Epidemiological Status of Third Molars in an Iranian Population

Impaction of third molars is a common phenomenon. The incidence of impacted third molars varies in different populations.
The aim of this study is to assess radiographic status (root development degree, angulation, and eruption level) of the third molar in Iranian population via panoramic radiographs.
Patients and 647 patients, ranging in age from 17 - 25, were selected from three regions of Iran. Based on their panoramic radiographs, their root development degree, angulation, and eruption levels were analyzed.
The angulation of upper third molars were vertical (44.6%), distoangular (44.1%), mesioangular (10.7%), and horizontal (0.6%). For lower third molars, the angulation was mesioangular (44.5%), vertical (33.8%), distoangular (12.2%), and horizontal (9.5%). The eruption levels of maxillary third molars were C > A> B, and for mandibular third molars they were A > B> C. The order of root development prevalence of the maxillary and mandibular third molars was complete > 2/3 > 1/3.
The most common status of impaction of the third molars in the maxilla was vertical angulation, level C of eruption, and complete root formation. In the mandible it was mesioangular, level A of eruption, and complete root formation. Since the study sample consists of patients from the north, middle, and south of Iran, the sample can represent the whole population of Iran.