Single-file Systems Research Articles

Evaluation of Root Dentinal Damage Associated with ProTaper Gold, WaveOne Gold, and ProTaper Next during Cleaning and Shaping Procedures: An In vitro Analysis.

Aim:The purpose of this study is to evaluate and compare the incidence of dentinal defects after root canal shaping using rotary nickel-titanium (Ni-Ti) instruments (ProTaper Gold [PTG] and ProTaper Next [PTN]) and reciprocating instrument (WaveOne Gold [WOG]).Materials and Methods:One hundred human mandibular premolars with single root and single canal with canal curvature <10° were randomly divided into five groups (n = 20 teeth per group). The root canals were instrumented using hand K-files (positive control), full sequence rotary files PTG and PTN, and reciprocating single-file system WOG. One group was left unprepared and served as negative control. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a stereomicroscope.Results:PTG, WOG, and PTN showed dentinal defects in 40%, 53.3%and 30% of the samples, respectively.Conclusion:Irrespective of motion kinematics, dentinal defects are observed in all the Ni-Ti file groups. Within the limitations of the present study and the available literature, incidence of dentinal defects is less with instruments working in continuous rotation rather than instruments with reciprocating motion.

QUANTITATIVE EVALUATION OF APICALLY EXTRUDED DEBRIS DURING BIOMECHANICAL PREPARATION OF ROOT CANAL USING THREE SINGLE FILE SYSTEMS - AN IN-VITRO STUDY

Introduction: Root canal therapy comprises 3 main steps- access preparation, biomechanical preparation, and 3D obturation. During this process, debris is pushed out from the canals causing inter-appointment flare-ups and postoperative pain. Materials And Method: 60 extracted mandibular premolars with straight single canal were selected; the Eppendorf tubes were pre-weighted before instrumentation and were allocated into 3 groups along with the sample teeth.All the samples were instrumented with 3 single file systems i.e. Oneshape, Reciproc, and WaveOne Gold, and debris was collectedintheEppendorftubes.Thedebriscollectedwasweighedinananalyticalbalancetodeterminetheextrudeddebris. Results: The results of this study showed that WaveOne Gold resulted in the least amount of periapical debris extrusion while Reciproc extruded the maximum amount of debris as compared with other file systems. Conclusions: A thorough comparison of various systems in the extrusion of debris may be beneficial so that the best method with the lowest incidence of extrusion may be selected.

Apical extrusion of debris produced by the heat treated single-file systems XP-Endo Shaper, Reciproc Blue and ProDesign Logic

Aim: This study evaluated the apical extrusion of debris during root canal preparation produced by the single-file systems XP-Endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland), Reciproc Blue (VDW GmbH, Munich, Germany), and ProDesign Logic (Easy Equipamentos Odontologicos, Belo Horizonte, MG, Brazil). Methodology: Thirty single straight root canals in mandibular premolar were prepared and randomly assigned to 3 groups (n=10), according to instrument used for root canal preparation: XP-Endo Shaper, Reciproc Blue, or ProDesign Logic. Root canal shaping technique was performed by root segments and the apically extruded debris were collected and quantified using a debris collection setup with Eppendorf tubes and agar gel. Mean values were obtained by subtracting the initial weight of the test apparatus without specimens from its weight after root canal preparation. Then, one-way analysis of variance (ANOVA) followed by Bonferroni post hoc test were applied for comparison of values. The statistical significance level was set at 5%. Results: No significant difference was observed among groups (P>0.05), but all the instruments produced debris extrusion from the apical foramen. Conclusion: The heat treated single-file systems XP-Endo Shaper, Reciproc Blue, and ProDesign Logic produce similar amounts of apically extruded debris during root canal preparation. All single-file systems evaluated promoted apical extrusion of debris.

Apical extrusion of bacteria following the use of reciprocating single-file and rotary multi-file instrumentation systems in oval root canals

