Evaluation of the Distortion Rate of Panoramic and Periapical Radiographs in Erupted Third Molar Inclination

Background/objective: panoramic and periapical radiographs are normally used in impactedthird molar teeth surgeries. the aim of the present study was to evaluate and compare thedistortion of the erupted third molar teeth on panoramic and periapical radiographs.patients and methods: a total of 44 radiographs were obtained of 22 patients (age range,18-24 years) referred to the faculty of dentistry for orthodontic treatment. a plaster cast wasprepared and panoramic radiography was taken for all patients to plan the orthodontic treatmentand periapical radiography was taken for investigation of tooth structure details. therefore, atotal of 66 views and samples were studied by two methods: 1) measuring the angle betweenthe longitudinal plane of the third molar and occlusal plane. 2) measuring the angle betweenthe longitudinal plane of second and third molar. finally, 132 records were evaluated by oneindividual.results: there was no significant statistical difference between the mean position of the thirdmolar on panoramic, periapical radiographs and the casts. however, measurements of the thirdmolars on periapical radiographs were slightly closer to the measurements of the casts comparedto the panoramic radiographs.conclusion: distortion does not have a specific effect on the diagnosis of the position of thethird erupted molars by periapical or panoramic radiographs, though various studies have shownthat these radiographs have an amount of distortion and periapical radiographical distortion is lessthan that in panoramic radiography.