Students' attitudes to digital radiography and measurement accuracy of two digital systems in connection with root canal treatment.

The aim of this study was to evaluate students' attitudes towards digital radiography and measurement accuracy in digital images recorded with a CCD-sensor and a photostimulable phosphor (PSP) plate radiography system in connection with root canal treatment. Thirty-one dental students participated in an endodontic course. Two single-rooted teeth were assigned at random to two receptors for digital radiographic examination, either (i) the RVG-ui CCD sensor or (ii) the Digora PSP plate system. After the endodontic treatment had been completed for the first tooth, the student filled in a questionnaire on their use of the digital system. Thereafter, the students switched radiography system and repeated the procedure for the second tooth. Eventually, the students completed the questionnaire by answering questions that directly compared the two digital systems. The gutta-percha filled tooth was measured using the system's own software. Two measurements of each tooth were performed: total tooth length (TTL) and root filling length (RFL). The teeth were dismounted from the plaster blocks and the true TTL and RFL was measured with an electronic slide calliper. The majority of the students had used the contrast enhancement facility (CCD sensor = 52%, PSP = 71%) and the zoom facility (65-68%) whilst some had used the density enhancement facility (CCD sensor = 39%, PSP = 55%). The students stated that they saved more time when they used the CCD sensor than when they used the PSP system (P < 0.001), and that it was easier to position the tooth with the PSP plate than with the sensor (P < 0.01). The lengths measured on the digital images from both digital systems were marginally larger than the true tooth lengths (P < 0.05). However, there was no difference between the two digital systems for the TTL/RFL ratio (P > 0.05).