Allergic reactions and nickel-free braces: a systematic review

Abstract

Nickel-free braces have gained popularity as a viable alternative for patients who are allergic to nickel. The purpose of this systematic review was to determine whether evidence exists to justify the use of nickel-free brackets in orthodontic patients who are allergic to nickel. An electronic search was performed using 7 databases (MEDLINE, BBO, LILACS, Web of Science, EMBASE, BIREME and Cochrane Library), without restriction regarding year or language, with supplemental manual searching of the references of retrieved articles. The search strategy produced 89 papers. The data extraction and quality score of each paper were evaluated independently by two reviewers, once each. After selection based on the eligibility criteria, four papers, including 2 controlled clinical trials and 2 clinical trials, qualified for the final analysis. Quality assessment of the included articles was also performed. Nickel-free braces (Ni content -2% max.) seem to represent a viable alternative for orthodontic patients who are allergic to nickel. However, further in vivo studies, considering the immunology characteristics of patients, are needed to determine the clinical implications of the findings of this study.

Longitudinal assessment of periodontal status in patients with nickel allergy treated with conventional and nickel-free braces

“…30,31 Nickel-free stainless steel braces produced by Morelli (Monobloc) do not have a significant amount of nickel in their composition and may be a viable alternative for allergic patients, in agreement with previous studies. 4,9 However, this composition decreases their mechanical properties, because nickel considerably enhances resistance to oxidation and corrosion. 32 Thus, the presented results are relative specifically to the Morelli brackets.…”

“…[1][2][3][4][5][6] At the same time, there has been a tendency on the part of the industry to produce orthodontic materials with low concentrations of nickel (0.2% to 4%). Such appliances are denominated nickel-free and are advertised as releasing low quantities of nickel ions, which may diminish the allergic response in sensitive patients.…”

“…[7][8][9][10] A critical evaluation of the literature reveals little consistent evidence regarding the actual effectiveness of nickel-free appliances in orthodontic patients allergic to nickel. In a recent systematic review, Pazzini et al 4 found only four studies suggesting that nickel-free braces may favor orthodontic treatment in allergic patients, and the authors stress the need for clinical trials that can provide more consistent evidence with regard to this issue. Studies involving nickel-free braces may provide important information by first determining whether nickel is truly the agent responsible for triggering responses of an inflammatory and/or allergic nature.…”

Nickel: humoral and periodontal changes in orthodontic patients

“…[9][10][11][12][13] Periodontal conditions were worst in nickel allergic individuals when compared to the non-allergic throughout treatment. 9 The authors made a longitudinal comparison on the clinical condition of these individuals by means of Löe index for 12 months (one evaluation at every 3 months).…”

Orthodontic Scars

“…Nickel content is found in orthodontic wires, bands, brackets and headgears. 27 However, Intraoral signs and symptoms of nickel hypersensitivity are rare because the concentrations of nickel required to provoke a reaction in the mouth are higher than those needed on the skin as in the case of jewellery and ear piercing. Intraoral signs are highly variable and difficult to diagnose.…”