Oral hygiene protocols reduce the severity and incidence of oral mucositis during antineoplastic treatment: a systematic review and meta-analysis of randomized and non-randomized clinical trials.

Objective: The objective of this systematic review was to determine whether oral and dental hygiene protocols (DHPs) reduce the incidence and severity of oral mucositis (OM) during antineoplastic treatment.
Materials and Methods: This PROSPERO-registered systematic review (CRD42021295322) was based on searches of publicly accessible databases, including PubMed, Scopus, Web of Science, LILACS, EBSCOhost, LIVIVO, Embase, and gray literature (Google Scholar, ProQuest, and Energy) until December 2021. Twenty-five articles from these searches and 14 articles retrieved from the references therein were evaluated in this systematic review and meta-analysis. The risk of bias (RoB) was assessed using RoB-2 and ROBINS-I for randomized (RCT) and non-randomized (n-RCT) clinical trials, respectively. A meta-analysis was performed on RCTs and n-RCTs in two subgroups to evaluate oral mouth rinses or DHP. GRADE-pro was used to assess the degree of certainty of the evidence.
Results: Of the 3367 articles retrieved, 25 RCTs and 14 n-RCTs involving 2109 and 754 patients, respectively, were included in the analyses. RoB was low for RCTs and moderate-to-very severe for n-RCTs. High heterogeneity and publication RoB were identified. In RCTs, mouth rinses (p = 0.830) and DHP (p = 0.100) did not reduce the incidence of OM. However, mouth rinses strongly reduced the severity of OM (p < 0.001; Cohen's d =  - 1.87, 95% confidence interval [CI] =  - 2.49 to - 1.24). In non-RCTs, mouth rinses (p < 0.001) and DHP (p < 0.001) reduced the relative risk of OM 0.38 (95% CI = 0.24 to 0.59) and 0.64 (95% CI = 0.53 to 0.70) times, respectively. In addition, DHP strongly reduced OM severity (Cohen's d =  - 0.81, 95% CI =  - 1.03 to - 0.59). GRADE-pro showed high certainty of OM severity and incidence in RCTs and non-RCTs, respectively, and low (OM incidence in RCTs) to very low (OM severity in non-RCTs) certainty in other outcomes.
Conclusion: DHPs strongly reduce the severity and moderately reduce the incidence of OM. However, further studies with low heterogeneity are needed to validate these findings.
(© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)