Objective: All instrumentation techniques and instruments are associated with apical extrusion during chemomechanical preparation, and this causes postoperative pain and flare-up. However, it is controversial whether reciprocal systems or rotary systems cause more apical extrusion. The objective of this in vitro study was to determine the differences in the amounts of apically extruded bacteria (AEB) associated with nickel-titanium rotary and reciprocating systems when used in oval-shaped root canals. Material and Methods: Seventy human mandibular premolar teeth with oval-shaped canals were randomly assigned to four experimental groups (15 teeth in each group) and one control group (10 teeth). The root canals were contaminated with Enterococcus faecalis and instrumented using two full-sequence rotary instruments (ProTaper Universal [PTU] and ProTaper Next [PTN]) and two reciprocating single-file instruments (Reciproc [R] and WaveOne [WO]). A 0.9% NaCl solution was used as an irrigant, and the bacterial extrusion was quantified as the number of colony-forming units for each sample. The results were statistically analyzed using the Kruskal-Wallis one-way analysis of variance and the Mann-Whitney U test, and the statistical significance level was set at p &lt;0.05. Results: The R system was associated with the highest amount of bacterial extrusion (p &lt;0.05). The PTU system caused more bacterial extrusion than the PTN and WO systems (p &lt;0.05). There was no significant difference between the PTN and WO systems (p &gt;0.05). Conclusions: All instrumentation techniques caused apical bacterial extrusion. The instrument design and preparation techniques affect the number of extruded bacteria.KEYWORDS Apical extrusion; Bacteria; Endodontics; Root canal preparation.

Comparison of OneShape, 2Shape and One Curve endodontic instruments for debris and irrigant extrusion.

Better understanding is needed about the debris-and-irrigant-extrusion potential of the instruments used for root canal preparation procedures, manufactured of different heat-treated alloys. The aim of the study was to evaluate the single-file nickel-titanium (NiTi) rotary system OneShape® and compare it with 2 different heat-treated instrumentation systems produced by the same manufacturer - a single-file C-wire system (One Curve®) and a multi-file T-wire system (2Shape®) - in terms of debris and irrigant extrusion. The mesiobuccal root canals of 51 extracted mandibular molar teeth were selected for the study. The roots were applied to the test apparatus prepared with the Myers and Montgomery method. The roots were divided into 3 groups according to the instrumentation system: OneShape; One Curve; and 2Shape. The root canals were prepared according to the manufacturer's instructions. The analysis of variance (ANOVA) and the post hoc Tukey tests were used to evaluate the significance of the amount of the extruded debris and irrigant (p < 0.05). The One Curve group produced less debris extrusion than the 2Shape group (p < 0.05). There were no significant differences between the 2Shape and OneShape (p = 0.136), or the One Curve and OneShape groups (p = 0.159). The weight of the extruded irrigant was significantly lower for the One Curve group as compared to other systems (p < 0.05). The mean weight of the extruded irrigant did not differ significantly for the 2Shape and OneShape groups (p = 0.976). The C-wire One Curve system was associated with less apical irrigant extrusion in comparison with the OneShape and 2Shape systems. The amount of debris extrusion produced by the One Curve system was similar to that produced by the OneShape system and lower than in the case of the 2Shape system.

Comparative Evaluation of Dentinal Microcrack Formation by Single Reciprocating File Systems: An In Vitro Study

Comparative Evaluation of Dentinal Microcrack Formation by Single Reciprocating File Systems: An In Vitro Study

Apical extrusion of debris with different rotary and reciprocating single-file endodontic instrumentation systems: a systematic review and meta-analysis protocol.

IntroductionRoot canal treatment is one of the oldest dental procedures for the treatment of endodontic infection. Extrusion of debris beyond the root apex during root canal instrumentation and subsequent persistence of pain are common complications. A systematic review of the evidence on reciprocating single-file instrumentation systems and their comparison with rotary single-file systems, with apical extrusion of debris as primary outcome, will be done through this study.Methods and analysisPublished ex vivo and in vitro studies with no language restriction will be included. We will search MEDLINE (Ovid), EMBASE (Ovid), Web of Science, Cochrane and Google Scholar. Strategies will be incorporated to search grey literature also. Thorough evaluation of search results, completion of data abstraction and assessment of quality will be done by two reviewers independent from each other. Assessment of included studies will be done by utilising an evidence model developed on the basis of standards of quality reported in guidelines to document ex vivo and in vitro studies regarding dental materials and pertained for extrusion of debris apically and has been already used in quality assessment of studies involving quantification of debris extrusion apically. We will calculate the standardised mean differences for apically extruded debris, with congruent 95% CIs. We will measure the statistical heterogeneity by applying the Cochrane Q test and quantify using the I2 statistic. Existence of covariates and any potential heterogeneity will be explored through prespecified subgroup and sensitivity analyses.Ethics and disseminationApproval from an ethical research committee is not required because it will be done using data that have been already published and have no concerns related to the privacy of patients. Extensive dissemination of results from this review will be done through submission to a peer-reviewed journal for publication and conferences.PROSPERO registration numberCRD42019151804.

