Effect of breastfeeding on malocclusions: a systematic review and meta-analysis

AIM: The objective of this systematic review was to investigate whether breastfeeding decreases the risk of malocclusions.

METHODS: Six databases were systematically searched to the end of October 2014. Observational and interventional studies were included. Breastfeeding was evaluated in three categories: (i) ever versus never; (ii) exclusive versus absence of exclusive; and (iii) longer periods versus shorter periods. All types of malocclusion were considered as the outcome. Pooled adjusted odds ratio and its 95% confidence interval (95%CI) were obtained from meta-analyses. Heterogeneity was assessed with both the Q-test and the I-square. Funnel plots and Egger's test were employed to assess publication bias.

RESULTS: Forty-eight studies were included in the systematic review, and 41 were included in the overall meta-analysis (n = 27 023 participants). Subjects who were ever breastfed were less likely to develop malocclusions than those never breastfed (OR 0.34; 95% CI 0.24; 0.48), those who were exclusively breastfed presented lower risk to present malocclusion than those with absence of exclusive breastfeeding (OR 0.54; 95% CI 0.38; 0.77), and subjects longer breastfed were less likely to have malocclusions than those shorter breastfed (OR 0.40; 95% CI 0.29; 0.54).

CONCLUSION: Breastfeeding decreases the risk of malocclusions.