Maternal breastfeeding, parafunctional oral habits and malocclusion in adolescents: a multivariate analysis

Malocclusion may result in esthetic impairment and functional disorders such as bad chewing, speech and swallowing, with a negative impact on quality of life. There is uncertainty regarding the effects of breastfeeding on dentofacial malocclusions. The purpose of the study was to evaluate the relationship between maternal breastfeeding and dental malocclusions and facial characteristics in adolescents with permanent dentition.

Probabilistic sampling of 2060 12- to 15-year-old students in a cross-sectional study was used. Malocclusion, as defined by Angle, and facial characteristics were the dependent variables. The duration of breastfeeding was the main independent variable. Other covariates were tested as effect modifiers or confounders. The associations were estimated using the odds ratio (OR) in multinomial logistic regression analysis (α=5%).

There was an association between a short duration of breastfeeding (less than 6 months) and Angle class II (OR=3.14; 95% CI: 1.28-7.66) and class III (OR=2.78; 95% CI: 1.21-6.36) malocclusion only in students with a prolonged history of bruxism. A higher occurrence of severe convex profile (OR=3.4; 95% CI: 0.63-18.26) and a lower occurrence of cancave profile (OR=0.43; 95% CI: 0.21-0.88) were also observed only among adolescents who had been breastfed for a short period and exposed to a long periods of mouth breathing.

These findings support the hypothesis that breastfeeding alone seems not to be directly associated with malocclusions, but it may have a synergetic effect with parafunctional oral habits on the development of occlusofacial problems. It is recommended that deleterious oral habits be avoided, especially by children who were breast-fed for less than 6 months.