Sociodemographic determinants of decayed, missing and filled teeth index among students in Islamic Republic of Iran

Background: Dental caries represent a significant public health concern across all age groups. Knowledge of the decayed, missing and filled teeth index can be instrumental for designing targeted prevention interventions. Aim: To investigate the decayed, missing and filled teeth index among students in Mazandaran Province, Islamic Republic of Iran, and its association with the sociodemographic factors. Methods: Between February and May 2024, we interviewed 1360 12-year-old students in public schools in Mazandaran Province, northern Islamic Republic of Iran. We analysed the data using STATA version 14, used Kolmogorov-Smirnov test and QQ plot to assess normality, ArcGIS 10.8.2 to conduct optimised hotspot analysis, and R for other spatial analyses. P < 0.05 was considered statistically significant. Results: The mean total decayed, missing and filled teeth score was 1.69 ± 2.04, with a caries-free rate of 45.2%. Girls had a significantly higher mean decayed, missing and filled teeth (1.92 ± 0.08) than boys (1.48 ± 0.07) (P < 0.001). Students with unemployed fathers (1.85 ± 1.57 vs. 1.65 ± 2.17; P < 0.001) and those living in rural areas (1.98 ± 2.22 vs. 1.56 ± 1.93; P < 0.001) had higher decayed, missing and filled teeth scores. Students whose parents were illiterate had the lowest prevalence of caries-free teeth, while those whose parents had at least secondary education had the highest prevalence. Conclusion: Despite progress in the prevention of tooth decay, dental caries is still a major problem among 12-year-old students in Mazandaran Province. Gender, parents’ education and occupation, and place of residence are important determinants of dental caries among the students. There is a need to intensify actions to improve oral health among the study population.