Background The use of fluoride-containing dentifrices can reduce the risk of dental caries. The systematic review was conducted to address two research questions: (i) the prevalence and frequency of fluoridated toothpaste use among Nigerian children and adolescents across geographic and demographic settings, and (ii) its association with dental caries prevalence, stratified by location and baseline caries risk.

Methods This systematic review, registered with PROSPERO (CRD42022362116), followed the PRISMA guidelines. A PIO framework was applied to include children and adolescents (6 months–19 years) in Nigeria using fluoridated toothpaste, with caries outcomes measured via dmft/DMFT indices. A comprehensive search of PubMed, Web of Science, Scopus, Embase, AJOL, and Google Scholar was conducted from January 2001 to January 2026, supplemented by reference and grey literature searches. Study selection, data extraction, and risk of bias assessment using an adapted Hoy et al. tool were performed independently by multiple reviewers, with high inter-rater reliability (Kappa=0.90). Data were pooled using a random-effects model, with sensitivity, subgroup, and meta-regression analyses conducted to explore heterogeneity and effect modifiers. Publication bias was assessed using funnel plots and Egger’s test.

Results Of 1,194 identified records, 18 studies (n=12,719 participants) were included. The use of fluoridated toothpaste was widespread (prevalence: 61.9% to 95.8%), yet its association with dental caries varied significantly by location. A meta-analysis of 14 studies indicated a significant 16% reduction in caries odds with fluoridated toothpaste use after removal of an influential outlier (OR = 0.84, 95% CI: 0.71–0.99, p=0.04). Subgroup analyses revealed this protective association was significant in urban and rural settings (p<0.05) but absent in suburban Nigeria. Furthermore, dental caries prevalence and severity (DMFT/dmft) were substantially higher in urban and rural areas, where the association was significant, compared to suburban regions. All studies were assessed as having a low risk of bias, and no significant publication bias was detected.

Conclusion Fluoridated toothpaste is widely used in Nigeria and associated with a reduction in the prevalence of dental caries in Nigeria. It appears the relationship is moderated by residential location, and the DMFT/dmft. Longitudinal studies are needed to explore the interactions between the DMFT/dmft, use of fluoridated toothpaste, and residential location in Nigeria.

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

This research was funded by the Nigerian Institute of Medical Research (grant number NM-ADJGT-22-0082) with a value of ~$260. The funder played no role in the conceptualization and execution of the meta-analysis.

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