RESUMO
OBJECTIVES: Adherence to the daily use of dental floss in childhood is recommended by various international health institutions/organizations. This systematic review (PROSPERO number CRD42020205232) aims to evaluate the prevalence of dental floss use in deciduous dentition. MATERIALS AND METHODS: A systematic review was conducted in six databases (B-on, Cochrane Library, PubMed, Scielo, Science Direct and Web of Science) up to December 2020. The CoCoPop mnemonic allowed for obtaining 2333 articles and resulted in the inclusion of 7 observational studies that evaluated the prevalence of dental floss use (primary outcome) in children up to 6 years old. The Joanna Briggs Institute critical appraisal checklist was used to evaluate the risk of bias, showing that most articles presented good quality. Meta-analyses were performed using the proportion of dental floss use (yes or once/day) and the random effects model. RESULTS: The meta-analysis showed a prevalence of dental floss use of only 12.60% (95% CI: 7.69%-18.52%) based on studies with high heterogeneity of results (I2 = 94.75%; 95% CI: 91.44%-96.78%). Six of the seven studies showed that more than 70% of children never used dental floss. CONCLUSIONS: A low prevalence of dental floss use was observed in children up to 6 years old. Given the diversity of evaluating the use of dental floss, different options should be the target of standardization in future studies.