DOSE REDUCTION IN DENTAL RADIOGRAPHY

All exposures to ionizing radiation for medical and dental purposes carry risks to both the patient and staff. It is now accepted practice that all exposures should be kept as low as reasonably practicable to minimize these risks. The various methods currently available for dose limitation in intraoral and panoramic radiography and their effects on image quality are considered. In intraoral radiography the use of fast (E-speed) film and rectangular collimation offer dose reductions of approximately 50 per cent and 60 per cent respectively. Constant potential X-ray units, longer focus-to-skin distances and rare-earth filtration will permit further dose reductions. In panoramic radiography the radiation dose to the patients can be reduced by up to one-eighth by combining the use of constant potential X-ray units, rare-earth intensifying screens and rare-earth filtration. © 1990.