Non-surgical endodontic retreatment may be divided into categories example coronal disassembly, locating previously missed canals, removing obturation materials, negotiating blocks, bypassing ledges, repairing perforations, treatment planning fractures etc. This randomised clinical trial revealed a preference for a single visit rather than two-visit nonsurgical retreatment as it significantly decreased the postoperative pain in patients with a root canal–treated teeth.

This study aimed to evaluate postoperative pain after single-visit and 2-visit non-surgical endodontic retreatments with 2 different intracanal medicaments.

A total of 150 patients with an asymptomatic root canal–treated teeth in need of nonsurgical endodontic retreatment were randomly divided into 3 groups having 50 patients each. Patients were picked randomly from those who were without preoperative pain. The patients in group 1 (single visit) were treated in a single visit. Calcium hydroxide and Chlorhexidine (CHX) were used as intracanal medicaments in group 2 and 3 patients in different visits. After 1, 2, 3, and 7 days and 1 month after treatment, the presence of postoperative pain was evaluated. The 2-visit treatments were completed 1 week after the first visit. Mann-Whitney U, Kruskal-Wallis, and Pearson chi-square tests (α = 0.01, 0.05) were used to analyse the data. 

Postoperative pain was remarkably higher in the CHX group in comparison with the single-visit group on the first day of evaluation. On day 2, postoperative pain was significantly less in the single-visit group than in the other 2 groups. No remarkable differences among the groups on the third and seventh days of assessment were observed. At the 1-month evaluation, postoperative pain was significantly higher in both the calcium hydroxide and CHX group in comparison with the single-visit group.

Based on the assessments ranging from 1 day to 1 month it was concluded that single-visit nonsurgical endodontic retreatment was associated with fewer incidences of postoperative pain as compared to 2-visit nonsurgical endodontic retreatment.