OBJECTIVE: The aim was to study periapical status and the technical quality of root-filled teeth in Swedish adolescents and young adults in Malmö, Sweden. MATERIAL AND METHODS: The sample, collected from dental records in the Public Dental Service, consisted of notes and radiographs of all root-filled permanent teeth in all 19-year-olds born in 1979 (mean age at root filling=16.2 years). The sample for assessing periapical status and technical quality consisted of 124-153 teeth. The criterion for inclusion for assessing periapical status was a follow-up time of at least one year. Periapical status was assessed with the Periapical Index (PAI). Technical quality was analyzed from radiographs in two respects: sealing quality of the root canal and distance from the root filling to the radiographic apex. The radiographs were analyzed independently by two observers with inter-examiner kappa values of 0.82-0.85. RESULTS: Apical periodontitis was found in 52% of the teeth and occurred significantly more often among molars than among anterior teeth. As judged radiographically, 51% of the teeth were inadequately sealed. In 38%, the distance to the apex was >2 mm and overfilling was registered in 14% of the teeth. Compared with anterior teeth, significantly more root fillings of molars had a distance to the apex of >2 mm. Technical quality was statistically significantly correlated with periapical status at follow-up. CONCLUSIONS: The technical quality and periapical status of root-filled teeth in adolescents and young adults were unsatisfactory in about half of the teeth.