[Chronology of permanent tooth eruption in Argentinian children]

The knowledge of the ages at which individual teeth emerge in a given ethnic group is essential for the planning of preventive measures and the treatment on malocclusion within a population. A number of factor such as sex, ethnic characteristics, etc, have been found to be related to emergence timing of the permanent teeth; however ages assessed in other countries cannot be used because of considerable variation from one country to another. This investigation was performed on a cross-sectional sample of 4735 randomly-selected caucasian and amerindian children from 10 geographic regions of Argentina, including the Federal District. Mean ages of eruption were computed using probit procedure. Mean times of emergence of the permanent (except third molars) showed practically no difference between the two ethnic groups. In both samples all teeth emerged earlier in girls. Since it seems that the mean time of emergence of the permanent teeth occurs at least one year before the commencement of schooling, preventive measures should be applied before that age.