The aim of this study was to analyze the timing of first fillings posteruptively in a cohort comprising 51 asthmatic children receiving inhaled corticosteroids and living in three communities in Ostrobothnia, Finland. They had all been born in the 1980s and had had asthma check-ups in the local asthma policlinic. A group of 102 healthy age- and sex-matched children served as controls. A longitudinal survival analysis of the timing of the first filling in the primary teeth and first permanent molars was conducted retrospectively using data from the annual dental health records. The timing of the first fillings in permanent first molars showed no statistically significant differences between asthmatic and healthy children, but the filling increments in the primary molars were consistently higher in the asthmatic group; the difference for the upper first primary molars was, for instance, statistically significant (risk ratio = 2.565; 95% confidence interval = 1.333-4.935). More extractions because of caries were also performed on primary molars in the asthmatic children. The findings support the hypothesis that factors related to the asthmatic condition might increase the risk of caries. A longer surveillance time would be needed to evaluate the effect of asthma on the permanent dentition.