The burning mouth syndrome: Lack of a role for contact urticaria and contact dermatitis

Background: The burning mouth syndrome is poorly understood and mainly affects postmenopausal women. Dental allergens have seldom explained the burning. Objective: Eight patients (seven women, one man) (mean age 62.5 years) who wore dentures and had the burning mouth syndrome were investigated to determine whether contact urticaria, allergic contact dermatitis, or pressure urticaria played a role. Only patients who had minimal to no erythema of the mucosa were included. Methods: A complete blood cell count, fasting chemistry profile, and potassium hydroxide examination and cultures for Candida and dermatophytes were obtained. Contact urticaria and patch testing with control substances were performed with a panel of 25 potential denture allergens. Results: Complete blood cell counts and fasting chemistry profiles were normal. One positive Candida culture was found, but no improvement in the symptoms was noted after treatment. All patients tested positive to histamine and to at least two of the nonimmunologic urticaria controls. No patient had a positive urticarial reaction to the potential dental allergens. Two patients with nonimmunologic urticaria to cinnamic aldehyde improved with avoidance. All patch tests were negative. In the six patients tested for pressure urticaria, the results were negative. Conclusion: We cannot indict contact dermatitis, contact urticaria, or pressure urticaria as a cause of the burning mouth syndrome in the denture-wearing patient who has a normal-appearing mucosa. The burning symptoms in this syndrome may be secondary to a simple frictional phenomenon of the denture on the mucosa.