In order to map variations in the operative treatment threshold for occlusal caries, a pre-coded questionnaire was sent to a random sample of 759 dentists in Norway, 923 in Sweden, and 173 in the Danish Public Dental Health Service inquiring about caries and treatment strategies. A further intention was to explore the type of operative treatment and filling material dentists in Scandinavia would use given an occlusal lesion in the lower 2nd molar in a 20-year-old. It is found that close to 70% of dentists in the 3 countries would put off carrying out operative treatment of occlusal caries until they registered a moderately sized cavity and/or any radiolucency in dentin. In Sweden, 26.7% of dentists and in Denmark 24.3% would postpone operative treatment until the lesion had a large cavity and/or until radiolucency could be observed in the middle third of the dentin; in Norway, only 11.5% of dentists indicated this. The majority of dentists in all 3 countries preferred to drill only the carious part of the fissure, though in Norway more dentists (30.9%) would tend to drill the whole fissure compared to their Swedish (23.4%) and Danish (9.5%) colleagues. The majority of Danish dentists (52.4%) suggested amalgam for restoring the occlusal surface, while 19.9% of Norwegian and 2.9% of Swedish dentists would use amalgam. Composite was the first material of choice for 71.5% of the Swedish dentists, the remaining 25.6% suggesting conventional glass ionomer cement, light-cured 'glass ionomer cement', or a combination of glass ionomer cement and composite. The corresponding values for the Norwegian dentists were 39.1% and 41.0%, respectively, and for the Danish dentists 29.2% and 18.4%. In Scandinavia, the leading strategy for occlusal caries seems to be to postpone operative treatment until a definite cavity or radiolucency in the outer third of dentin can be observed, and to carry out operative treatment only of the part of the fissure that is carious. Composite resin is the predominant material of choice in Sweden, while in Denmark the majority of dentists preferred amalgam. Composite, or composite in combination with glass ionomer cement material, was the choice of almost 80% of Norwegian dentists.