Supplementary Material for: Association between Dental Caries and BMI in Children: A Systematic Review and Meta-Analysis

Research on the association between dental caries and body mass index (BMI) in children has shown contradictory results; thus we aimed to examine the association between dental caries and the full range of BMI classes among children. We comprehensively searched PubMed, Embase, and the Cochrane Library for studies published prior to March 2017. Articles comparing dental caries among the full range of BMI classes for children below 18 years of both genders were included. Fourteen studies were eligible for this study. Basic information - i.e., first author, published year, study design, country, sample size, age, type of dental caries index and BMI, main results and conclusions, and means and standard deviations of the dental caries indexes used - was pooled. The weighted mean differences and corresponding 95% confidence intervals for dental caries between children with abnormal weight and those with normal weight were analyzed. Generally, no significant differences in caries were found between any abnormal-weight group and the normal-weight group for both primary and permanent teeth. Sensitivity analyses showed that the obese group had more caries than the normal-weight group in their primary teeth. Significantly more caries was found among the overweight and obese children in both primary and permanent teeth in high-income countries, but not in low- and middle-income countries. We recommend that further studies use suitable sample sizes, unify the criteria for BMI categorization and the dental caries index, and investigate the confounding factors that might influence dental caries and BMI.针对儿童龋齿（dental caries）与体重指数（Body Mass Index, BMI）之间关联的既往研究结果存在矛盾，因此本研究旨在探讨儿童龋齿与全类别体重指数之间的关联。我们系统性检索了PubMed、Embase及Cochrane图书馆，收集2017年3月之前发表的相关研究。纳入符合以下标准的文献：针对18岁以下不同性别儿童，对比其全类别体重指数与龋齿情况的研究。本研究最终纳入14项符合标准的研究。我们对各项研究的基础信息进行了汇总，涵盖第一作者、发表年份、研究设计、研究国家、样本量、受试者年龄、龋齿指数与体重指数的类型、主要研究结果与结论，以及所用龋齿指数的均值与标准差。我们分析了体重异常儿童与体重正常儿童的龋齿情况的加权均数差及其对应的95%置信区间。总体而言，无论乳牙还是恒牙，各类体重异常组与体重正常组的龋齿情况均无显著差异。敏感性分析结果显示，肥胖组儿童的乳牙龋齿情况较体重正常组更为严重。在高收入国家中，超重与肥胖儿童的乳牙及恒牙龋齿情况均显著多于体重正常儿童，但这一关联在低收入与中等收入国家中并未观察到。我们建议后续研究应采用合适的样本量，统一体重指数分类标准与龋齿指数标准，并探究可能影响龋齿与体重指数的混杂因素。