OR18 - Randomized Clinical Trial Evaluating Post-Operative Pain After the Use of Gentle Wave or Laser-Assisted Irrigation in Teeth with Pulp Necrosis and Symptomatic Apical Periodontitis

Objective: Microbial antigens such a lipopolysaccharides and lipoteichoic acid have been correlated with pre-operative and post-operative pain levels. Unfortunately, substantial amounts of residual antigens can still be detected in root canals after the use of traditional chemomechanical preparation with needle irrigation. Adjuncts in irrigation, such as Gentle Wave System (GWS) and Laser-Assisted irrigation (LAI), aim to increase disinfection and remove these antigens. Thus, we hypothesized that the use of GWS and LAI results in reduced post-operative discomfort compared to traditional needle irrigation.

Methods: Patients with a tooth diagnosed with pulp necrosis and symptomatic apical periodontitis were randomized into one of the 3 irrigation treatment arms: 1) GWS; 2) LAI or 3) needle. Following the treatment completion, patients received text-messaging questionnaires at 6, 24, and 72 hours after completion of treatment. The pain level was recorded using the NS-11 scale, and statistical analysis was evaluated using one-way ANOVA and Bonferroni’s post hoc test.

Results: There was a significant reduction in pre-operative pain observed in all treatment groups, with a moderate rebound increase in 24 hours and 72 hours following treatment. GWS and LAI reduced post-operative pain compared to needle irrigation at 24 and 72 hours.

Conclusion: Collectively, these results support the use of adjunct irrigation to reduce post-operative pain, possibly due to the increased disinfection and removal of antigens.