Thirty-six impacted and displaced teeth in 29 patients were examined radiographically by using orthopantomography (OPG) and computed tomography (CT). CT scans were obtained by using both a conventional program and a dental CT software program. The radiographic images obtained were compared for visualization of the internal position, inclination of unerupted teeth, and diagnosis of contact and doubtful or clearly visible resorption of adjacent roots. Both CT methods were superior to OPG. As far as the internal position and inclination of the impacted teeth, direct contact, and clearly visible resorption are concerned, the conventional CT program yielded the same information as the dental CT program. However, the exact proportional cross-sectional views obtained by dental CT yielded significantly (P < 0.01) better information about doubtful root resorption in adjacent teeth than did conventional CT.