that the material presents a small range of stability and any change in temperature or pH conditions, can cause them to corrode. The dissolution of nickel ions was less than the considered toxic to the human body.
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References
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