Effect of Occlusal Reduction on Postoperative Pain in Symptomatic Irreversible Pulpitis and Apical Periodontitis: A Systematic Review of Randomized Clinical Trials

Objectives: Acute dental pain due to symptomatic irreversible pulpitis associated with symptomatic apical periodontitis represents one of the most challenging emergencies in endodontics. Occlusal reduction has traditionally been proposed as an adjunctive procedure to relieve postoperative pain following root canal treatment. This systematic review aimed to evaluate the effectiveness of occlusal reduction in reducing postoperative pain intensity in patients with symptomatic irreversible pulpitis and apical periodontitis. Materials and Methods: A comprehensive electronic search was conducted in PubMed, ScienceDirect, and Google Scholar for studies published between 2012 and 2022, using the keywords occlusal reduction, symptomatic irreversible pulpitis, and symptomatic apical periodontitis. Boolean operators were applied. Inclusion criteria were randomized or prospective clinical trials published in English or French that evaluated the effect of occlusal reduction in endodontically treated teeth diagnosed with symptomatic irreversible pulpitis, with or without apical periodontitis. Five studies met the eligibility criteria and were included in the review. Statistical Analysis: Postoperative pain intensity, assessed using Visual Analog Scale (VAS) or Numeric Rating Scale (NRS) at different time intervals, and analgesic or placebo consumption were recorded. Due to heterogeneity in study designs and outcome measures, a qualitative synthesis was performed. Results: Five clinical trials published between 2013 and 2021, involving a total of 499 patients, were analyzed. Two studies reported a significant reduction in postoperative pain during the first 12 - 24 hours following occlusal reduction compared with control groups, whereas three studies found no statistically significant difference between groups. Analgesic consumption did not differ significantly across the included studies. Variability in methodology, tooth type, instrumentation techniques, and evaluation intervals may account for the conflicting results. Conclusions: Current evidence suggests that occlusal reduction may provide limited short-term benefits in reducing postoperative pain in endodontically treated teeth with symptomatic irreversible pulpitis and apical periodontitis, particularly within the first 12 - 24 hours. However, its overall effectiveness remains inconsistent, and occlusal reduction should not be recommended as a routine adjunctive procedure. Further well-designed randomized controlled trials are required to clarify its clinical relevance.