Abstract: To study the relationship of birth weight and current body mass index（BMI） with dental caries in 5-year-old children in Shanghai. Methods　Oral examinations were performed in 4925 5-year-old children. The caries status of deciduous teeth were recorded. Birth weight and current BMI were collected through self-administrated questionnaires from children′s parents. After 1204 children with missing data were excluded，a total of 3721 children were included in the analysis. According to birth weight，all the subjects were divided into 3 groups：< 2500 g group，2500 - < 4000 g group and ≥ 4000 g group. According to current BMI，all the above mentioned groups were subdivided into 3 groups：low BMI（marasmus，BMI < P5）subgroup，normal BMI（normal body weight，P5 ≤ BMI ≤ P85）subgroup and high BMI（overweight or obesity，BMI > P85）subgroup. The relationship of birth weight and current BMI with caries was analyzed. Results　The prevalence of caries in 3721 children was 53.86%，and the mean decayed，missing and filled teeth（dmft）were 2.38 ± 3.33. In children with birth weight of < 2500 g，2500 - < 4000 g and ≥ 4000 g，the prevalence of caries was 49.65%，53.55% and 59.93%，dmft being 2.14 ± 3.13，2.37 ± 3.33，2.62 ± 3.36. The prevalence of caries of ≥ 4000g group was significantly higher than that of 2500 - < 4000 g group and that of < 2500 g group（χ2 = 5.05，4.58；both P < 0.05）. Among the children with birth weight ≥ 4000g and nomal BMI，the prevalence of caries （61.21%） was significantly higher than that with birth weight 2500 - < 4000 g and normal or high BMI （53.61%，51.52%），and it was also higher than that with birth weight < 2500 g and normal BMI （49.56%） （χ2 = 4.61，5.65，4.10；all P < 0.05）. Conclusion　The prevalence of caries of ≥ 4000g group was high in 5-year-old children in Shanghai. The prevalence of caries of 5-year-old children with normal BMI and birth weight ≥ 4000 g was significantly higher than the children with normal birth weight （2500 - < 4000 g） and high current BMI. High birth weight may be a risk factor for caries.

Key words: birth weight；body mass index, BMI；caries

摘要： 目的　研究上海市5岁儿童出生体重、现身体质量指数（body mass index，BMI）与龋病的关系。方法　于2017年在上海市随机抽取4925名5岁儿童，开展口腔检查，并记录患龋情况。通过对家长的问卷调查获取儿童的出生体重、现BMI信息。排除1204名数据缺失儿童，共3721名儿童纳入本研究。根据出生体重将所有儿童分为低出生体重组（< 2500 g）、正常出生体重组（2500 ~ < 4000 g）和高出生体重组（≥ 4000 g），再根据现BMI将各组儿童分为消瘦的低BMI亚组（BMI < P5）、正常BMI亚组（P5 ≤ BMI ≤ P85）和超重/肥胖的高BMI亚组（BMI > P85），分析出生体重、现BMI与龋病的相关性。结果　完成检查的3721名儿童，其患龋率为53.86%，龋失补牙数（dmft）为2.38 ± 3.33。低出生体重组、正常出生体重组和高出生体重组的患龋率分别为49.65%、53.55%和59.93%，dmft分别为2.14 ± 3.13、2.37 ± 3.33、2.62 ± 3.36。高出生体重组的患龋率显著高于正常出生体重组及低出生体重组，差异均有统计学意义（χ2值分别为5.05、4.58，均P < 0.05）。高出生体重组正常BMI亚组的患龋率（61.21%）显著高于正常出生体重组的正常BMI亚组（53.61%）和高BMI亚组（51.52%），也高于低出生体重组正常BMI亚组（49.56%），差异均有统计学意义（χ2值分别为4.61、5.65、4.10，均P < 0.05）。结论　高出生体重（≥ 4000 g）的上海市5岁儿童患龋率较高。高出生体重、现BMI正常的上海市5岁儿童患龋率仍要高于出生体重正常（2500 ~ < 4000 g）而现BMI高的儿童。高出生体重可能是儿童龋病的危险因素。

关键词: 出生体重, 身体质量指数, 龋病