Postoperative pain after removal of gutta-percha from root canals in endodontic retreatment using rotary or reciprocating instruments: a prospective clinical study

The aim of this clinical study was to evaluate and compare the incidence and intensity of postoperative pain following removal of gutta-percha from root canals using rotary and reciprocating instruments. One hundred and sixty patients scheduled for a non-surgical endodontic retreatment were included for evaluation. Preoperative pain was recorded with using a questionnaire with a 10-cm visual analogical scale (VAS). Endodontic filling material was removed with Reciproc (VDW, Munich, Germany) or ProFile (Dentsply Tulsa Dental Specialties, Tulsa, OK) instruments. Patients then recorded their postoperative pain in a VAS pain scale at 4, 8, 16, 24, 48, and 72 h post-treatment. Results were analyzed using the Mann-Whitney U, Kruskal-Wallis, and Chi-square tests. Multivariate logistic and a multiple regression analysis were used to detect the effect of confounding factors. Results showed a direct relation between the intensity of pre-operative pain and that of postoperative pain (P < .05). No significant differences were observed between the two groups regarding postoperative pain (P > .05) as a qualitative variable. As numerical values, statistically significant differences were found regarding sex and the system used (P < .05). The method for pain evaluation was determinant in postoperative pain findings. Endodontic retreatment preparation with Reciproc results in lower values of postoperative pain compared with ProFile. Women are more susceptible to postoperative pain than are men. One of the most significant contributions of this research is the importance given to the method used for pain evaluation. The present study analyzed postoperative pain resulting from the use of reciprocating or continuous rotary instruments during removal of gutta-percha in retreatment procedures.