Disinfection and outcome of root canal treatment using single-file or multifile systems and Ca(OH)2 medication.

This clinical study reports on the antibacterial effects and outcome of endodontic treatment using either a single-file or a multifile system, associated with calcium hydroxide interappointment medication. The root canals of single-rooted teeth with apical periodontitis were treated by using either Reciproc or BioRaCe instrument systems, 2.5% NaOCl irrigation, and calcium hydroxide medication. Bacteriological samples taken before preparation and immediately before obturation were evaluated for total bacterial counts by quantitative real-time polymerase chain reaction (qPCR). Patients were followed up and the treatment outcome was assessed by clinical and radiographic criteria. Decreasing lesions were classified as success in a lenient criterion or failure in a rigid one. Bacteria were detected in all initial samples (47 cases) and were significantly reduced after treatment in both groups (p<0.001). In the Reciproc and BioRaCe groups, 7/25 (28%) and 11/22 (50%) root canals yielded negative qPCR results before obturation, respectively (p>0.05). Quantitative bacterial reduction was similar between groups (p>0.05). The success rate in the BioRaCe group was 95.5% and 77% in the loose and rigid criterion, respectively. In the Reciproc group, corresponding figures were 88% and 76%. Differences in outcome were not significant (p>0.05). No diseased case showed negative qPCR results for bacteria. A difference of >1 Log10 counts was observed between healed and diseased cases. Root canal treatments of teeth with apical periodontitis using a single-file or a multifile system for preparation, associated with NaOCl irrigation and calcium hydroxide interappointment medication, showed similar antibacterial effectiveness and success rate.

BetheSF: Efficient computation of the exact tagged-particle propagator in single-file systems via the Bethe eigenspectrum

Single-file diffusion is a paradigm for strongly correlated classical stochastic many-body dynamics and has widespread applications in soft condensed matter and biophysics. However, exact results for single-file systems are sparse and limited to the simplest scenarios. We present an algorithm for computing the non-Markovian time-dependent conditional probability density function of a tagged-particle in a single-file of N particles diffusing in a confining external potential. The algorithm implements an eigenexpansion of the full interacting many-body problem obtained by means of the coordinate Bethe ansatz. While formally exact, the Bethe eigenspectrum involves the generation and evaluation of permutations, which becomes unfeasible for single-files with an increasing number of particles N. Here we exploit the underlying exchange symmetries between the particles to the left and to the right of the tagged-particle and show that it is possible to reduce the complexity of the algorithm from the worst case scenario O(N!) down to O(N). A C++ code to calculate the non-Markovian probability density function using this algorithm is provided. Solutions for simple model potentials are readily implemented including single-file diffusion in a flat and a ‘tilted’ box, as well as in a parabolic potential. Notably, the program allows for implementations of solutions in arbitrary external potentials under the condition that the user can supply solutions to the respective single-particle eigenspectra. Program summaryProgram Title: BetheSFCPC Library link to program files:http://dx.doi.org/10.17632/3bs74vf72n.1Licensing provisions: MITProgramming language: C++ (C++17 support required)Supplementary material: makefile, README, SingleFileBluePrint.hppNature of problem: Diffusive single-files are mathematical models of effectively one-dimensional strongly correlated many-body systems. While the dynamics of the full system is Markovian, the diffusion of a tracer-particle in a single-file is an example of non-Markovian and anomalous diffusion. The many-body Fokker–Planck equation governing the system’s dynamics can be solved using the coordinate Bethe ansatz. A naïve implementation of such a solution runs in non-polynomial time since it requires the generation of permutations of the elements of a multiset.Solution method: In this paper we show how, exploiting the exchange symmetries of the system, it is possible to reduce the complexity of the algorithm to evaluate the solution, using a permutation-generation algorithm, from O(N!) in the worst case scenario to O(N) in the best case scenario, which corresponds to tagging the first or the last particle, where N stands for the number of particles in the single-file.Additional comments including restrictions and unusual features: The code may overflow for large single-files N≥170. All the benchmarks ran on the following CPU: Intel Xeon E3-1270 v2 3.50 GHz 4 cores. The compiler used is g++ 7.3.1 (SUSE Linux) with the optimization-O3 turned on. The code to produce all the data in the figures is included in the files: figure2.cpp, figure3.cpp, figure4.cpp, figure5a.cpp and figure5b.cpp

