Objective: To evaluate the frequency and characteristics of non-syndromic hypodontia and hyperdontia in the permanent dentition.
Material and Methods: Clinical files and panoramic radiographs of 6200 subjects, aged between 6-18 years, were evaluated. Subjects with supernumerary teeth and congenitally missing teeth were reevaluated. Age, gender, number and type of supernumerary or missing teeth, the location and pattern of distribution in the maxillary and mandibular arches as well as associated dental anomalies and pathologies were recorded.
Results: The prevalence of hypodontia and hyperdontia was 7.26% and 2.97%, respectively. In 184 subjects (56.5% males and 43.5% females) 233 supernumerary teeth and in 450 subjects (58.7% females and 41.3% males) 1111 congenitally missing teeth were recorded. The percentage of supernumerary teeth was higher in the maxilla (88.4%) than in the mandible (11.6%). The most frequent supernumerary teeth were the mesiodens (48.5%) followed by incisors (25.3%), premolars (15.5%) and distal molars (10.7%). The percentage of congenitally missing teeth was higher in the maxilla (58.1%) than in the mandible (41.9%). The maxillary lateral incisor (28.1%) and mandibular second premolar (26.4%) were the most frequently absent teeth. The prevalence of associated dental anomalies was 10.1% for hypodontia and 23.2% for hyperdontia.
Conclusions: Hypodontia and hyperdontia subjects should be evaluated carefully by periodic clinical and radiographic examinations to minimize possible future complications caused by associated dental anomalies.