Disparities in Dental Caries Worldwide Between Rural and Urban Populations Among 12- to 15-Year-Olds: A Systematic Review and Meta-Analysis.

Purpose: This systematic review and meta-analysis aimed to assess and compare dental caries among adolescents aged 12 to 15 years worldwide residing in rural and urban areas. Methods: A systematic search was conducted in PubMed, Scopus, Web of Science, EMBASE, and Google Scholar. Studies reporting decayed, missing, filled teeth (DMFT) and decayed, missing, filled surfaces (DMFS) for permanent teeth scores for both urban and rural adolescents aged 12 to 15 years were included. Risk of bias was assessed using the Newcastle-Ottawa Scale. Meta-analysis was performed using Review Manager 5.3 software using a random-effects model, with standardized mean differences (SMD) and 95 percent confidence intervals (95% CI) calculated. Heterogeneity was assessed using the I² statistic, and certainty of evidence was evaluated using GRADE. Results: Fifty-four cross-sectional studies were included. Pooled analysis revealed significantly higher DMFT/DMFS scores in urban adolescents (SMD equals 0.34, 95% CI equals 0.22 to 0.46; P<0.001), with considerable heterogeneity (I² equals 99%). Subgroup analyses were conducted by geographical region, age group, and study publication period (past decade). Adolescents residing in urban areas exhibited higher dental caries in comparison to their rural counterparts, although regional variations were evident. Conclusions: Based on these findings, there is a need for context-specific oral health policies and tailored preventive strategies to address inequalities in both urban and rural populations aged 12 to 15 years.