Association Between Chromogenic Black Stain and Dental Caries in Children: A Systematic Review and Meta-Analysis.

Objectives: To evaluate the association between chromogenic black stain and dental caries in children, and to estimate the pooled prevalence of BS in pediatric populations. Methods: A systematic search was conducted in PubMed, Web of Science, EMBASE, and the Cochrane Library up to February 2025. Eligible studies included observational studies, clinical trials, and systematic reviews on BS and dental caries in children ≤15 years. Data extraction and quality assessment (Newcastle-Ottawa Scale) were performed independently by two reviewers. Random-effects meta-analyses estimated pooled odds ratios for caries risk and BS prevalence. Results: Fourteen studies met inclusion criteria. Twelve reported an inverse association between BS and caries, one showed no significant relationship, and one was inconclusive. Five studies were included in the meta-analysis, which indicated that children with BS had significantly lower odds of caries (pooled OR = 0.53; 95% CI: 0.36-0.78). The pooled prevalence of BS was 9.4% (95% CI: 6.6-12.2%), with substantial heterogeneity among studies. Conclusions: Black stain in children may be associated with a lower risk of dental caries, although this finding should be interpreted with caution given the limited number of studies and substantial heterogeneity.