COMPARATIVE EVALUATION OF RADICULAR DENTINE THICKNESS IN DANGER ZONE OF MANDIBULAR FIRST MOLAR AFTER INSTRUMENTATION WITH TWO DIFFERENT ROTARY SYSTEMS USING CBCT - AN INVITRO STUDY

Introduction: The mandibular first molar poses a series of anatomic challenges such as multiple canals, isthmuses, lateral canals, and apical ramifications. Additionally, the distal surface of mesial root presents a thin zone, which is 4-6 mm cervical to canal orifice with a thin area of dentin termed as “danger zone,” as it increases the risk of perforation of furcal dentin during mechanical instrumentation.&#x0D; Aim: To measure the amount of the dentin removed after biomechanical preparation with XP-Endoshaper and Neoendo flex files in the danger zone of the mandibular first molar using CBCT.&#x0D; Methodology: Twenty-four mandibular first molars, the mesial roots of which presented a curvature of 20-30 degrees, were selected using the Schneider method. Samples were instrumented with Neoendo rotary file system (n=12) and XP-Endoshaper rotary single file system (n=12). The samples were scanned using CBCT before and after instrumentation. The analyzed parameter includes the remaining dentin thickness at the danger zone of the mandibular 1st molar. The obtained data were subjected to statistical analysis.&#x0D; Results: There was no significant difference in remaining dentine thickness between the two rotary systems (p &gt; 0.05).&#x0D; Conclusion: XP-Endoshaper revealed better results than Neoendo rotary files. However, both rotary file systems showed no significant difference in the remaining dentin thickness in the danger zone of the mandibular first molar.&#x0D; Keywords: Danger zone, Remaining dentine thickness, XP EndoShaper, NeoEndo, CBCT.

Debris extrusion during root canal preparation with nickel-titanium instruments using liquid and gel formulations of sodium hypochlorite invitro.

This study compared the amount of apically extruded debris during root canal preparation with three single-file systems using liquid and gel-based formulations of sodium hypochlorite (NaOCl) or distilled water. Seventy-two single-canalled roots were divided into three groups: HyFlex EDM (Coltene-Whaledent); Reciproc Blue (VDW); and F-One Blue (Shanghai Fanta) and then divided into three subgroups: NaOCl liquid (Imicrly), NaOCl gel (Cerkamed Medical) and distilled water. The amount of extruded debris was calculated by determining the dry weight of the debris collected. Data were analysed using Kruskal-Wallis test with Bonferroni correction. Debris extrusion occurred in all subgroups. Both the instrument and the irrigant had an impact. The F-One Blue tended to extrude the least debris, though no significant difference was observed in the pairwise comparisons between instruments. NaOCl liquid resulted in significantly more extruded debris than NaOCl gel or distilled water. The results lead us to conclude that the NaOCl gel reduced debris extrusion compared to NaOCl liquid.

Effect of 2 Heat-treated Nickel-Titanium Files on Enlargement and Deformation of the Apical Foramen in Curved Canals: A Scanning Electronic Microscopic Study

IntroductionThe aim of this study was to evaluate under scanning electronic microscopy the enlargement and deformation of the apical foramen of curved mesiobuccal roots with both reciprocating and rotary single-file systems made of a newly heat-treated alloy through the use of Reciproc Blue (REC Blue; VDW, Munich, Germany) and XP-endo Shaper (XPS; FKG Dentaire, La Chaux-de-Fonds, Switzerland). MethodsForty mesiobuccal roots of mandibular and maxillary molars presenting a curvature ranging from 20°–40° were used in this study. The apical foramens were initially scanned with a scanning electronic microscope under 200× magnification. Roots were divided into 2 groups (n = 20): the REC Blue group instrumented with the REC Blue system and the XPS group instrumented with the XPS system. Both groups were instrumented at the foramen. The apical foramens were scanned after root canal preparation. The area, circularity, and ratio of the Feret diameters were calculated from each image. The Kolmogorov-Smirnov, Mann-Whitney, and Wilcoxon tests were used for statistical analysis (P ≤ .05). ResultsThe area of the foramen increased significantly after canal shaping with REC Blue and XPS. The variation of the area was significantly greater with XPS. However, there were no significant differences in circularity and the ratio of the Feret diameters with both instruments. ConclusionsNo transportation was found when using REC Blue and XPS. The newly heat-treated nickel-titanium alloy did not promote deformation of the apical foramen in curved canals.

