The role of allergy in oral mucosal diseases.

We retrospectively assessed the prevalence of positive results to cutaneous patch testing, and the relevance of exclusion of identified allergens in the disease process, in 1252 patients with oral mucosal diseases presenting to the Department of Oral Medicine in Glasgow Dental Hospital and School and referred to the Contact Dermatitis Investigation Unit in Glasgow Royal Infirmary. The prevalence of patch-test positivity in each disease cohort was compared with that in 100 control volunteers. Patients with oral mucosal diseases were significantly more likely to have demonstrable hypersensitivity to food additives, especially benzoic acid, and perfumes and flavourings, especially cinnamaldehyde, than controls, and avoidance therapy caused improvement in the majority. Patch testing and the resultant avoidance therapy are useful adjuncts in the management of oral mucosal diseases.