Purpose: The purpose of this study was to evaluate the prevalence of sleep bruxism and associated factors in three- to five-year-olds.
Methods: A representative cross-sectional study was conducted with a sample of 749 preschool children during immunization campaigns. Data acquisition involved an oral clinical exam, anthropometric measures, and a questionnaire administered in interview form. All data were analyzed using the chi-square test and Poisson regression with robust variance with the aid of SPSS software.
Results: The prevalence of sleep bruxism among preschool children was approximately 14 percent. Statistically significant associations were found: between sleep bruxism and lower dental crowding (prevalence ratio=3.38; 95% confidence interval=1.9-5.7); for the habit of biting on objects (PR=2.49; 95% CI=1.4-4.4); for duration of breast-feeding for a period longer than 12 months (PR=1.98; 95% CI=1.2-3.2); and for bottle-feeding for more than 24 months (PR=1.93; 95% CI=1.2-3.1).
Conclusions: Lower arch crowding, the habit of biting on objects, and prolonged breast-feeding and bottle-feeding were associated with sleep bruxism in the preschool children analyzed in the present study.