口内法ディジタルX線画像のアルミニウム当量画像

抄録

The purpose of this study was to evaluate intraoral digital images converted to aluminum-equivalent images and their characteristics. Using DixelR, pixel value distributions were mea-sured for various exposure doses and the average pixel values calculated. Image of radiograph with aluminum wedge was transferred to a personal computer and converted to an aluminum-equivalent image. The original digital and aluminum-equivalent images were evaluated by four observers for the detection of hole on the aluminum block phantoms. As a result, there was no effect of the exposure time on the pixel values for dark current. The dose - response curves of the Dixel systems indicated that the pixel values increased in proportion to the radiation expo-sure. The original digital image changed according to exposure dose, however aluminum-equiva-lent images showed constant quality in the range of exposure time from 0.07 to 0.17sec. Furthermore, there was no effect of the exposure time on the aluminum-equivalent values of enamel, dentin, alveolar bone and pulp cavity. Aluminum-equivalent images were superior to the original digital images by visual evaluation using ROC analysis.