Title: The Consequences of Severe Early Childhood Caries on Early Childhood Weight
Description: The 2000 U.S. Surgeon General’s report identified oral health as a priority health concern and recognized that oral health is integral to general health. A serious and widespread oral health problem is dental caries, a chronic infectious, transmissible disease of the oral cavity. While adverse short-term consequences of dental caries such as pain and further infection are well known and long-established, long-term consequences are not as generally recognized and accepted. However, evidence for these short-term consequences has spurred discussion of potential long-term consequences as well; in particular, negative effects on early childhood weight. An established literature examining the hypothesis that severe early childhood caries has an adverse effect on early childhood weight suggests that severe caries may lead to less attained weight and less weight gain. Additionally, the literature posits hypotheses about potential causal pathways through chronic inflammation, diet, and/or sleep disturbances, which the literature claims stem from pain and infection.

However, there are no studies that formally conduct meditational analyses and furthermore, the present body of literature does not even adequately test the main effect because the evidence base suffers from methodological issues that make it difficult to rule out alternative explanations for the positive associations that have been found. The overarching goal of this dissertation is to better understand the relationship between oral health and general health by examining if a common oral disease, severe early childhood caries, a specific variant of dental caries, has adverse effects on early childhood weight using a causal framework perspective to address the limitations and gaps in the literature. This dissertation consists of three papers that examine the theory that severe caries negatively affects weight attainment and weight gain in children. The first paper, a systematic review, synthesizes and critically appraises the literature on the negative effects of severe early childhood caries on early childhood weight to identify what is known about the relationship and the gaps in the literature to inform the subsequent empirical tests of the hypothesis.

The second and third papers empirically test the hypothesis. The second paper examines if severe early childhood caries leads to less attained weight and less weight gain in children and if treatment for severe caries mitigates the problem. The third paper will examine hypotheses about mediation of the association. The systematic review shows that despite reasonable consistency of findings across the literature examining the negative effect of severe early childhood caries on early childhood weight, the studies are not conclusive due to the possibility of reverse causation and the potential for residual confounding. The findings in paper 2 only partially support the a priori hypotheses, as associations were not consistent across different comparison groups in the analysis. The mediation hypotheses tested in paper 3 were also not fully supported due to null findings in a link within the causal pathway. Future studies should attempt to build on the findings of this longitudinal examination of the hypothesis by directly addressing the issues identified in the literature review, examining gradations of caries exposure, and improving measurement of the mediators.