Imani Mohammad Moslem, Delavarian Mohadeseh, Arab Sepideh, Sadeghi Masoud
Department of Orthodontics, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Department of Orthodontics, Faculty of Dentistry, Kerman University of Medical Science, Kerman, Iran.
Postepy Dermatol Alergol. 2019 Jun;36(3):261-266. doi: 10.5114/ada.2018.74520. Epub 2018 Mar 21.
The metals nickel (Ni) and chromium (Cr) can cause immunological sensitivity and adverse biological and cytotoxic effects.
To evaluate hair levels of these metals in patients undergoing fixed orthodontic treatment compared with controls.
Five databases - PubMed, Web of Science, Scopus, Cochrane Library, and ScienceDirect - were searched up to January 2018 for evaluation of the hair levels of nickel and/or chromium in patients undergoing fixed orthodontic treatment. To assess the study quality, the Newcastle-Ottawa Scale was used (NOS), and to compare hair Ni and Cr levels in the cases compared with the controls, a random-effects meta-analysis was performed by Review Manager 5.3 using standard mean differences (SMDs) and 95% confidence intervals (CIs).
Out of 38 studies in the databases searched, 6 studies were included in the meta-analysis. The pooled SMD of hair Ni levels between the cases and controls was 0.95 μg/g (95% CI: -0.09, 1.99; = 0.07), which showed that the Ni level was similar in the cases compared with the controls, and that for hair Cr levels was 0.88 μg/g (95% CI: -0.45, 2.21; = 0.20), so the Cr level was similar in the cases compared with the controls.
The slightly elevated hair levels of Ni and Cr in patients undergoing fixed orthodontic treatment suggest that changing the components of fixed orthodontic appliances can be considered as an acceptable solution in the future.
金属镍（Ni）和铬（Cr）可引起免疫敏感性以及不良的生物学和细胞毒性作用。
评估接受固定正畸治疗的患者与对照组相比这些金属在头发中的含量水平。
截至2018年1月，检索了五个数据库——PubMed、科学网、Scopus、考克兰图书馆和科学Direct——以评估接受固定正畸治疗患者头发中镍和/或铬的含量水平。为评估研究质量，使用了纽卡斯尔-渥太华量表（NOS），并且为比较病例组与对照组头发中镍和铬的含量水平，通过Review Manager 5.3使用标准均数差（SMD）和95%置信区间（CI）进行随机效应荟萃分析。
在检索的数据库中的38项研究中，有6项研究纳入了荟萃分析。病例组与对照组之间头发镍含量水平的合并SMD为0.95μg/g（95%CI：-0.09，1.99；P = 0.07），这表明病例组与对照组相比镍含量水平相似；头发铬含量水平的合并SMD为0.88μg/g（95%CI：-0.45，2.21；P = 0.20），所以病例组与对照组相比铬含量水平相似。
接受固定正畸治疗患者头发中镍和铬含量水平略有升高表明，未来可以考虑更换固定正畸矫治器的部件作为一种可接受的解决方案。
