Department of Dental Materials Sciences, ACTA, University of Amsterdam, The Netherlands.
Dent Mater. 2012 May;28(5):548-53. doi: 10.1016/j.dental.2011.12.009. Epub 2012 Jan 20.
Nickel (Ni) is a potent sensitizer and may induce innate and adaptive immune responses. Ni is an important component of orthodontic appliances (8-50 wt%). Due to chemical and mechanical factors in the oral environment, Ni is released from these appliances. Retention wires are in situ for a long period of time.
To quantitatively evaluate the influence of mechanical loading and pH on the nickel release from orthodontic retention wires.
Five different types of multi-stranded wires (Original Wildcat, Noninium, Lingual retainer, Dentaflex 3-s, Dentaflex 6-s), were submersed for 24 h in either 10 ml of distilled water or lactic acid, both submitted to cyclic loading in a 3-point bending test (0×, 1000×, 10,000×). The solutions were analyzed by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS), and the data was statistically analyzed (ANOVA, p<0.05).
Mechanical loading has a strong effect on the Ni release from orthodontic retention wires, especially in distilled water. Acidity has more impact on Ni release when compared to mechanical loading. Manganese-steel "Ni-free" wires released quantifiable amounts of Ni due to trace elements of Ni within the wire.
All investigated wires release considerable amounts of Ni to which exposure may have biological implications.
镍（Ni）是一种有效的致敏原，可能会引起先天和适应性免疫反应。Ni 是正畸矫治器（8-50wt%）的重要组成部分。由于口腔环境中的化学和机械因素，Ni 会从这些矫治器中释放出来。保持器会在原位停留很长时间。
定量评估机械加载和 pH 值对正畸保持器中 Ni 释放的影响。
将 5 种不同类型的多股线（原始 Wildcat、Noninium、舌侧保持器、Dentaflex 3-s、Dentaflex 6-s）分别浸泡在 10ml 蒸馏水中或乳酸中 24 小时，均在三点弯曲试验中进行循环加载（0×、1000×、10000×）。通过电感耦合等离子体质谱法（ICP-MS）分析溶液，并对数据进行统计分析（ANOVA，p<0.05）。
机械加载对正畸保持器中 Ni 的释放有很强的影响，尤其是在蒸馏水中。与机械加载相比，酸度对 Ni 释放的影响更大。锰钢“无 Ni”线会释放出可量化的 Ni，这是由于线内存在 Ni 的微量元素。
所有研究的线都会释放出相当数量的 Ni，这可能会产生生物学影响。
