Purpose: To identify periapical changes in non-surgically retreated root filled teeth 20-27 years after root canal treatment.
N= 112 roots in 70 patients
•112 roots from 70 individuals could be evaluated radiographically 20-27 yrs after retreatment.
•The same roots had been studied previously at 10-17 years follow up.
•The periapical condition was analyzed and compared by 3 observers in 2 series of radiographs taken at 10-17 yr and 20-27 years follow up.
•Lost teeth during the follow up period were analyzed retrospectively for the reasons of extraction.
Most highlighted Results:
The success rate (roots with no PA) recorded at 10-17 yrs follow up was 85.7%. and it increased at 20-27 yrs follow up to 95.5%.
Favorable outcomes were observed in 11 roots that had PA at 10-17 yrs follow-up. 8 of them had PA preoperatively. 5 of them were with overfilled root filling material.
Delayed healing as a result of root overfilled with filling material explained most of the favorable outcomes observed many years after treatment.
28 roots were extracted during the observation period, endodontic seems to represent a minor reason for the extraction.
Persistent asymptomatic PA lesions may heal after an extended observation periods, specially in cases of overfilling.