RESUMO
OBJECTIVE: To evaluate the relationship between breastfeeding duration and the prevalence of non-nutritive sucking habits in children with deciduous dentition. METHOD: A cross-sectional survey was conducted on the mothers of 551 children aged 3 to 6 years, randomly selected from public pre-schools in São Paulo, Brazil. Mothers were asked to complete a questionnaire that included items regarding their children's age, gender, race, method and duration of infant feeding, as well as pacifier use and/or digit-sucking habits. According to the answers pertinent to the method and duration of infant feeding, children were assigned to five groups: 1--never breastfed, 2--breastfed for a period shorter than 3 months of life, 3--breastfed for 3 to 6 months, 4--breastfed for 6 to 9 months, and 5--breastfed for 9 months or longer. Data were submitted to the Fisher's exact test with Bonferroni correction for multiple comparisons to analyse possible associations between breastfeeding duration period categories and non-nutritive sucking behaviours. RESULTS: Pacifier use frequency was high in groups 1, 2, 3 and 4 (85%, 87.6%, 78% and 70%, respectively), in comparison with that in group 5 (38.6%). The prevalence of non-nutritive sucking habits was significantly reduced in children who were breastfed for nine months or longer (p = 0.000). There were no statistically significant differences in the frequencies of pacifier use and/or digit-sucking habits between genders, regardless of the breastfeeding duration period. CONCLUSION: Children aged 3-6 years who were breastfed for nine months or longer had a lower prevalence of non-nutritive sucking habits.