Quantitative Assessment of the Efficacy of Two Different Single-file Systems in Reducing the Bacterial load in Oval-Shaped Canals: A Clinical Study

IntroductionThis randomized clinical study compared the in vivo antibacterial efficacy of Reciproc Blue (RB), XP-endo Shaper (XP-S), and XP-endo Shaper associated with XP-endo Finisher (XP-F) systems in infected oval-shaped root canals with primary apical periodontitis. MethodsIn this study, 28 human teeth with a single root and a single canal were randomly assigned to 2 groups according to the instrumentation technique: group 1, RB (n = 14) and group 2, XP-endo (XP-S and XP-F, n = 14). The single-rooted teeth were prepared by reciprocating and rotary nickel-titanium instruments with 5.25% sodium hypochlorite irrigation. Samples were collected from the canal at the baseline (S1), after chemomechanical preparation (S2), and after XP-F instrumentation (S3). The DNA extracts were subjected to quantitative analysis for total bacterial counts by quantitative real-time polymerase chain reaction. The data were analyzed using the analysis of variance test, and the level of significance was set at 5%. ResultsAll samples tested positive for the presence of bacteria at baseline, and the bacterial counts substantially reduced after treatment procedures (P < .01). The results showed no statistical difference between RB and XP-S instrumentation with respect to the bacterial reduction (P > .05). A marked bacterial reduction was observed after the use of the XP-F instrument (P < .01). ConclusionsThe XP-S and RB systems sharply reduced the bacterial load in oval-shaped root canals with primary apical periodontitis. XP-F used as a supplementary instrument to chemomechanical preparation promoted a significantly higher bacterial reduction.

Comparative evaluation of cyclic fatigue fracture resistance of newer Ni Ti rotary files: An in vitro study

The single-file technique has been developed for shaping the vast majority of canals, regardless of their length, diameter, or curvature. Aim: This study compared the cyclic fatigue fracture resistance in canal after instrumentation with single file system and multiple file system i.e- One Curve, F360 (single file systems) and Neoendo (multiple rotary file).Method: Ten rotary instruments of each type and totalling 30 instruments of 25 mm in length were divided into 3 groups. Group 1: Neoendo, Group 2:F360, Group 3: One Curve. The dental hand piece was mounted on a mobile device that allowed for the simple placement of each instrument inside the artificial canal. To prevent the instruments from slipping out and to allow for observation of the instruments, the artificial canals were covered with glass. The time was then converted into number of cycles to failure. NCF = Number of rotations per minute x Time to fracture.Result: The mean values of time in seconds to fracture in F360 were lowest followed by Neoendo and highest was found in One Curve group.

Generalized hydrodynamic analysis of transport through a finite open nanopore for two-component single-file systems

Single-file diffusion (SFD) in finite open nanopores is characterized by nonzero spatially varying tracer diffusion coefficients within a generalized hydrodynamic description. This contrasts with infinite SFD systems where tracer diffusivity vanishes. In standard tracer counterpermeation (TCP) analysis, two reservoirs, each containing a different species, are connected to opposite ends of a finite pore. We implement an extended TCP analysis to allow the two reservoirs to contain slightly different mixtures of the two species. Then, determination of diffusion fluxes through the pore allows extraction of diffusion coefficients for near-constant partial concentrations of the two species. This analysis is applied for a lattice-gas model describing two-component SFD through a finite linear pore represented by a one-dimensional array of cells. Two types of particles, A and B, can hop only to adjacent empty cells with generally different rates, h_{A} and h_{B}. Particles are noninteracting other than exclusion of multiple cell occupancy. Results reveal generalized hydrodynamic tracer diffusion coefficients which adopt small values inversely proportional to pore length in the pore center, but which are strongly enhanced near pore openings.

Shaping ability of XP-endo Shaper and ProTaper Next in long oval-shaped canals: a micro-computed tomography study.

