Association between breastfeeding duration and mandibular retrusion: A cross-sectional study of children in the mixed dentition

Introduction: In this study, we examined the relationships among breastfeeding duration, nonnutritive infantile sucking habits, Class II facial patterns with mandibular retrusion, and Class II dental relationships. Methods: A sample of 249 children in the mixed dentition was examined by 2 orthodontists. Data about the duration of breastfeeding and nonnutritive sucking habits were obtained by written questionnaires answered by the parents. Results: The chi-square test did not indicate a statistically significant association between breastfeeding duration and mandibular deficiency or Class II malocclusion. However, statistically significant associations were found between short breastfeeding duration (<6 months) and nonnutritive sucking habits, and between nonnutritive sucking habits and Class II malocclusions. Conclusions: These findings point to the hypothesis that nonnutritive sucking habits may work as a dominant variable in the relationship between breastfeeding duration and the occurrence of Class II malocclusion. However, the prevention of mandibular deficiency should not be listed as one of the advantages of breastfeeding.