Effect of occlusal reduction on post-operative pain of symptomatic and asymptomatic molar teeth.

Objective: This study aimed to compare the intensity of post-operative pain after single-visit root canal treatment of symptomatic or asymptomatic teeth following occlusal reduction.

Methods: A total of 140 symptomatic or asymptomatic patients in need of root canal therapy were registered in this prospective, single-centre, single-blind, randomised clinical trial. For all patients, root canal treatment was carried out in a single visit, and the teeth were restored using composite resin. The patients were randomly allocated into four treatment groups, two of which included occlusal reduction while two treatments left the occlusional contacts intact. Patients' pain were assessed using a 0-3 verbal rate scale 1, 3, and 7 days following root canal treatment. The pain incidence and intensity were compared using the chi-square and Fisher's exact tests.

Results: Overall, the post-operative pain intensity was low. Symptomatic individuals had significantly more discomfort at day 1 post-operatively compared to asymptomatic patients (p < 0.008). The pain incidence significantly decreased over time for symptomatic patients. When compared to asymptomatic patients without occlusal reduction, symptomatic patients with occlusal reduction had a greater pain incidence at day 3 (p < 0.011). For other time intervals, no significant differences in post-operative pain incidence or intensity were found.

Conclusion: Single-visit root canal treatments involving occlusal reduction in both symptomatic or asymptomatic molars had no significant effect on post-operative pain.