Endo Training Blocks Research Articles

Root Canal Anatomy Preservation of WaveOne Reciprocating Files with or without Glide Path

Introduction This study evaluated the influence of glide path on canal curvature and axis modification after instrumentation with WaveOne Primary reciprocating files. Methods Thirty ISO 15, 0.02 taper Endo Training Blocks were used. In group 1, glide path was created with PathFile 1, 2, and 3 at working length, whereas in group 2, glide path was not performed. In both groups, canals were shaped with WaveOne Primary reciprocating files at working length. Preinstrumentation and postinstrumentation digital images were superimposed and processed with Matlab r2010b software to analyze the curvature radius ratio (CRr) and the relative axis error (rAe), representing canal curvature modification. Data were analyzed with 1-way balanced analyses of variance at 2 levels ( P < .05). Results Glide path was found to be extremely significant for both CRr parameter (F = 9.59; df = 1; P = .004) and rAe parameter (F = 13.55; df = 1; P = .001). Conclusions Canal modifications seem to be significantly reduced when previous glide path is performed by using the new WaveOne nickel-titanium single-file system.

Investigation on the Shaping Ability of Nickel-Titanium Files When Used with a Reciprocating Motion

Introduction The introduction of nickel-titanium (NiTi) files into clinical practice has improved the quality of canal shaping, but increasing the curvature of the root canal (or the diameter of the master instrument that prepares the full working length) could result in more transportation, straightening, and aberration of the canal. Nickel-titanium instruments are significantly safer and have an extended cyclic fatigue life when used with a reciprocating movement. The purpose of this study was to compare the shaping ability of FlexMaster NiTi instruments when used in either continuous or reciprocating movements. Methods Thirty-two Endo Training Blocks ISO 15, 2% taper, 10-mm radius of curvature, and 70° angle of curvature were prepared, according to the group, with FlexMaster NiTi instruments either in continuous rotation or in reciprocating (60° clockwise, 40° counterclockwise) movement. Preoperative and postoperative images of the simulated canals were taken under standardized conditions. The preoperative and postoperative images were combined exactly. The amount of resin removed was determined both for the inner (convex) and the outer (concave) sides of the curvature at 10 different points. Results In the most apical third of the canal, the Continuous group produced the largest enlargement of the canal as compared with the Reciprocating group ( P < .05). In the apical third, the Continuous group displayed significantly greater enlargement of the canal at the external side. Conclusions The shaping of simulated canals is more centered by using a reciprocating motion when compared with continuous rotation, but the reciprocating motion could be more time-consuming.

Use of Nickel-Titanium Rotary PathFile to Create the Glide Path: Comparison With Manual Preflaring in Simulated Root Canals

The study compared changes to canal curvature and incidence of canal aberrations after preflaring with hand K-files or with nickel-titanium rotary PathFile in S-shape Endo Training Blocks. The influence of the operator's expertise was also investigated. One hundred training blocks were colored with ink, and preinstrumentation images were acquired digitally. Preflaring was performed by an endodontist with PathFile (group 1) and hand stainless steel K-files #10-15-20 (group 2); an inexpert clinician performed preflaring with PathFile (group 3) and hand stainless steel K-files (group 4). Preinstrumentation and postinstrumentation images were superimposed to evaluate the outcomes investigated. Differences in canal curvature modification and incidence of canal aberration were analyzed with the Kruskall-Wallis plus post hoc tests and by the Monte Carlo method, respectively, ( P < .05). The PathFile groups demonstrated significantly less modification of curvature ( P < .001) and fewer canal aberrations ( P < .001). No expertise-related difference was found within instrument groups ( P > .05), whereas the inexpert clinician produced more conservative shaping with Pathfiles than did the expert with manual preflaring ( P < .01).

Hand-operated and Rotary ProTaper Instruments: A Comparison of Working Time and Number of Rotations in Simulated Root Canals

The aim of this study was to compare the effective shaping time and number of rotations required by an endodontist working with hand and rotary ProTaper instruments to completely shape simulated root canals. Eighty Endo Training Blocks (curved canal shape) were used. Manual preflaring was performed with K-Flexofiles #08-10-12-15-17 and #20 Nitiflex at a working length of 18 mm. Specimens were then randomly assigned to 2 different groups (n = 40); group 1 was shaped by using hand ProTaper and group 2 with ProTaper rotary. The number of rotations made in the canal and the effective time required to achieve complete canal shaping were recorded for each instrument. Differences between groups were analyzed with the nonparametric Mann-Whitney U test ( P < .05). Hand ProTaper required significantly fewer rotations ( P < .001) than rotary ProTaper, whereas the effective working time to fully shape the simulated canal was significantly higher ( P < .001) with hand ProTaper.