Abstract: Objective    To analyze the caries status and related risk factors of 3-year-old children in Shanghai，and to evaluate the clinical effect of grading management of caries based on risk assessment. Methods    A total of 1989 3-year-old children from 28 kindergartens in 4 districts of Shanghai in 2018 were randomly divided into experimental group（986 children）and control group（1003 children）by random sampling. With reference to the caries-risk assessment tool （CAT） proposed by American Association of Pediatric Dentistry （AAPD），through the questionnaire survey in combination with clinical examination，children tested were divided into high，medium and low risk grade；intervention management was performed in experimental group with reference to the CAT，and the control group received conventional project management according to the basic public health services in Shanghai. After 1 year of intervention，oral health examinations were made and risk levels were reassessed for both groups of children. Results    （1）A total of 1848 children completed the survey in 2018，including 929 in the experimental group and 919 in the control group. The total caries incidence was 28.0%：26.8% in the experimental group and 29.1% in the control group. The proportion of children at high risk was 56.3% in the experimental group and 59.3% in the control group. After 1 year of intervention management （in 2019），all subjects were followed up. After eliminating incomplete data，a total of 1320 children were included with effective data，including 659 in the experimental group and 661 in the control group. The total prevalence of caries was 35.5%：32.0% in the experimental group and 39.1% in the control group. The incidence of caries was 11.9% and 15.9%，respectively，and the difference was statistically significant （χ2 = 4.22，P < 0.05）. （2）After 1 year of intervention，the high risk level of children in the experimental group and the control group decreased by 14.0% and 12.4%，respectively，and the difference was not statistically significant （χ2 = 0.41，P > 0.05）. The medium risk level of children in two groups decreased by 3.7% and 2.2%，respectively，and the difference was not statistically significant（χ2 = 3.21，P > 0.05）. In the experimental group and the control group，the number of children with low risk level increased by 17.7% and 14.6%，respectively，and the difference was statistically significant （χ2 = 7.29，P < 0.05）. （3）Logistic regression analysis showed that eating sweets < 3 times/d，mothers without caries and eating sweets after brushing before going to bed were the protective factors for high-risk children in the experimental group （P < 0.05），and not having regular professional oral examination was the risk factor （P < 0.05）. Helping children brush their teeth，using fluoride toothpaste and visiting an oral doctor within 6 months were the protective factors for high-risk children in the control group （P < 0.05），while artificial feeding within 6 months and having sweet drinks once a day were the risk factors （P < 0.05）. Conclusion　The incidence of caries in children′s deciduous teeth increases with the increase of age. The use of fluoride toothpaste，regular fluoride application，oral examination and mother being without caries are the protective factors of high-risk children. The application of grading management of caries in children based on risk assessment can reduce the incidence of caries in deciduous teeth and obtain better clinical effect.

Key words: deciduous teeth, caries, risk factors, grading management

摘要： 目的    分析上海市3岁儿童患龋情况及其相关危险因素，评价基于风险评估的龋病分级管理临床效果。方法    采用随机抽样的方法，抽取2018年上海市4个区28家幼儿园3岁儿童1989名，随机分成试验组（986名）和对照组（1003名）。参照美国儿童牙医协会（American Association of Pediatric Dentistry，AAPD）提出的龋病风险评估工具（caries-risk assessment tool，CAT），通过问卷调查结合临床检查，将受检儿童分为高、中、低风险等级，试验组参照CAT进行干预管理，对照组按照上海市基本公共卫生服务项目管理。干预管理1年后，对两组儿童进行口腔健康检查和风险等级的再评估。结果    （1）2018年共1848名儿童完成调查，其中试验组929名，对照组919名。总患龋率为28.0%，试验组和对照组患龋率分别为26.8%、29.1%。试验组高风险儿童比例为56.3%，对照组为59.3%。干预管理1年后（2019年），对所有研究对象进行随访，剔除不完整数据后，共纳入1320名儿童的有效数据，其中试验组659名，对照组661名。总患龋率为35.5%，试验组和对照组患龋率分别为32.0%、39.1%；龋病发生率分别为11.9%、15.9%，其差异具有统计学意义（χ2 = 4.22，P < 0.05）。（2）干预管理1年后，试验组和对照组高风险等级儿童分别降低了14.0%、12.4%，但其差异无统计学意义（χ2 = 0.41，P  > 0.05）；试验组和对照组中风险等级儿童分别降低了3.7%、2.2%，其差异无统计学意义（χ2 = 3.21，P  > 0.05）；试验组和对照组低风险等级儿童分别增加了17.7%、14.6%，其差异有统计学意义（χ2 = 7.29，P < 0.05）。（3）logistic回归分析显示，进食甜食< 3次/ d、母亲未患龋、睡前刷牙后未进食甜食是试验组龋病高风险儿童的保护因素（P < 0.05），未定期进行专业口腔检查是危险因素（P < 0.05）。帮助孩子刷牙、使用含氟牙膏、6个月内去看过口腔医生是对照组龋病高风险儿童的保护因素（P < 0.05），出生6个月内人工喂养、进食甜饮料1次/ d是危险因素（P < 0.05）。结论    儿童乳牙患龋率随着年龄的增长而增高，使用含氟牙膏刷牙、定期涂氟、口腔检查、母亲未患龋是龋病高风险儿童的保护因素。应用基于风险评估的儿童龋病分级管理可降低乳牙龋病发生率，获得较好的临床效果。

关键词: 乳牙, 龋病, 危险因素, 分级管理