Abstract: Objective To investigate the prevalence of dental caries among 3 to 5-year-old children in urban area of Nanjing, detect the caries activity Cariostat value and analyze the relationship between Cariostat value and dental caries. Methods 343 children aged 3 to 5 from a kindergarten in Nanjing were examined by a cross-sectional sampling method. The oral condition of children was examined by two specialists and the Cariostat value was determined. Meanwhile, a questionnaire survey was conducted on children's primary caregivers. Results The prevalence in children aged 3 to 5 was 64.43%; the DMFT was 3.71±4.42; the dmfs was 6.72±10.44; the filling rate was 11.16%, and the Cariostat value was 1.98±0.716. There was a significant difference in Cariostat value between the caries group and the caries-free group. The related factors of Cariostat values were feeding mode within six months of birth (OR breastfeeding=2.069), time of using bottle (OR only before two years old=0.626), mother’s daily smoking or passive smoking (ORweekly=4.785), soft scale index (ORno=0.120, ORcovering tooth surface less than 3=0.438), saliva pH value (OR=0.604), and dfms (OR=1.061). Conclusion The prevalence of dental caries among 3 to 5-year-old children in Nanjing is serious. Therefore, in addition to the treatment of existing dental caries, mother/primary caregivers can also reduce the rate of dental caries by scientific feeding within six months of birth, reducing the time of bottle use, quitting smoking and refusing secondhand smoking.

Key words: 3- to 5-year-old children, dental caries, Cariostat value