Diet is a contributory factor to both obesity and dental caries and a number of studies have linked these two global public health problems. The aim of this systematic review and meta-analysis was to investigate and quantify the relationship between obesity and dental caries in children.

Searches  of the Embase, MedLine, ScienceDirect, Ovid and PsychInfo databases were conducted,  restricted to studies published in English between 1980 and 2010. Relevant abstracts and articles were independently reviewed by three authors with two authors independently assessing quality.  A number of a priori subgroup analysis were planned and meta-analysis conducted.

• 14 studies were included, (1longitudinal 13 cross-sectional)
• Overall, a significant relationship between childhood obesity and dental caries (effect size = 0.104, 95% CI 0.001-0.206, P = 0.049) was found.
• However when analysed by dentition type there was a non-significant association
  • Permanent teeth  (effect size = 0.124, 95% CI: -0.053 to 0.301)
  • Primary teeth      (effect size = 0.093, 95% CI: -0.033 to 0.220)
• In studies using standardized measures for child obesity a significant association was noted between obesity and permanent teeth
  • BMI-for-age centiles (effect size = 0.189, 95% CI: 0.060–0.318, P = 0.004)
• Moderating for study country of origin (newly ‘industrialized’ versus industrialized) showed a significant relationship between obesity and dental caries in children from industrialized but not newly industrialized countries. Cofactors such as age and socioeconomic class were significant moderators.

The authors concluded

These results confirm a positive association between obesity and dental caries in the permanent dentition, although it is unclear what is the causative direction of this relationship?

Comment

The authors noted the previous systematic review on this topic Kantovitz et al 2006, that review had narrow inclusion criteria and one noted one study with high-level evidence showing no direct association.  In their discussion they also highlight potential issues with the quality of the included studies. Looking at the results this may mean that higher quality studies subsequently find that the suggested relationship is not substantiated. Equally people may not consider that this statistically significant result is not clinically important. Although, interestingly a larger effect size was noted in those studies with a more robust obesity measure.

Conflict of interest: – The Dental Elf is one of the authors of this paper

Links

Hayden C, Bowler JO, Chambers S, Freeman R, Humphris G, Richards D, Cecil JE. Obesity and dental caries in children: a systematic review and meta- analysis. Community Dent Oral Epidemiol 2012.

Kantovitz KR, Pascon FM, Rontani RM, Gavião MB. Obesity and dental caries—A systematic review. Oral Health Prev Dent. 2006;4(2):137-44. Review. PubMed PMID:16813143.