Abstract: Objective To investigate the prevalence of dental caries among children aged 2-4 years in Tongzhou District, Beijing and explore its influencing factors. Methods Physical examination records and birth information of children with full-term birth （37 weeks ≤ gestational week<42 weeks） from January 1, 2016 to December 31, 2017 were collected from the maternal and child health information system in Tongzhou District. The prevalence of dental caries was calculated, and multivariate logistic regression was used to determine factors influencing dental caries. Results A total of 12 555 children aged 2-4 years with full term were included. Of the participants, 51. 2% were boys, most （75. 1%） were aged 3 years, and 70. 2% had at least one parent’s domicile registered in Beijing. The overall prevalence rate of dental caries was 23. 7%. The prevalence rates of dental caries were 16. 9%, 25. 2%, and 48. 1% for children aged 2, 3, and 4 years, respectively, showing an upward trend with the increase of children's age （P <0. 01）. The binary logistic regression analysis showed that the children with increased age （OR_{3 years old}=1. 67; OR_{4 years old=}4. 58） and whose parents’ domiciles were registered in other places （OR=1. 13） had higher risks of dental caries. Conclusion The prevalence of dental caries was high for children aged 2-4 years in Tongzhou District, Beijing. The risks of dental caries were higher for the children with the increase of age and whose parents’ domiciles were registered in other places. Attention should be paid to the occurrence of dental caries in preschool children, and the oral health of preschool children should be monitored.

Key words: Children, Dental caries, Influencing factors