Background The risk of SARS-COV-2 transmission is relatively high during dental procedures. A study was conducted to investigate the effects of mouthwashes on SARS-COV-2 viral load reduction in the oral cavity. Methods A systematic search was performed in PubMed, EMBASE, Scopus, Web of Science, and Cochrane library for relevant studies up to 20 July, 2022. Randomized and non-randomized clinical trial and quasi-experimental studies evaluating patients with Covid-19 infection (patients) who used mouthwashes (intervention) compared to the same patients before using the mouthwash (comparison) for reducing the SARS-COV-2 load or increasing the cycle threshold (Ct) value (outcome) were searched according to PICO components. Three independent reviewers conducted literature screening and data extraction. The Modified Downs and Black checklist was used for quality assessment. A meta-analysis was performed with a random effects model in the Revman 5.4.1software using the mean difference (MD) of cycle threshold (Ct) values. Results Of 1653 articles, 9 with a high methodological quality were included. A meta-analysis indicated that 1% Povidone-iodine (PVP-I) was an effective mouthwash for reducing the SARS-COV-2 viral load [MD 3.61 (95% confidence interval 1.03, 6.19)]. Cetylpyridinium chloride (CPC) [MD 0.61 (95% confidence interval -1.03, 2.25)] and Chlorhexidine gluconate (CHX) [MD -0.04 95% confidence interval (-1.20, 1.12)] were not effective against SARS-COV-2. Conclusion Using mouthwashes containing PVP-I may be recommended for reducing the SARS-COV-2 viral load in the oral cavity of patients before and during dental procedures, while the evidence is not sufficient for such effects for CPC and CHX-containing mouthwashes.

BackgroundOral health literacy within the construct of health literacy may be instrumental in decreasing oral health disparities and promoting oral health. Even though current research links oral health literacy to oral health knowledge and education, the impact of educational intervention on oral health literacy remains controversial. We aimed to identify effective health education interventions delivered with a focus on oral health literacy.MethodsAn electronic systematic search in PubMed, Scopus, Web of Science and Cochrane library and gray literatue was performed for relevant studies (1995-2021). Experimental study designs of randomized controlled trials, non-randomized controlled trials, and quasi-experimental studies in which adults aged 18 years or older, male, or female (participants) trained under a health education intervention (intervention) were compared with those with no health education or within the usual care parameters (comparison). An assessment of oral health literacy levels (outcome) were included according to the PICO question. The search was conducted by applying filters for the title, abstract and methodological quality of the data, and English language. Study screening, extraction and critical appraisal was performed by two independent reviewers. Data was extracted from the included studies whereas a meta-analysis was not possible since findings were mostly presented as a narrative format.ResultsEight studies out of the 2783 potentially eligible articles met the selection criteria for this systematic review. The aim of interventions in these studies was 1) improving oral health literacy as the first outcome or 2) improving oral health behavior and oral health skills as the first outcome and assessing oral health literacy as the second outcome. The strength of evidence from the reviewed articles was high and there was an enormous heterogeneity in the study design, OHL measurement instruments and outcomes measure. Interventions were considerably effective in improving oral health literacy.ConclusionHealth education that is tailored to the needs and addresses patients’ barrier to care can improve their oral health literacy level.