Affiliation: School of Dentistry, Department of Orthodontics
To address the important issues surrounding the CBCT imaging modality we have initiated an investigation of CBCT dosimetry and its relation to image quality in pediatric and adult patients. RANDO, ATOM adult and ATOM child phantoms were scanned with the i-CAT Next Generation CBCT machine at the 17x23cm field of view. Each phantom houses 24 optical stimulated luminescent (OSL) dosimeters or thurmolumonescent (TLD) dosimeters. Dosimeter readings were used to calculate equivalent dose, effective dose and patient risk using 2007 ICRP guidelines. OSL calibration and correction was verified using an ion chamber, NanoDot OSL dosimeters and a medical radiography system. Effective dose calculations ranged between 71μSv (TLD) and 65μSv (OSL) for the RANDO phantom and 70 and 71 for the Adult and child phantoms respectively. Our results validate optical stimulated luminescent dosimeters and the ATOM phantoms as efficient and accurate tools to estimate the effective dose of CBCT scans.