Objective: To identify caries experience in two groups of children and adolescents using longitudinal data from the Swedish Quality Registry for Caries and Periodontal Diseases (SKaPa). Material and methods: Data from two groups (10- and 20-year-olds), 165,365 individuals, were observed retrospectively for 10 years. Using a three-trajectory caries model (3-TCM), individuals were assigned according to their caries development as: high (15%), moderate (45%), or low (40%). Caries experience was expressed using the decayed and filled surfaces (DFS) and dfs indices. The specific affected caries (SaC) index and a point prevalence measurement at age 6 years (PP-6) were also analyzed. Results: Over the observation period, significant differences were discovered between all three trajectories within the oldest group (20-year-olds). The mean DFS increase was significantly elevated for the high trajectory compared with the lower trajectories, 7.9 ± 10.2, 3.3 ± 2.9 and 0.2 ± 0.5 for the three trajectories respectively. In the youngest group (10-year-olds), the high trajectory combined with the SaC and PP-6 provided further information of those with the highest caries experience. Conclusions: The 3-TCM identified individuals with high caries experience in the permanent dentition; but to properly elucidate caries experience in the primary and mixed dentitions, a combination with other indices was needed.