The present study was conducted to assess relationship between drinking water fluoride levels and dental caries among 12 years old school children of 2 districts of Ulaanbaatar city, Mongolia. A cross-sectional analytical study was conducted on 533 school children aged 12 years, selected from 6 schools of 2 districts of Ulaanbaatar city. 533 children were divided into 2 groups according to the fluoride concentration of the waters. The all children were examined oral examination, dental caries was assessed by the DMF-T index. The result of the present study revealed that the caries prevalence in the study population was about 68,9%, and mean DMF-T was 3.05. Water fluoride concentration was highest in Khan-Uul district with 0.622ppm. There was highest prevalence of caries in children who consume water from filtration system in both districts.

The present study was conducted to assess relationship between drinking water fluoride levels and dental caries among 12 years old school children of 2 districts of Ulaanbaatar city, Mongolia.A cross-sectional analytical study was conducted on 533 school children aged 12 years, selected from 6 schools of 2 districts of Ulaanbaatar city. 533 children were divided into 2 groups according to the fluoride concentration of the waters. The all children were examined oral examination, dental caries was assessed by the DMF-T index.The result of the present study revealed that the caries prevalence in the study population was about 68,9%, and mean DMF-T was 3.05. Water fluoride concentration was highest in Khan-Uul district with 0.622ppm.There was highest prevalence of caries in children who consume water from filtration system in both districts.