Timing and effect of fissure sealants on permanent molars: a study in Finland and Sweden.

Fissure sealants are frequently used in the Nordic countries for the prevention of caries in children. The aim here was to analyse their use and effect on dental health in children and adolescents in Finland and Sweden. A retrospective longitudinal population-based study was performed in northern Finland and Sweden, where different strategies have been adopted for sealing teeth. The timing of sealant and restoration placements up to 18 years was studied in representative samples of subjects born in the early 1980s in Kemi, Oulu, Raahe and Tornio in Finland (n = 908) and compared with a random sample of subjects from Norrbotten, Sweden (n = 634). A sensitive survival analysis method was applied to all the permanent molars separately (Virtanen et al. 1996). About 80-90% of molars had been sealed in the Finnish subjects, and approximately 30% in the Swedish cases, employing selective criteria. The filling increments were statistically significantly higher in Sweden than in Finland, although the differences were not of the same magnitude as the reduction in sealants. More than 30% of first molars and 50% of second molars had not been treated, i.e. were without sealants or fillings, by the end of the follow-up in Sweden, compared with 10% and 20%, respectively, in Finland. Fissure sealants were effective in preventing caries in molars in children and adolescents, and the use of selective criteria for targeting this treatment can yield savings in effort and costs in a low caries situation, although more research is needed to find the optimum cost-effective strategy.