Objectives: The purpose of this study was to evaluate the clinical and radiographical characteristics of non-syndromic hypodontia and hyperdontia in the permanent dentition.Study design: This study included 139 patients. Clinical and radiographical examinations were carried out by two examiners. Number and localization of missing or supernumerary teeth, and pathologies associated with the teeth, were recorded. Other teeth in the mouth were also examined for the presence of additional dental anomalies.Results: A total of 256 congenitally missing teeth were observed in 102 patients, and 73 supernumerary teeth were observed in 37 patients. The rate of missing teeth was much higher in females (67.6 %) than males (32.4 %) and in the maxilla (64.5 %) than mandible (35.5 %). The rate of supernumerary teeth was slightly higher in males (59.5 %) than females (40.5 %) and in maxilla (53.4 %) than mandible (46.6 %). The most common hypodontia type was mild to moderate hypodontia (62.7 %) and the most observed hyperdontia was a single supernumerary tooth (54.1 %). Microdontia, talon cusp, taurodontic molars were observed in 18.6 % of patients with hypodontia; and microdontia and dilacerated molars were observed in 8.1 % of patients with hyperdontia.Conclusions: Although missing and supernumerary teeth are asymptomatic in most cases, they may lead to malocclusions, aesthetic, functional and psychological problems.