الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 97 |  |  |
| | | from | 97 | | |
Abstract
Aim of study : This study was performed to compare the shaping ability of One Curve, Hyflex EDM and ProTaper Next systems in simulated S-shaped canals. Materials and methods : Sixty clear resin blocks with simulated S-shaped canals were divided into three groups; group 1: simulated canals were prepared using One Curve instruments, group 2: simulated canals were prepared using Hyflex EDM instruments, and group 3: simulated canals were prepared using ProTaper Next instruments. Photos of the simulated canals were taken before and after instrumentation by a digital camera fixed on a photographic jig used for standardization of the images. The simulated canals were prepared to an apical size of # 25 according to the manufacturer’s instruction for each file system. Composite images were obtained by superimposition of pre- and post-preparation images. The amount of removed resin was measured at 11 levels by using an image analysis software and a prepared measurement scale. Canal transportation and curvature straightening were determined. Instrument fracture and canal aberrations were also recorded. The data were statistically analyzed by using the Kruskal-Wallis, post hoc Dunn and chi-square tests. Results : One Curve removed less amount of resin than Hyflex EDM and ProTaper Next. One Curve caused significantly less canal transportation and straightening than Hyflex EDM and ProTaper Next at apical curve and at both curves respectively. At levels (0, 6 and 7), Hyflex EDM produced less transportation than ProTaper Next. At the straight portion of the canal, there was not significant difference between the tested groups regarding canal transportation. No significant difference was noted betweenHyflex EDM and ProTaper Next regarding canal straightening. No instrument was fractured. There was no significant difference among the tested files in the incidence of canal aberrations. Conclusion : Under the conditions of this study, the newly developed One Curve system produced more conservative and centered preparations of S-shaped canals than the Hyflex EDM and ProTaper Next systems did.