Contact allergies to nickel sulfate, gold sodium thiosulfate and palladium chloride in patients claiming side-effects from dental alloy components.

397 patients claiming various subjective symptoms related to dental restoration materials have been tested for the presence of metal allergy. The resultant data have been compared with the corresponding allergies of eczematous patients. The frequency difference of metal allergy in the dental group is statistically significant or close to significance for nickel sulfate, potassium dichromate, cobalt chloride, palladium chloride and gold sodium thiosulfate. The findings suggest that the dental patient group represents a subgroup with a high frequency of metal allergy.