The timing of tooth emergence is of considerable importance in the planning of prevention of occlusal caries. OBJECTIVE: The aim was to estimate the trends of emergence of the first permanent molars in girls and boys between 5-6 years of age, since more children are included in the first grade after Brazilian elementary education has been extended from eight to nine years of duration. METHODS: Dental spaces of 497 children aged 60 months or older were examined four times by a calibrated dentist (kappa > 0.97) during 18 months in a longitudinal study. The first permanent molar was considered emerged when any tooth surface could be reached by a ball point probe. Participants' age was measured in months; 95% confidence intervals were obtained for prevalence and incidence values for each sex in three age groups - 60.0 to 65.9; 66.0 to 71.9; 72.0 to 77.9 months. Incidence rate ratios were estimated by Poisson regression analysis. RESULTS: The majority of children from 66.0 to 71.9 months and 72.0 to 77.9 months presented at least one emerged permanent molar. For each three children in the 66.0-71.9-month group, at least one had all four permanent molars emerged. CONCLUSION: The emergence trends observed justify the need for specific protection and surveillance measures for occlusal caries prevention.
Epidemiology; Tooth eruption; Permanent dentition; Molar; Age; Gender
