Huang Gui-Yue, Jiang Heng Bo, Cha Jung-Yul, Kim Kwang-Mahn, Hwang Chung-Ju
Department of Orthodontics, College of Dentistry, Yonsei University, Seoul, Korea.
Department and Research Institute of Dental Biomaterials and Bioengineering, College of Dentistry, Yonsei University, Seoul, Korea.
Korean J Orthod. 2017 Sep;47(5):306-312. doi: 10.4041/kjod.2017.47.5.306. Epub 2017 Jul 27.
The purpose of this study was to examine the effect of commercially available fluoride-containing oral rinses on the corrosion behavior of titanium alloys, which are the main components of orthodontic miniscrews.
Four commercially available oral rinses (solution A, pH 4.46/260 ppm fluoride; solution B, pH 4.41/178 ppm fluoride; solution C, pH 6.30/117 ppm fluoride; and solution D, pH 4.17/3.92 ppm fluoride) were tested on titanium alloy (Ti-6Al-4V) circular plates, and saline was used as the control. The open-circuit potential and potentiodynamic polarization of these materials were measured. Thereafter, all samples were evaluated under a field-emission scanning electron microscope.
Among the tested oral rinses, except solution D, the more the fluoride content was, the greater was the corrosion potential downtrend; the corrosion resistance of the titanium alloy sample was also lowered significantly ( < 0.05). Field-emission scanning electron microscopic analysis of the surface morphology of the titanium alloy samples revealed that all samples had some defects, crevices, or pitting after exposure to the oral rinses than before treatment. In particular, the samples in solution A showed the most changes.
Commercially available oral rinses having a high fluoride concentration and a low pH may reduce the corrosion resistance of titanium alloys used in dental appliances such as orthodontic titanium miniscrews and brackets.
本研究旨在探讨市售含氟口腔含漱液对正畸微螺钉主要成分钛合金腐蚀行为的影响。
在钛合金（Ti-6Al-4V）圆板上测试四种市售口腔含漱液（溶液A，pH 4.46/氟含量260 ppm；溶液B，pH 4.41/氟含量178 ppm；溶液C，pH 6.30/氟含量117 ppm；溶液D，pH 4.17/氟含量3.92 ppm），并用生理盐水作为对照。测量这些材料的开路电位和动电位极化。此后，所有样品在场发射扫描电子显微镜下进行评估。
在测试的口腔含漱液中，除溶液D外，氟含量越高，腐蚀电位下降趋势越大；钛合金样品的耐腐蚀性也显著降低（<0.05）。对钛合金样品表面形态的场发射扫描电子显微镜分析表明，与处理前相比，所有样品在接触口腔含漱液后均有一些缺陷、缝隙或点蚀。特别是，溶液A中的样品变化最大。
高氟浓度和低pH值的市售口腔含漱液可能会降低正畸钛微螺钉和托槽等牙科器械中使用的钛合金的耐腐蚀性。