To evaluate the shaping ability of the single-file XP-endo Shaper system (XP-S; FKG Dentaire, La Chaux-de-Fonds, Switzerland) employing a different working time and of the multiple-file ProTaper Next system (Dentsply Sirona, Ballaigues, Switzerland) using micro-computed tomography (micro-CT) technology. Twenty long oval-shaped canals in mandibular incisors were matched anatomically and scanned by micro-CT (Skyscan 1172; Bruker micro-CT, Kontich, Belgium). The canals were divided into two groups (n=10) according to the canal preparation protocol: XP-endo Shaper (XP-S) with an extra 45s of instrumentation and ProTaper Next (PTN X4). The images recorded before and after preparation were evaluated for morphometric measures of volume, surface area, structure model index and untouched walls. The data were compared statistically (Student's t-test for homogenous variances and Mann-Whitney test) between the two groups (XP-S and PTN X4) at α=5%. Root canal preparation significantly increased all parameters (volume, surface area, structure model index and untouched walls) tested in each group (P<0.05). There was no significant difference (P>0.05) in the percentage increase of volume (107.50%-93.13%), surface area (27.74%-29.68%) or untouched canal wall (13.08%-11.74%) between XP-S and PTN X4, respectively. The XP-endo Shaper system (single-file) with an extra 45s of instrumentation and the ProTaper Next system (multiple files) had a similar root canal shaping ability. Neither technique was able to fully prepare the long oval-shaped canals of mandibular incisors.

Effect of XP-endo Finisher on Post-Instrumentation Pain after Using Different NiTi Rotary Systems

Purpose: This study was conducted to assess and compare the effect of XP-endo Finisher on post-instrumentation pain after using either One Shape single-file rotary system or ProTaper Universal multi-file rotary system in root canal preparation. Materials and Methods: Forty-eight consented patients, with 52 single-rooted teeth requiring endodontic treatment were selected for this study based on inclusion/exclusion criteria. Teeth were randomly assigned into two equal groups according to the NiTi rotary system used for root canal preparation, Group (I), One Shape rotary system was used and Group (II), ProTaper Universal rotary system was used. Each group was further subdivided into two equal subgroups (A and B) according to whether XPendo Finisher was used in finishing the root canal preparation or not. Pain Intensity was measured using modified visual analogue scale at 6, 12, 24 and 72 hours after root canal instrumentation. Results: The patients’ highest mean pain scores occurred in the first 24 hours and significantly declined at the subsequent observation time of 72 hours. ProTaper Universal groups showed the highest mean pain scores, while the lowest mean pain scores were found in One Shape groups with no significant difference. The highest mean pain scores were found in XP-endo Finisher subgroups, while the lowest were found in No XP-endo Finisher subgroups with no significant difference. Conclusion: One Shape system produced less postoperative pain when used in conjunction with XP-endo Finisher.

Clinical and Radiographic Evaluation of WaveOne Gold Single-File System in Pulpectomy of Primary Molars: A Randomized Clinical Trial

Clinical and Radiographic Evaluation of WaveOne Gold Single-File System in Pulpectomy of Primary Molars: A Randomized Clinical Trial

Comparison of Shaping Ability of Different Single-File Systems Using Microcomputed Tomography.

Objectives To evaluate the shaping ability of four different single-file systems using micro-computed tomography (micro-CT). Materials and Methods Eighty mesiobuccal and mesiolingual canals of permanent mandibular molars were randomly assigned to four groups according to the file used; WaveOne Gold, RECIPROC Blue, HyFlex EDM, and One Shape ( n = 20). The samples were scanned using micro-CT for the preinstrumentation record; then the canals were instrumented and scanned for the postinstrumentation records. Statistical Analysis The data were then analyzed statistically using one-way analysis of variance (ANOVA) with the level of significance set at α = 0.05. Results The results of canal centering ratio and canal transportation showed that no significant difference was found among the four file groups at the middle and the coronal levels. However, a significant difference was found at the apical level ( p < 0.05), where WaveOne Gold showed the best centering ratio and the least amount of canal transportation. The change in the canal volume was significant at the coronal level ( p < 0.05), whereas the change in the canal volume was higher for the HyFlex EDM group than the other groups. No significant difference was found between the other groups at the apical level, middle level, or in the total percentage of canal volume. Conclusion WaveOne Gold produced a more centralized canal preparation with a lesser amount of transportation at the apical level. HyFlex EDM showed the highest canal volumetric change at the coronal level. The interim design of the endodontic files has a high impact on the behavior of the file inside the root canal.

A Stereomicroscopic Analysis of Dentinal Micro Cracks after Root Canal Preparation Using Four Different Rotary Instruments.

A variety of single-engine driven files and kinematics have been introduced to improve the clinical performance of NiTi rotary files. The purpose of this in vitro study was to measure and compare the incidence of dentinal defects after root canal preparation with different single file systemsA variety of single-engine driven files and kinematics have been introduced to improve the clinical performance of NiTi rotary files. The purpose of this in vitro study was to measure and compare the incidence of dentinal defects after root canal preparation with different single file systems