A nationwide survey in dental X-ray examination was performed in Japan and reported by UNS-CEAR, This time, we performed the nationwide survey using a questionnaire and estimated the frequency of radiographic examinations in Japan. The nominal tube voltage of the X-ray unit was usually, 60kV and a tube current of lOmA was most frequently used. Instant film with a speed group of C was most frequently used for intra-oral radiography. The frequency of using instant processing was similar to that of automatic processing in general hospital dental depart-ment and dental clinics, but automatic processing was used in all university hospitals. The fre-quency of X-ray examinations in dentistry in Japan was estimated 9287×104 for intra-oral expo-sures including 91.1×104 for bite-wing exposures and 3.9×104 for occlusal exposures in 1994, and 1104×104 for panoramic examination, The frequency of total of intra-oral and panoramic exami-nation was 10486×104 in 1994.
