A large sample-sized study on dental development of children treated at the Central Dental Clinic (OCEx) of the Brazilian Army

Objectives: To test and compare the performance of two radiographic methods for dental age estimation on a large sample of Brazilian boys and girls.Material and methods: The sample consisted of 1.990 panoramic radiographs of Brazilian children (age: 3–15.9 years) equally balanced based on sex. The sample was distributed into ten age categories, each with up to 200 children. Age estimation was performed with Willems’ (2001) and Demirjian’s (1973) methods. Estimated (EA) and chronological (CA) ages were compared. The performances of the methods were quantified based on sex and age category.Results: The overall differences between CA and EA for Willems’ method in boys and girls were 0.06 and − 0.02, respectively. For Demirjian’s method, the differences were 0.60 and 0.74, respectively. The overestimations of Demirjian’s method were statistically significant (p < 0.001). Willems’ method reached the best outcomes among children between 3 and 12 years, while Demirjian’s best performances were between the ages of 7 and 10 years.Conclusion: Willems’ method led to differences between CA and AE that were acceptable for clinical and forensic practice. Clinical relevance: Age estimation may guide clinical decisions based on treatment timing. Validating international tools is necessary to promote evidence-based practice and country-specific application. This study overcame the limitations of previous research to provide a more realistic perspective of the performance of age estimation methods in Brazilian children. Willems’ method had a superior performance compared to Demirjian’s method and led to outcomes that were better than most studies with the Brazilian population.