Further Interventions after Root Canal Treatment Are Most Common in Molars and Teeth Restored with Direct Restorations: A 10-11-Year Follow-Up of the Adult Swedish Population.

The frequency numbers of nonsurgical retreatment and root-end surgery were low, despite 1 in 5 root-filled teeth registered as extracted. Further interventions were most common in molars and directly restored teeth. Endodontic retreatments were performed more often during the first 4 years.