Association of breastfeeding and malocclusion in 5-year-old children: Multilevel approach.

Background: Breastfeeding plays an important role in child health, including the development of normal dental occlusion, but large epidemiological findings on the association breastfeeding-malocclusion are lacking.
Aim: To investigate the association between the proportion of breastfed children in the city level and the prevalence of malocclusion in the primary dentition at age 5.
Design: This cross-sectional analysis used data from national population surveys on oral health and on breastfeeding practices. Data refer to 5278 5-year-old children and 44 Brazilian towns. Information on malocclusion and individual sociodemographic characteristics were obtained from the 2010 Brazilian Oral Health Survey. Breastfeeding rates during the first year of life were extracted from the Breastfeeding Prevalence Survey in Brazilian Towns. Population sociodemographic data were analysed as confounder. Multilevel Poisson analyses were performed.
Results: Malocclusion prevalence was 63.3%. Towns exhibiting higher prevalence of breastfeeding among 9- to 12-month-olds presented lower prevalence of malocclusion among children at age 5 (PR 0.98; 95% CI 0.98-0.99).
Conclusions: Lower prevalence of malocclusion among 5-year-old children was associated with a higher proportion of children breastfed at ages 9 to 12 months at a city level, regardless of sociodemographic factors. These findings highlight the importance of encouraging breastfeeding during a child's first year.
(© 2018 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)