The work at a dental clinic implies getting in contact with different chemical substances, which may cause temporary or permanent injury to the staff, primarily allergic reactions, but also local irritation, carcinogenic or toxic effects. Dentists and dental assistants belong to the professional groups most frequently experiencing work-related eczema. The chemical substances may originate from dental materials, such as mercury from amalgam and monomers from resin based materials. The substances may be released during preparation, polishing and removal of restorations. In addition, different biocides/chemical disinfectants are used for both clinical an infection control purposes. (Article in Danish)