Starting toothbrushing at around the age of 1 may be associated with a lower risk of early childhood caries (ECC) in preschool-age children, according to a systematic review published recently in BMC Oral Health.
Additionally, brushing more frequently appears to offer the greatest benefit, the authors wrote.
“The overall evidence suggests that commencing tooth brushing by 12 months of age and brushing at least twice daily may be protective against ECC,” wrote the authors, led by Hesham Mohammed Al-Sharani of the Australian National University (BMC Oral Health, December 30, 2025, Vol. 26, 2006).
To explore the relationship between toothbrushing initiation age and brushing frequency with ECC in children under 6 years old, the researchers conducted an electronic search for observational studies published between 2000 and 2024. The population included healthy children ages 6 months to 6 years, excluding those with conditions affecting dental development, they wrote.
Exposures were defined as brushing initiation before versus after the age of 1 and brushing frequency of at least twice daily versus less than twice daily, allowing comparisons of early versus late initiation and high versus low frequency. The primary outcome was ECC incidence, prevalence, or severity. Of 2,833 records identified, 32 studies met the inclusion criteria.
Multiple studies found that starting toothbrushing by or before the age of 1 was linked to significantly lower ECC incidence or severity, with all comparing early initiation (< 1 year or < 2 years) to later initiation (≥ 1 year or ≥ 2 years). Ten studies were included in the brushing initiation meta-analysis, where late initiation showed a borderline nonsignificant association with ECC risk (odds ratio [OR] = 1.40; 95% confidence interval [CI]: 0.91 to 2.16), they wrote.
Most studies examining brushing frequency consistently reported benefits of brushing at least twice daily in reducing ECC prevalence. Across eight studies comparing high (≥ 2 times/day) versus low (< 2 times/day) brushing frequency, children who brushed less frequently had a substantially higher ECC risk. A random-effects meta-analysis confirmed this association, showing that brushing fewer than twice daily was linked to 2.1-fold higher odds of ECC (OR = 2.11; 95% CI: 1.25 to 3.55).
However, the study had limitations. The included studies were observational, so residual confounding factors could not be ruled out, the authors added.
“The collective direction of evidence aligns with current guidelines advocating early and frequent brushing to prevent early childhood caries,” the authors concluded.
