Purpose: to classify the different clinical situations encountered in retreatment cases and relate them to the outcome after an observation period of 24 months.
n: 425. Patients were included if clinical S&S were present or PARL.
1- Root canal morphology respected RCMR: Calcifications, apical stop, broken instrument, and underfilled.
2- Root canal morphology altered RCMA:
Internal or external transpiration, perforation, stripping, and internal resorption.
-Instrumentation using crown down tech with rotary NiTi files. Obturation using WVC with GP cones and ZnO sealer.
-Crowns and post if needed were placed after 30 of Retx.
-The recall rate was 94%
-Pre and post operative radiographs were taken and teeth with PARL larger than 5 mm were not included.
-Postoperative classification of healing was: Healed, incomplete healing, and failure. Succes is defined by the sum of healed and incompletely healed cases.
-92% success in RCMR group with no PAL; 84% success in RCMR group with PAL.
-85% success in RCMA group with no PAL; 40% success in RCMA group with PAL.
-Overall success was 83.3% for the RCMR group and 49% for the RCMA group.
-Results are shown in Table.1,2.
-Respecting the root canal morphology is associated with a higher success than altered root canal morphology.