Purpose: to prospectively identify radiographic and clinical factors associated with teeth that receive contemporary nonsurgical endodontic retreatment.
. •N= 337 failing RCT, scheduled for NSRC-Retx.
•All patients referred for management of failing endodontically treated teeth were initially examined to determine a diagnosis and decide upon the appropriate course of treatment.
•Endodontic failures that were extracted or surgically treated were not included in this evaluation.
•During the examination and treatment, the following factors were evaluated:
-pain (subjectively and objectively through percussion and palpation).
-Presence of resorption, perforation, root fracture, PA lesion . time elapsed sice primary treatment, type of filling material.
Quality or RCT (inadequate if it was >2 mm from RG apex, had obvious voids, overfilled >2mm beyond apex )
-Symmetry of RCT within the root was also observed (fig1)