Heravi Farzin, Moayed Mohamad Hadi, Mokhber Nima
Department of Orthodontics, School of Dentistry Mashad University of Medical Sciences, Mashhad, Iran.
Department of Materials and Metallurgical Engineering, Ferdowsy University, Mashhad, Iran.
J Dent (Tehran). 2015 Jan;12(1):49-59.
The commonly used Nickel-Titanium (NiTi) archwires in orthodontic treatment are often exposed to fluoride-containing mouthwashes. The aim of this in-vitro study was to evaluate and compare the corrosion resistance of three commercially available NiTi archwires exposed to 0.05 wt% and 0.2 wt% fluoride mouthwashes.
Three different types of NiTi archwires, 0.016″ in diameter, from Dentaurum, Global, and GAC, and a stainless steel archwire from Dentaurum were examined to assess their corrosion resistance in Fusayama-Meyer artificial saliva and in two other artificial saliva containing 0.05 wt% and 0.2 wt% sodium fluoride (NaF). After the primary setup of wires, they were tested by potentiodynamic and potentiostatic polarization and corrosion potential/time analyses. Their surfaces were evaluated using a scanning electronic microscope (SEM).
The results showed that all the wires were passive in artificial saliva. In contrast, by adding fluoride ions to the solution, the decrease in the archwires' corrosion resistance was in direct proportion to the increase in fluoride concentration.
The NiTi wires experienced deterioration of their corrosion properties under the effect of fluoride but not as much as the stainless steel archwires.
正畸治疗中常用的镍钛（NiTi）弓丝经常会接触含氟漱口水。本体外研究的目的是评估和比较三种市售NiTi弓丝在接触0.05 wt%和0.2 wt%含氟漱口水时的耐腐蚀性。
检测了三种不同类型、直径为0.016英寸的NiTi弓丝（分别来自Dentaurum、Global和GAC）以及一根来自Dentaurum的不锈钢弓丝，以评估它们在舟山市人工唾液以及另外两种含0.05 wt%和0.2 wt%氟化钠（NaF）的人工唾液中的耐腐蚀性。在对弓丝进行初步设置后，通过动电位和恒电位极化以及腐蚀电位/时间分析对它们进行测试。使用扫描电子显微镜（SEM）对其表面进行评估。
结果表明，所有弓丝在人工唾液中均呈钝态。相比之下，通过向溶液中添加氟离子，弓丝耐腐蚀性的降低与氟浓度的增加成正比。
NiTi弓丝在氟的作用下其腐蚀性能有所恶化，但不如不锈钢弓丝严重。
