Premium
Determination of corrosion rate of orthodontic wires based on nickel‐titanium alloy in artificial saliva
Author(s) -
Katić V.,
Ćurković L.,
Ujević Bošnjak M.,
Špalj S.
Publication year - 2014
Publication title -
materialwissenschaft und werkstofftechnik
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.285
H-Index - 38
eISSN - 1521-4052
pISSN - 0933-5137
DOI - 10.1002/mawe.201400201
Subject(s) - nickel titanium , corrosion , metallurgy , materials science , alloy , nickel , inductively coupled plasma , rhodium , saliva , titanium , nuclear chemistry , shape memory alloy , chemistry , plasma , catalysis , biochemistry , physics , quantum mechanics
The goal of this study was to determine corrosion behavior of three orthodontic wires based on nickel‐titanium alloy (NiTi) in artificial saliva at temperature of 37 °C as function of immersion time. Following orthodontic wires were used: uncoated (NiTi), rhodium coated (Rh NiTi) and nitrified (N NiTi) orthodontic wires. Corrosion of investigated orthodontic wires were monitored by measuring of Ni 2+ and Ti 4+ ions released in artificial saliva by inductively coupled plasma‐optical emission spectroscopy (ICP‐OES) after 3, 7, 14, 21 and 28 days of immersion. Obtained results indicate that corrosion reaction of the NiTi wires in artificial saliva follows the parabolic rate law. According to the obtained values of parabolic corrosion rate constants, corrosion susceptibility of orthodontic wires decreases in the following order: Rh NiTi wire (K p = 2.48 μg 2 /cm 4 h) > NiTi wire (K p = 1.6 × 10 –3 μg 2 /cm 4 h) > N NiTi wire (K p = 6.0 × 10 –4 μg 2 /cm 4 h). These results indicate that in comparison with uncoated NiTi wire, rhodium coating significantly increases corrosion susceptibility, while nitrification effectively suppresses the release of Ni 2+ and Ti 4+ ions.