Equivalent dose, effective dose and risk assessment from panoramic radiography to the critical organs of head and neck region

The purpose of this study was to evaluate the equivalent and effective dose, and estimate radiation risk to the critical organs of head and neck region from the use of adult and child mode in panoramic radiography. The results were as follows. 1. The salivary glands showed the highest equivalent and effective dose in adult and child mode. The equivalent and effective dose in adult mode were 837 μSv and 20.93 μSv, those in child mode were 462 μSv and 11.54 μSv, respectively. 2. Total effective doses to the critical head and neck organs were estimated 34.2l μSv in adult mode, 20.14 μSv in child mode. From these data, the probabilities of stochastic effect from adult and child mode were 2.50xl0-6 and 1.47x10-6 3. The other remainder showed the greatest risk of fatal cancer. The risk estimate were 4.5 and 2.7 fatal malignancies in adult and child mode from million examinations. The bone marrow and thyroid gland showed about 0.1 fatal cancer in adult. and child mode from these examinations.