Collective doses and risks from dental radiology in Great Britain.

The continued expansion of dental radiology in Britain up to the end of 1981 is demonstrated, with a rate of increase much in excess of that seen for general medical radiography. Of the total of 7.8 X 10(6) dental X-ray examinations undertaken in 1981 approximately 6.7 X 10(6) were intra-oral, 1.5 X 10(5) were extra-oral and 9.1 X 10(5) were pantomographic. Weighted dose equivalents for typical examinations in each of these categories were calculated using specific weighting factors for the important "remainder" organs. Values of 20 muSv, 30 muSv and 80 muSv were obtained for intra-oral, extra-oral and pantomographic techniques, respectively, corresponding to risks of fatal malignancy of 0.33, 0.5 and 1.3 per million. The estimated collective weighted dose equivalent of 212 man Sv to the population of Britain from the current level of dental radiology is predicted to result in no more than about three extra cases of fatal cancer when the age- and sex-related opportunity for manifestation of radiation-induced cancers is taken into account.