TESTING THE CONSISTENCY OF MEASUREMENTS OF THE DISTANCE BETWEEN THE CEMENTO-ENAMEL JUNCTION AND THE ALVEOLAR BONE CREST ON BITEWING RADIOGRAPHS

The purpose of the research described in this paper is to test the con sistency of measurements of the distance between the cemento-enamel ju nction and the alveolar bone crest (CJ-AC) on bitewing radiographs. Th e present paper shows how the consistency tests were organized and whi ch statistical analyses were used. Since the actual characteristic (CJ -AC) could not alter, the variations of the results had to be due to o ne more of the 5 m- factors (man, material, machine, method and manipu lation). To test the consistency of the measurements of CJ-AC, a prete st and an en route test were performed. Both the bitewing radiographs for the pretest and the en route test were sampled at random from the principal material. The principal material consisted of 856 sets of bi tewing radiographs from persons born 1930-1949. The pretest of 40 sets of bitewing radiographs were read twice by 2 independent readers. The en route test consisted of 85 sets of bitewing radiographs which were read twice by 1 reader. Neither the results of the pretest nor the re sults of the en route test showed statistical or clinical differences of significance. In conclusion the consistency of this method of measu ring is satisfactory for the 2 readers.