AbstractObjectiveTo systematically evaluate randomized controlled trials (RCTs), with at least 6 months of follow‐up, on whether professional mechanical plaque removal (PMPR) including supragingival scaling should be performed prior and separately from subgingival scaling and root planning (SRP) in nonsurgical periodontal therapy (NSPT), in terms of clinical and patient‐reported outcomes (PROs) (CRD42020219759).MethodsThe MEDLINE, EMBASE, CENTRAL, LILACS and Web of Science electronic databases, as well as grey literature sources, were searched by two independent reviewers up to May 2023. The Cochrane Collaboration's Risk of Bias tool (RoB 2.0) was used for quality appraisal and GRADE for assessing the certainty of evidence. Random‐effects pairwise meta‐analyses compared the changes in probing pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BoP) of a stepwise NSPT approach (PMPR prior and separately from SRP) and conventional one‐step NSPT through mean differences (MDs) and associated confidence intervals (95% CI).ResultsTwo RCTs were included, including data of 77 participants with severe periodontitis. One RCT presents high risk of bias and the other has some concerns. No significant differences were found between the stepwise approach and performing both steps simultaneously for any clinical outcomes, with overall very low certainty on evidence. No adverse effects were detected and there was no data on PROs.ConclusionsThere is very‐low certainty evidence of no significant difference on PPD and BoP reductions and CAL gain between supragingival scaling performed prior and separately from SRP and conventional one‐step NSPT.