RESUMEN
Congenital aplasia (agenesis) is an important development dental anomaly. There is a big discrepancy between the data on the prevalence of aplasia in dental literature. The authors analyzed orthopantomograms of 1875 children and adolescents at the Department of Dentistry for Children and Orthodontics of Semmelweis University. The prevalence of congenital aplasia was found 15.68% (294 subjects). There was no difference between the sexes. The most frequently missing teeth were the upper lateral incisors, the lower second premolars, the upper second premolars and the lower central incisors. The highest number of aplasia was detected in the second premolars (330 teeth). The frequency of aplasia of the molars was 0.74%. Oligodontia was found in 1.12%. The authors present two patients with aplasia and the successful treatment of the cases.