Unusual Response to Nickel in Orthodontic Wires and Brackets

In dentistry the metal nickel is a cause of concern for both orthodontists and general dentists. It is commonly used in the field of dentistry and is the most common cause of dermatitis or allergic response.^1,2,3 Nickel has sometimes been indicated as a biological and histological sensitizer that can cause short and long term reactions (Type IV immune response). However, it seldom results in discontinuance of treatment due to any severe adverse reactions to the patient.^4,5,6,7 We report on a patient undergoing routine orthodontic treatment. Within an hour following the placement of the orthodontic appliances (brackets) and wires the patient was rushed to the emergency room because of difficulty in breathing and the appearance of a significant generalized body rash. A diagnosis of extreme reaction to the metal nickel was made at the hospital. This article discusses the clinical and diagnostic aspects of orthodontic appliances containing the metal nickel and the histopathologic aspects of an allergic patient undergoing orthodontic treatment. It emphasizes the accuracy of a thorough patient health history and the completeness of the family history to allergies. Patients undergoing orthodontic care rarely experience allergies to the components within the orthodontic treatment appliances. Although there is mounting evidence that metal braces may be a contributor to localized gingival erythemia and hypertrophy of gingival tissue.^8,9,10 Most often better oral hygiene seems to ameliorate the condition. When any metal is used in fixed and removable orthodontic appliances the metal of choice is stainless steel and a component is metal nickel, atomic number 28. The presence of this metal has demonstrated on rare occasions to be a possible biological and histologic sensitizer to human tissues.^11,12 Although allergies that cause short term and long term reactions are rare they can still occur.^13,14,15 This is one such case. The health history is probably the most important part of assessing the criteria for patient care.