Patient Entrance Dose for Intraoral Dental Radiography in Trang, Phatthalung and Satun Provinces

Abstract

          High radiation dose can induce radiation hazard to patient, so the radiology technician should consider for the minimum dose to get the best result of radiography. In 2017, the Regional Medical Sciences Center 12/1 Trang (RMSC 12/1 Trang) studied radiation dose used for dental radiography in Trang, Phatthalung and Satun provinces and compared to the Diagnostic Reference Levels (DRLs) of the Department of Medical Sciences (DMSc). The doses were measured at open-end cone, called Patient Entrance Dose (PED). The exposure techniques were set for 6 dental areas, those included maxillary incisor, mandible incisor, maxillary canine-premolar, mandible canine-premolar, maxillary molar and mandible molar teeth. The data were collected from 59 intra-oral X-ray units, while 48 units were film system (81.4%) and 11 units were digital image system (18.6%). It was found that the doses obtained from the 6 dental areas were 2.5, 2.1, 3.5, 2.5, 4.3 and 3.1 mGy, respectively. These results were higher than those of the Diagnostic Reference Levels (DRLs) issued by DMSc which were 2.3, 1.9, 3.1, 2.4, 4.0 and 3.1 mGy, respectively. Hence, the RMSC 12/1 Trang informed the relevant hospitals and clinics to adjust the proper exposure techniques to reduce radiation doses. The study was carried out again in 2019 and the data were recorded from 77 intra-oral X-ray units: 62 units were film system (80.5%) and 15 units were digital image system (19.5%). The doses obtained from the 6 dental areas were 2.0, 1.7, 2.7, 2.2, 3.6 and 2.6 mGy, respectively. Obviously, these data were lower than the doses obtained in 2017 and the DRLs issued by DMSc. In conclusion, the PED could be reduced by using the corrected exposure techniques and the digital image system might also use less dose.