Effect of occlusal reduction on postendodontic pain: A systematic review and meta-analysis of randomised clinical trials.

The purpose of this systematic review was to assess the effect of occlusal reduction on post-operative pain following root canal treatment and was performed in accordance with the PRISMA statement being registered in the PROSPERO database (CRD42018089941). Two reviewers independently conducted a systematic literature search in the PubMed (MEDLINE), Dentistry & Oral Sciences Source and the Cochrane Library databases. Seven studies were included, of which three were used to perform meta-analysis for 6 days post-operative and the rest for qualitative synthesis. Three studies were assessed as low risk of bias, three as some concern, and one as high risk of bias. Occlusal reduction diminishes the post-operative pain (SMD -1.10 (95%CI -2.06, -0.15) I2  = 96.9%) at 6 days for teeth diagnosed as irreversible pulpitis, and, overall, likely reduces post-operative pain for patients presenting with irreversible pulpitis and/or symptomatic apical periodontitis. Future high-quality clinical trials are needed to better understand the role of occlusal reduction.