Objectives: The aims of this study were to investigate the dental caries experience among 1-5 year-old children in the two areas of Ulaanbaatar city, and to examine the relationship of dental caries experience with socioeconomic status, eating behaviors, oral hygiene habits, dental plaque accumulation and Mutans Streptococci level.
Methods: In 2004/2005, 670 children from the two areas were examined and a questionnaire survey was conducted. Mutans streptococci (MS) levels in the children's and mothers' dental plaque were evaluated using Dentocult SM.
Results: Dental caries prevalence (72%) and mean dmft (4.4) were very high in both areas, however, children in the central area showed higher caries severity than those in the suburban area in 3-5-year-olds (p < 0.05). Higher family income and education level of the mothers were significantly associated with children's higher caries experience. Furthermore, dental caries showed a significant positive relationship with sweets intake and a negative relationship with tooth brushing habits of the children. The children's caries experience was significantly and positively associated with modified debris index (m-DI) scores, and the MS levels in their own and their mothers' dental plaque. Area, sweets intake, prolonged breastfeeding, and high MS level in the dental plaque resulted in significant odds ratios for the development of caries.
Conclusions: The prevalence of dental caries amongst 1-5 year-old children in Ulaanbaatar City, Mongolia was found to be high and was associated with socioeconomic, demographic and behavioural factors.