Infant breast-feeding and childhood caries: a nine-year study

This study's purpose was to assess the association between infant breast-feeding and caries experience of primary second molars in a nine-year longitudinal cohort study.

Study sample was 509 subjects recruited at birth. Information about breast-feeding duration and other factors was collected through parents' responses to periodic questionnaires. Primary teeth were examined for dental caries at five years old and nine years old by calibrated dentist examiners. Caries experience (yes/no) and number of decayed and/or filled surfaces (dfs) were determined for five- and nine-year-olds.

For primary second molars at five years old, 18 percent of children who were breast-fed less than six months had caries (mean dfs=0.55) while only 9 percent of children who were breast-fed at least six months had caries (mean dfs=0.33). From five to nine years old, caries incidence was 32 percent and 31 percent, respectively, for children breast-fed less than six months and at least six months. In multivariable regression analyses, shorter breast-feeding duration was positively associated with caries experience of primary second molars at five years old (P=.005), both before and after controlling for other important factors.

Shorter duration of breast-feeding is suggested to be associated with increased risk for early childhood caries, but its impact might diminish with age.