Περίληψη: | To begin with, Dental Cone Beam Computed Tomography lies in theacquaintance of multiple images of the patient with the rotation of a scannerin 180-220 degrees. After a reconstruction procedure, digital volumesare formed with the final images depicted. Specifically the objective ofthe current study focuses on the measurement and assessment of specificimage quality parameters, qualitative and quantitative, in order specificdirective guidelines to be given to the dentist regarding the performance ofthe machine. In other words the following study not only aims to follow atypical image quality procedure but to explain the impact the experimentalpart has on the clinical part.Subsequently in the experimental part were involved a CBCT machinethe Planmeca ProMax 3-D Classics and the Mini CT QC Phantom. Infurther analysis two scans were performed (Tube Voltage:90 kVp and 84kVp) while other parameters remained constant (Tube Current:14 mAs,slice thickness: 0,2 mm and exposure time: approximately 12 s). Furtheranalysis was made by measuring and estimating specific parameters in twoROIs (small and large) as well as examining their behavior regarding the slice selection, the ROI size and tube voltage.It was concluded that the image quality parameters (mean, std, median,SNR, contrast, CNR) were affected by those selections in most times.Specifically the slice selection in the center of the material gave moreaccurate results, the ROI size affected the std and SNR inside the materialand at last the tube voltage also affected in different ways all the above parameters.
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