Incidence of post-obturation pain after single-visit versus multiple-visit non-surgical endodontic treatments

Background: Post-obturation pain is frustrating to both patients and dentists. Its incidence may change with the use of contemporary endodontic techniques. This randomised clinical trial aims to compare the incidence of post-obturation pain at one and seven days after single-visit and multiple-visit non-surgical endodontic treatments. Methods: Patients who required primary endodontic treatment in the two clinical trial centres in Hong Kong (HK) and in Beijing (PK) were recruited. Three HK dentists and three PK dentists performed endodontic treatments on 567 teeth using the same procedures and materials, either in a single visit or over multiple visits, using either core carrier or cold lateral condensation for obturation. Results: The attrition rate was 5.1 %, and a total of 538 teeth were evaluated. Among these teeth, 232 (43 %) were operated in HK, 275 (51 %) were treated in a single visit, and 234 (43 %) were treated using core carrier obturation. Logistic regression analysis showed that teeth with apical periodontitis (OR = 0.35, 95 % CI = 0.21-0.57, p < 0.01) and less pre-operative pain (OR = 1.10, 95 % CI = 1.03-1.18, p < 0.01) had lower incidences of post-obturation pain after one day. The incidences of post-obturation pain after one day for single-visit and multiple-visit treatments were 24.7 % (68 of 275) and 33.5 % (88 of 263), respectively (p = 0.50). The incidences of post-obturation pain after seven days for single-visit and multiple-visit treatments were 4.0 % (11 of 275) and 5.3 % (14 of 263), respectively (p = 0.47). Conclusions: There was no significant difference in the incidences of post-obturation pain after one day and seven days with single-visit or multiple-visit endodontic treatments.