Establishment of diagnostic reference levels for quality control in panoramic radiography at public hospitals in Cyprus

Diagnostic reference levels (DRLs) help optimize panoramic radiography by balancing patient dose and image quality. Cyprus lacks national DRLs, highlighting the need to establish local DRLs (LDRLs) within State Health Services Organization (SHSO) hospitals as a part of quality assurance program. This study assessed imaging conditions for paediatric and adult patients undergoing panoramic radiography at SHSO hospitals to determine LDRLs. Patient data (age, sex), hospital location, exposure parameters, and dose area product (DAP) were extracted from the central PACS using the DOSE (Qaelum NV, Belgium) management system. Radiographs were acquired with four panoramic units at Nicosia General Hospital (NGH), Limassol General Hospital (LiGH), Larnaca General Hospital (LaGH), and Famagusta General Hospital (FGH). Third quartile DAP values were defined as LDRLs for paediatric (< 18 years) and adult (≥ 18 years) groups. DAP and exposure conditions were analysed based on hospital and sex groups. LDRLs were also compared with published reference values. The LDRLs were 116 mGycm2 for paediatric and 119 mGycm2 for adult patients. Mean DAP was significantly lower in paediatric patients (p < .001), although the decrease is relatively small (4%). Tube voltage was significantly higher in adults (p < .001). Significant inter-hospital differences in DAP and exposure parameters were observed (p < .001), with the highest doses recorded at LaGH due to elevated tube voltage and current. Adult males showed higher DAP than females (p < .05); in paediatric patients, significant sex-based differences were observed at NGH and in total dataset. SHSO DAP values were generally higher, except at LiGH and NGH that were comparable to or lower than those in the international literature. This study established LDRLs for panoramic radiography in Cyprus’ public hospitals, filling a critical gap in national radiation protection data and supporting legal compliance. The LDRLs may serve as baseline for optimizing dental radiographic practices within the SHSO. Higher DAP compared to international data suggest a need for enhanced dose optimization, particularly in paediatric imaging. Significant inter-hospital differences in DAP and exposure parameters, despite standardized equipment and protocols, highlighting the need for further standardization and quality improvement.