There were some limitations to our study. First, our study did not investigate socioeconomic status, as the municipality did not allow us to collect such data. Several studies have reported the impact of socioeconomic status on ECC. Preschool children, especially those living in poor socioeconomic situations, are susceptible to dental caries, perhaps owing to their relatively poor nutrition, low emphasis on health behaviors, and insufficient access to dental care. In addition, Azevedo et al reported that a prolonged period of breastfeeding can be associated with a low educational level and socioeconomic status.