Developmental stages of the third molar in Israeli children.

PURPOSE The purpose of this study was to examine the developmental stages of the third molar in Israeli children, compare its development in boys and girls, in the maxilla and mandible, right to left sides in various age groups, and relate the developmental stage to chronological age. METHODS Panoramic radiographs of 693 healthy children and adolescents (328 boys and 365 girls) ages 7 to 16 were analyzed using a modified 6-stage method. Since the 16-year-old group was too small for statistical analysis, it was later excluded from the study. Radiographs were obtained from patient files. RESULTS There were no significant differences in the development of the third molar between boys and girls and between right and left sides. Slight differences were found between the maxilla and mandible. The first appearance of a radiolucent bud was at age 8.7 in the mandible and 9.3 in the maxilla. Crown completion was observed on average at age 11.7 in the maxilla and 11.8 in the mandible. CONCLUSIONS There was a high correlation between third molar development and chronological age. Agenesis can be determined conclusively if no radiolucent bud is present beyond age 14. The modified 6-stage method allowed more accurate determination of developmental stages.