Introduction: A systematic review of the evidence on the impact of dental caries on malnutrition risk in children was conducted.
Objectives: To systematically review published evidence pertaining to the effect of dental caries severity and prevalence on risk of wasting or stunting in children.
Methods: Four questions relating to caries of the permanent dentition, primary dentition, early childhood caries (ECC), and severe ECC as a risk factor for undernutrition were set. The target population was children aged 0 to 18 y from any country. Data sources included MEDLINE and Embase. All human epidemiological studies were included. Quality assessment excluded lowest-quality studies. Evidence synthesis by vote counting was depicted using harvest plots. A best available evidence approach was applied to narrative synthesis. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.
Results: Of the 2,690 studies identified, 447 were screened in duplicate; of these, 117 underwent quality assessment, resulting in 46 included studies, of which 38 were included in vote counting (3 quasi-experimental, 1 cohort, 1 case control, and 33 cross-sectional studies). For the permanent dentition, findings were mixed; the balance of data showed no association between caries prevalence (7/11 studies) or severity (8/17 studies) with wasting. For the primary dentition, the balance of data showed a positive association between caries prevalence (10/15 studies) and severity (12/15 studies) with wasting, as well as between-caries prevalence (4/5 studies) and severity (6/6 studies) with stunting. Considering ECC only did not alter this pattern of findings.
Conclusion: The balance of evidence suggests that dental caries in the primary dentition is associated with undernutrition. There is a need for well-designed trials on the impact of caries rehabilitation on growth trajectories of children from low- and middle-income countries and for prospective studies of the impact of caries severity on both stunting and wasting to confirm causality.
Knowledge transfer statement: The results of this study can be used by policy makers when considering the importance of oral health in addressing the United Nations Sustainable Development Goal to end all forms of malnutrition. The findings suggest that dental caries in the primary dentition may impair children's healthy weight gain. The findings indicate that higher-quality data are required to confirm a causal relationship and thus inform funding bodies of the need for research, especially in low- and middle-income countries, to substantiate the current knowledge and inform clear and accurate policy statements.
Keywords: growth; malnutrition; oral health; stunting; systematic review; thinness.