Evaluation of the effects of different filling techniques applied in retreatment on postoperative pain and radiographic healing in single rooted permanent teeth with apical periodontitis

The aim of this study is to evaluate the effect of different filling techniques on the postoperative pain level and radiographical healing in single visit retreatment in single-rooted and single-canal teeth with apical periodontitis. A total of 63 (single-rooted, single-canal) teeth with unsuccessful root canal treatment of 48 systemically healthy patients (mean age 34.19+9.75 years) were included in the present study. Residual root canal filling materials were removed with Protaper Universal Retreatment rotary files (Dentsply, York, PA). All teeth were prepared using Protaper Next rotary files (Dentsply, York, PA). Then, the teeth were randomly divided into 3 groups according to the root canal filling technique applied (n=21); Root canal fillings were completed in a single visit using cold lateral compaction (CLC), continuous wave compaction (CWC), and thermoplasticized gutta-core (TGC) techniques. Permanent restorations were performed using direct composite resin in the same visit. Pain levels were evaluated using the Numerical Pain Scale (NRS) in all cases preoperatively, postoperatively, at the 3-rd hour, 24-th hour, 48-th hour, and 7- th day. PAI scores were recorded on periapical radiographs of all cases preoperatively and at 6 months postoperatively. The obtained data were analyzed statistically (IBM, Armonk, NY, USA). Statistically significant level was determined as 5%. As a result of the present study, it was found that there was significantly more postoperative pain at the 3-rd hour interval after CLC compared to the 7th-day interval (p<0.05). Significantly more postoperative pain was found after CWC both preoperatively and at the 3-rd hour compared to the 7-th day (p<0.05). There was no significant difference in terms of postoperative pain in all time intervals evaluated between filling techniques (p>0.05). After all root canal filling techniques were applied in all periods tested in the current study, no difference was found between the PAI scores recorded at the postoperative 6-th month of the teeth included in the study (p>0.05). As a result of the present study, CLC, CWC, and TGC root canal filling techniques were found to have similar efficacy in terms of radiographic improvement and postoperative pain at 6 months.