Early childhood caries (ECC) remains a major global oral health burden, yet clinical guidance on the optimal timing and frequency of tooth brushing has been inconsistent. This systematic review and meta-analysis ( 32 observational studies; 2000–2024 ) evaluated the association between tooth brushing initiation age, brushing frequency, and ECC risk in children under 6 years. Pooled analyses demonstrated that delayed initiation of tooth brushing was associated with increased ECC risk , becoming statistically significant after exclusion of an outlier ( OR 1.75; 95% CI 1.50–2.03 ).
In parallel, brushing less than twice daily was linked to a more than twofold increase in ECC odds (OR 2.11; p = 0.0052). Despite notable heterogeneity across studies, there was no evidence of publication bias. Overall, the findings support initiating tooth brushing by 12 months of age and maintaining at least…
