Quality Assurance and Quality Control

Quality assurance (QA) in dental and maxillofacial radiography requires that specific steps are taken to provide diagnostic images while minimizing patient radiation exposure.^1,3 This is accomplished through compliance with manufacturer and regulatory measures regarding device usage.^1,3 Quality Control (QC), an integral part of QA, concentrates on testing and measurement of radiographic devices, image receptors, and other technical components of the imaging chain.^3,13 The purpose of QC is to ensure that the entire imaging system maintains a consistent level of acceptable performance according to national standards and guidance.^1,3,14,15

To ensure consistent high-quality panoramic images, a quality assurance program should be in place and conducted by qualified personnel. NCRP Report 177 advises that the QA/QC program be established in consultation with a qualified expert to include procedures for documentation of QC measures, designation of qualified personnel responsible for each activity, monitoring of results, and mechanisms to enact corrective actions to remedy identified issues or substandard performance.¹ It is recommended that a retake log be maintained to help monitor the number of retakes and the causal errors. Identification of recurring errors indicates a need for continuing education and in-service staff training to eliminate repeated errors and unnecessary patient re-exposure.

Specifically x-ray machines should be inspected periodically for output, kilovoltage calibration, half value layer, timer accuracy, milliamperage reproducibility, and collimation as required by state law. Regular testing, planned monitoring, and scheduled maintenance of x-ray equipment, digital image receptors, scanning and display equipment are all important aspects of a comprehensive QA/QC program.¹ In addition, machine operators must be qualified and credentialed according to state regulations.