Comparative Assessment of Postoperative Pain After Three Irrigation Techniques in Single-Rooted Teeth With Symptomatic Irreversible Pulpitis and Symptomatic Apical Periodontitis: A Randomized Controlled Trial.

Aim This study aimed to assess the impact of positive pressure, negative pressure (EndoVac), and sonic-activated irrigation (EndoActivator) on postoperative pain with symptomatic irreversible pulpitis and symptomatic apical periodontitis. The hypothesis tested the superiority of negative pressure irrigation in reducing pain and analgesic requirements. Methodology Forty-eight eligible patients meeting inclusion criteria were enrolled, ensuring comprehension through verbal and written patient information sheets. The sample size calculation, based on prior data, determined 14 teeth per group with consideration for potential dropouts, resulting in 16 teeth per group. Inclusion criteria included healthy individuals aged 16-65 years with single-rooted teeth diagnosed with symptomatic irreversible pulpitis and symptomatic apical periodontitis, while exclusion criteria comprised recent analgesic intake, pregnancy, lactation, and specific dental conditions. Participants were allocated to three groups using computer-generated block randomization with allocation concealment via sequentially numbered opaque sealed envelopes. While blinding of the operator was not feasible, patient and assessor blinding was ensured. Preoperative data collection included patient demographics, tooth details, and pain intensity assessed on a Visual Analogue Scale (VAS). Root canal therapy procedures, conducted in two visits, included instrumentation and irrigation using 3% NaOCl across three groups: positive pressure irrigation, negative pressure irrigation, and sonic activation. Postoperative pain and analgesic intake were evaluated using VAS at specific intervals. One assessor tabulated and analyzed all the information. Results Postoperative pain assessments revealed that the EV group experienced the lowest pain levels, followed by the EA and SVN groups, with significant differences observed at six and 24 hours postoperatively (p < 0.05). Analgesic requirements correlated with pain levels, with the SVN group requiring the most analgesics and the EV group the least, highlighting the efficacy of the interventions. Conclusions Negative pressure irrigation (EndoVac) significantly reduced postoperative pain compared to conventional side-vented needle irrigation. These findings enhance understanding and guide evidence-based recommendations for optimizing endodontic procedures and prioritizing patient comfort and outcomes.