The effect of developer age on the diagnostic accuracy of endodontic file's length

Radiography wide usage in root canal treatments and developer age important role on attaining definite diagnosis, the present study examined the developer age effects on the diagnostic accuracy of endodontic file's length using D-speed, E-speed and E/F-speed films. In this diagnostic study, radiographies were processed by developer weekly up to 6 weeks. The films were viewed by 5 postgraduate Endodontics and Radiology students who assessed file tip position, using a 3-point confidence scale. The area under the curve (Az) were calculated and used as a diagnostic accuracy scale. Film types and endodontic file size effects were analyzed by one-way analysis of variance (ANOVA), Tukey post hoc and student t tests. E-speed and D-speed film diagnostic accuracy were similar being higher than E/F speed films (p<0.0001). D, E, and E/F films. Az values in fresh, 2 week and 4 week developer were 0.5882, 0.5538, 0.3578 and 0.5782, 0.5718, 0.3498 and 0.6196, 0.6724, 0.2080 respectively. Developer age did not decrease the D and E film diagnostic accuracy but reducing E/F films on 4 weeks. The 6 weeks developer caused the radiographies not to be readable. All observers showed higher diagnostic accuracy viewing endodontic file size of 15 than 10 (p<0.0001). The mean Az values in endodontic file size of 10 and 15 using fresh, 2 weeks and 4 weeks developer age were 0.3984, and 0.6016, 0.3732, and 0.6268, 0.2774 and 0.7226. The developer age up to 4 weeks did not significantly affect the diagnostic accuracy of D-speed and E-speed films. E/F films cannot be used in developer older than 2 weeks; however, its usage was associated with lower accuracies compared to E and D-speed films.