GafChromic XR‐QA film in testing panoramic dental radiography

The location and field size of the incident X-ray beam in panoramic dental radiography cannot be ascertained visually most of the time. However, these parameters are needed for quality control and dosimetry determination. To alleviate this problem, we tested GafChromic XR-QA film on two panoramic systems. For each system, we used the length of a cross-sectional image of the incident beam and the exposure measurement with a pencil ion chamber to compute the dose-area product. The result was confirmed by direct analysis of a dose distribution on a film. Placement of the ion chamber was determined by the latter images. The GafChromic XR-QA version of radiochromic film has thus been demonstrated to usefully complement a pencil ion chamber in the testing of a panoramic radiography system.