Oral mucosal diseases investigated by patch testing with a dental screening series

The rôle of contact allergies in oral mucosal diseases was studied. The subjects were 24 patients out of 479 tested, who had oral mucosal symptoms and positive patch test reactions in a dental series during 1987-1994 at the Department of Dermatology, Helsinki University Hospital. The clinical diagnoses were oral lichen planus (LPO, 13 patients), leukoplakia (2), glossodynia, i.e., 'burning mouth syndrome' (4), stomatitis (3) and recurrent angioedema (2). Only 1 patient had symptoms in relation to dental care. All but 2 patients had allergic reactions to mercury (Hg) (12 patients), gold sodium thiosulfate (Au) (13 patients) or both. A clinical connection between oral symptoms and contact allergy was seen in 10 patients. 9 patients (7 LPO, 2 leukoplakia) had Hg allergy. In these cases, the oral lesions disappeared after the amalgam fillings had been removed. 1 patient had recurrent stomatitis and perioral eczema after dental care and 2,2-bis(4-(2-hydroxy-3-methacryloxypropoxy)phenyl)propane (BIS-GMA) allergy. Her symptoms were caused by drilling of acrylic fillings. In addition, a connection between localized stomatitis and contact allergy was considered probable in 2 cases. 1 patient had stomatitis from contact with an orthodontic device and nickel allergy. The other had stomatitis from contact with a dental gold crown and gold allergy. No clinical connection was found between gold allergy and the oral symptoms of other patients.