Abstract: Objective To describe the caries status and associated factors in students aged 12 to 15 years old in Jiangsu Province and to provide reliable evidence for health service of caries prevention in the future. Methods Referring to WHO Oral Health Surveys -Basic Methods (Fifth Edition), a sample of 3914 students aged 12 to 15 years old were drawn by the method of multistage, stratified, equal capacity and simple random. Subjects were divided into four different age groups (aged 12，13，14 and 15)，with 978，986，978 and 972 students in each group. The dental caries were recorded and the questionnaire was filled. And then the mean DMFT was analyzed by Kruskal-Wallis H Test, and the prevalence, the filling rate and the pit and fissure sealant rate were analyzed by Chi-squared Test. Meanwhile, the associated factors were analyzed by Binary logistic analysis. Results The permanent tooth caries prevalence in the 12- to 15-year-old was 34.98% and the mean DMFT was 0.69, which were both higher in females than males and made a significant difference in gender (P＜0.001). The filling percentage of caries of students aged 12 to 15 years old was only 17.53%, and that of male was higher than that of female in rural areas(P=0.039）. What’s more, the tooth position of the highest permanent tooth caries prevalence was the first permanent molar. The living area, gender and the frequency of having sweet cakes or s were the risk factors of the permanent tooth caries. Conclusion Due to the high caries prevalence of students in Jiangsu Province, good oral health behaviors should be encouraged and preventive measures in high-risk groups should be carried out. Public health measures and oral health education are also needed to control the risk factors of caries.

Key words: permanent tooth , caries, epidemiological survey, associated factors, Jiangsu Province