IntroductionThe purpose of this randomized clinical trial was to evaluate healing after endodontic microsurgery (EMS) using mineral trioxide aggregate (MTA) versus EndoSequence root repair material (RRM; Brasseler, Savannah, GA) as root-end filling materials. MethodsTwo hundred forty-three teeth with persistent or recurrent apical periodontitis were randomly assigned to either the MTA or RRM group. EMS was performed, and follow-up visits with clinical and radiographic investigation were scheduled at 6, 12, and 24 months with follow-up cone-beam computed tomographic (CBCT) imaging after 12 months. ResultsOne hundred twenty teeth with an average follow-up of 15 months were evaluated. The overall success rate was 93.3% for periapical (PA) evaluation and 85% for CBCT evaluation. The RRM group exhibited 92% and 84% success rates as assessed on PA and CBCT imaging, respectively. The MTA group exhibited 94.7% and 86% success rates as assessed on PA and CBCT imaging, respectively. No significant difference was observed between the 2 groups. Microsurgical classification, root canal filling quality, root-end filling material depth, and root fracture were found to be significant outcome predictors. ConclusionsEMS is a predictable procedure with successful outcome both 2-dimensional and 3-dimensional radiographic evaluation when RRM or MTA was used as the root-end filling material.