Chronology of First Permanent Molar Eruption among Children from the municipalities of Santa Helena and Três Barras do Paraná, PR, Brazil

Abstract

Objective: To determine the chronology of first permanent molar eruption in children of both sexes in order to compare the findings with the standard age described in the literature. Material and Methods: This was a cross-sectional study carried out in the municipalities of Santa Helena and Três Barras do Paraná, Paraná state, Brazil. The data were collected through a a specific form. The teeth were considered to be erupted when any portion of the crown was clinically visible. Results: The mean age for eruption of the first permanent molar was 72 to 83 months. The female group showed a mean age for eruption earlier (73 and 74 months) than that of the male group (74 and 75 months). However, a total of 154 (25%) permanent first molars erupted in children below this age (48 to 60 months). In general, the first permanent molar first erupted in the mandible, which corresponded to 36% in females and 34% in males. Element #36 (first lower left molar) was the most presente tooth in 21% of females and 20% of males. Conclusion: The mean age for eruption of the first permanent molar corresponded to that described in the literature at 72 months (6 years), although a considerable number of children aged 48-60 months were found to have this tooth erupted. Furtermore, this tooth first erupted in the mandible, particularly element#36, and females showed earlier eruption than males. DESCRIPTORS Molar.Tooth Eruption.Dentition.Permanent.Child.Epidemiology.