June 2006

Various publications have reported the prevalence of accessory teeth to be between 1 and 3%. In contrast, hypodontia has a much higher prevalence. In the current work, the authors studied OP radiographs on 2,219 patients aged 6 to 18 years who presented at the Department of Paedodontics and Orthodontics at Semmelweis University in Budapest (patients with systemic disease were excluded). The examined radiographs revealed a prevalence of accessory teeth of 1.53%. The sequence of prevalence was as follows: mesiodens > second incisor > first incisor. 77.5% of the accessory teeth were located in the upper jaw, with 97.5% of those being present in the incisor region. Hypodontia was detected in 326 patients (14.69%); missing wisdom germs were not considered. The sequence of prevalence of missing germ was as follows: upper second incisor > lower second premolar > upper second premolar > lower first incisor. Hypodontia in the molar region was observed in 15 cases (0.68%). The prevalence of oligodontia was 1.04%. Key words: Accessory tooth, hyperdontia, hypodontia, oligodontia, paedodontic and orthodontic patients, partial anodontia, supernumerary tooth, supplementary tooth, total anodontia