The prevalence of dental caries in the first permanent molars among individuals aged 6–18 years: a systematic review and meta-analysis of studies from Asia, Europe, Africa, and Latin America

Dental caries in the first permanent molars, a chronic disease, significantly impairs oral function. However, comprehensive data on its prevalence remain limited. Our study aimed not only to investigate the prevalence of dental caries in the first permanent molars across four regions (Asia, Europe, Africa, and Latin America), but also to provide suggestions for subsequent analysis. Pub Med, web of science, Embase, Scopus, Cochrane library, Wanfang and CNKI database were used to search for studies correlated to the prevalence of dental caries in the first permanent molars among people between 6 and 18 years old, published before 3 January 2026. Meta-analysis was performed using R software. Different effect models (random-effects model or fixed-effect model) were chosen to estimate the pooled prevalence according to the I2 value. The heterogeneity was analyzed by subgroup analysis from perspectives of sample size, publication period, geographic region, World Bank-classified regions (WB region), setting, age, gender, and disease diagnosis. Publication bias was examined using Egger’s test and visualized by the funnel plot. A total of 768,263 eligible subjects were included in 66 studies from Asia, Europe, Africa, and Latin America. The pooled prevalence of dental caries in the first permanent molars was 0.33 (95%CI: 0.28, 0.38). The subgroup analysis showed that the prevalence of dental caries in the first permanent molars among different geographic regions were as follows: Asia: 0.30 (95%CI: 0.26, 0.35); Africa: 0.53 (95%CI: 0.30, 0.74); Europe: 0.51 (95%CI: 0.35, 0.67); Latin America: 0.48 (95%CI: 0.39, 0.56). The prevalence of dental caries in the first permanent molars among different age groups were 0.31 (95%CI: 0.26, 0.38) in children and 0.45 (95%CI: 0.38, 0.53) in adolescents, respectively. Furthermore, statistically significant differences in the prevalence of dental caries were found in subgroup analyses stratified by WB region, sample size, publication year, sex, and disease diagnosis (all p for subgroup difference < 0.05). This study demonstrates a relatively high prevalence of dental caries in the first permanent molars across Asia, Europe, Africa, and Latin America, underscoring the need for sustained clinical and public health focus. However, these findings are not generalizable to North America or Oceania due to the absence of data.