The aim was to assess the distribution and pattern of caries development longitudinally in teenagers and adolescents whose treatment had been based on remineralizing rather than restorative strategies. A baseline cohort of 536 children was studied, using bite-wing radiographs, from 11 to 22 years of age. The results showed a slow but continuous increase in both enamel and dentin caries of approximal surfaces. At 21, 29% of all posterior approximal surfaces had enamel caries according to the radiographic diagnoses, 14% had dentin caries and another 5% were restored. At the age of 20 21, the skewed distribution of DMFS(appr) apparent at 12 and 15 had given way to a more uniform picture and the percentage of individuals with no decayed approximal surfaces (DMFS(appr) = 0) decreased from 71 at 12-13 to 28 at 20-21 years of age. The proportion of DFS(occl) in relation to all DFS decreased from 83% at 12 to 52% at 21. The occlusal, mesial and distal surfaces of the first molar accounted for 60% of all restored surfaces at 21.