Abstract: Abstract: Objective To know the caries rate and mean dmft (dynamical mean-field theory) in children aged 3-15 in Minhang district during 2010-2014 school years, and to find out the age and tooth of high caries incidence. Method From September 2010 to August 2015, 3-15 year-old children in public kindergarten, primary and secondary schools in Minhang district were examined to obtain the baseline data and establish their personal oral health record. The result was analyzed by SPSS20.0 software package. Results During 2010-2014 school years, the caries rate and mean dmft of kindergarten students and pupils demonstrated no tendency, but leveling off (P>0.05). The prevalence rate of caries in kindergarten students was about 50%, and that in pupils was about 60%. The caries rate and mean dmft of middle school students were declined year by year with the minimum value in the 2014 school year, when the caries rate was 28.57% and the mean dmft was 1.14, which were significantly lower than these of kindergarten students and pupils (P<0.01). As far as the grade was concerned, the prevalence of caries and the mean dmft of children aged 3-8 increased with age, those of children aged 9-12 declined with age, but the caries rate of children aged 13-15 declined, and the mean dmft increased slowly with age. Conclusion For kindergarten students and pupils, the prevention of intervention of dental caries is the key; for children under 8 years old, the main focus rests in the prevention of dental caries in deciduous teeth; for children above 8 years old, the prevention and early intervention of dental caries in the first molar are particularly important.

Key words: Caries, 　prevalence proportion rate, mean　dmft