Objectives: The purpose of this population-based study was to quantify the incidence of radiographic procedures and the intervals between radiographic exposures.
Study design: The Florida Dental Care Study was a prospective cohort study of a representative sample of dentate adults. In-person interviews and dental examinations were conducted at baseline, with subsequent interviews every 6 months during 48 months of follow-up. Dental record information was abstracted afterward.
Results: Thirteen percent of all dental procedures, and 42% of all diagnostic procedures, were radiographic. Annual person-level incidence of receipt of any radiograph was 48%. Incidence of specific types of radiographic procedures ranged from 5% to 30%. Among the 45% of the sample population who had had more than 1 bitewing procedure, 70% of the intervals between bitewing exposures were 1 year or longer. Receiving more than 1 full-mouth series or panoramic radiographic in any 24-month period was very rare.
Conclusions: Annual incidence of radiographic procedures was substantially higher than the incidence reported in previous studies based on responses by dentists to hypothetical situations, but was stable during the 4 years of follow-up. On the basis only of intervals between exposures, and not of clinical status on the day of service, there was no substantial evidence of inappropriately frequent radiographic examinations.