The Prevalence of Dental Caries and Related Indices among Schoolchildren Aged 6–12 Years in Narathiwat Province, Thailand: A Comparative Study by Gender and Age

Background: Dental caries is a major public health issue among schoolchildren, affecting quality of life and academic performance. This study compared the prevalence and indices of dental caries—Decayed and Filled for Primary Teeth (dft), Decayed, Missing, and Filled for Permanent Teeth (DMFT), and the Significant Caries Index (SiC)—between male and female children aged 6–12 years in Rueso District, Narathiwat Province, Thailand.Methods: This cross-sectional study was conducted from March 2024 to January 2025 in Rueso District, Narathiwat province, Thailand. Data from 4630 children were obtained from the Provincial Health Data Center using oral health survey records. Caries prevalence was assessed using descriptive statistics. Gender- and age-related differences were analyzed with the Mann– Whitney U and Kruskal–Wallis tests, with significance set at P<0.05.Results: Primary caries was present in male children (51.27%), with significant differences compared with female ones in the dft index (P<0.001) and SiC (dft) (P<0.001). Furthermore, the prevalence of permanent caries was higher in female children (52.69%), with significant differences in DMFT (P<0.001) and SiC (DMFT) (P<0.001) compared with male ones. Age group comparisons revealed significant differences in the dft index (P<0.001), DMFT index (P<0.001), SiC (dft) (P<0.001), and SiC (DMFT) (P<0.001).Conclusions: Significant gender- and age-related differences were observed in dft, DMFT, SiC (dft), and SiC (DMFT). SiC values highlighted the disproportionate burden of caries in specific subgroups. Effective dental health strategies should be tailored to the influence of age and gender on these indices.