A RADIOGRAPHIC METHOD FOR MEASURING RADIATION-DOSE BASED ON BEAM QUALITY

Objectives: To develop a radiographic method for measuring radiation d ose based on beam quality for inexpensive postal surveys of general de ntal practitioners. Methods: Different beam qualities were simulated t o expose a commercially available film (X-Omat MA 18 x 22.4 cm, Ready Pack, Kodak Pathe, Paris, France). Density and contrast curves were fi tted by means of 4th-degree polynomial functions. The curves were used to estimate beam quality (as the first HVL) and radiation dose in air for 22 different dental X-ray machines by means of linear interpolati on. These estimations were compared with the measurements obtained wit h the NERO system and an ionization chamber (paired t-test). Results: No significant differences were found between the radiographic and the conventional methods in determining beam quality and radiation dose. Conclusions: The radiographic method can be used to determine beam qua lity and radiation dose of dental X-ray machines from a single exposur e. The radiographic method is simple and inexpensive and causes a mini mum of disruption to the dental practice.