Assessment of Absorbed Radiation Dose of Some Soft and Hard Oral Tissues after Panoramic and Cone Beam CT Radiograph

Purpose: The goal of the this study is to measure absorbed dose of oral tissues such as oral mucosa, salivary gland and bone after exposure to ionizing radiation through panoramic radiograph and cone beam CT. Subjects and Methods: about 50 Egyptian patients were selected in this study who were referred to the department of oral medicine, periodontology, oral diagnosis & radiology, Faculties of Dental Medicine, Al-Azhar university for panoramic or cone beam examination for various dental purposes. Patients were divided into two groups (25 patients each). First Group was subjected to panoramic examination and the second one was subjected to cone beam examination. The systems used were a Planmeca Viso CBCT and Orthopantomogram OP-100 panorama. Assessment of the patient radiation dose was done by thermoluminescent dosimeter (TLD) on the patients. The absorbed radiation dose is then recorded. Data was then analyzed, and statistical calculations were performed. Results: The absorbed radiation skin doses ranged between (130 µGy, 2817.8 µGy) in panorama and (327.99 µGy, 11994 µGy) in CBCT for one exposure. When digital panoramic unit and CBCT were compared, panoramic imaging is 25-37% of CBCT. Parotid gland and oral mucosa absorbed the greatest radiation dose for all panoramic and CBCT patients. CBCT radiation doses are considerably higher than those of digital panoramic unit. Conclusion: The prospective benefits of CBCT in maxillofacial disciplinary are undoubted; but, it is important that their use be totally justified above conventional technique before they are done.