Abstract
Background: Impaction of third molars is a common phenomenon. The incidence of impacted third molars varies in different
populations.
Objectives: 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 Methods: 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.
Results: 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.
Conclusions: 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.