IAEA survey of dental cone beam computed tomography practice and related patient exposure in nine central and eastern european countries.
OBJECTIVES Cone beam computed tomography (CBCT) in dentistry and maxillofacial surgery is a widely used imaging method for the assessment of various maxillofacial and dental pathological conditions. The objective of this study was to summarize the results of a multinational retrospective-prospective study that focused on patient exposure in this modality. METHODS The study included 27 CBCT units and 325 adult and paediatric patients, in total. Data on patients, clinical indications, technical parameters of exposure, patient dose indicator, or, alternatively, dose to phantom were collected. The dose indicator used was air kerma-area product, PKA. RESULTS In most scanners operators are offered with a variety of options regarding technical parameters, especially the field-of-view (FOV) size. The median and the third quartile value of PKA for adult patients in 14 different facilities were 820 mGy cm² and 1000 mGy cm² (interquartile range, IQR = 1058 mGy cm²), and 653 mGy cm² and 740 mGy cm² (IQR = 1,179 mGy cm²) for children, as reported by four different institutions. Phantom dose data were reported from 15 institutions, and median PKA ranged from 125 mGy cm² to 1951 mGy cm². Median PKA values varied by more than a tenfold between institutions, mainly due to differences in imaging protocol used, in particular FOV and tube current-exposure time product. CONCLUSIONS The results emphasize the need for a cautious approach to using dental CBCT. Imaging only when the clinical indications are clear, accompanied with the appropriate radiographic techniques and the optimum imaging protocol, will help reduce radiation dose to patients.