Paediatric organ and effective doses in dental cone beam computed tomography

摘要

Cone beam computed tomography (CBCT) is an x-ray emerging technology with wide applications in the dental and maxillofacial disciplines. Dental CBCT has been associated with higher radiation risk to the patients compared to conventional dental x-ray imaging.Several studies have investigated the radiation doses involved in dental CBCT for adults but none has looked into paediatric doses. This study estimates the organ and effective doses to two paediatric tissue-equivalent phantoms using thermoluminescent dosimeters for three dental CBCT units and six imaging protocols. The doses to the thyroid, salivary glands and brain ranged from 0.068mSv to 1.131 mSv, 0.708mSv to 2.009mSv and 0.03 lmSv to 1.584mSv respectively. The skin and red bone marrow have received much lower doses than the other three organs.The effective doses ranged from 0.022 mSv to 0.081 mSv. The highest effective dose was calculated for the NewTom VG using the dental protocol and the lowest was observed for the Next Generation i-CAT using the 6cm maxilla protocol. The effective doses calculated in this study were much higher than these of panoramic x-ray imaging but lower than conventional CT.