Simulated S-shaped Canals Research Articles

Comparison of shaping ability of the Reciproc Blue and One Curve with or without glide path in simulated S-shaped root canals.

This study aimed to assess the impact of a glide-path on the shaping ability of 2 single-file instruments and to compare the centering ability, maintenance of original canal curvatures and area of instrumentation in simulated S-shaped root canals. Forty simulated S-shaped root canals were used and were prepared with One Curve (group OC), One G and OC (group GOC), Reciproc Blue (group RB) and R-Pilot and RB (group PRB) and scanned before and after instrumentation. The images were analyzed using AutoCAD. After superimposing the samples, 4 levels (D1, D2, D3, and D4) and 2 angles (Δ1 and Δ2) were established to evaluate the centering ability and modification of the canal curvatures. Then, the area of instrumentation (ΔA) was measured. The data were analyzed using 2-way analysis of variance and Tukey's test for multiple comparisons (p < 0.05). Regarding the centering ability in the apical part (D3, D4), the use of the glide-path yielded better results than the single-file groups. Among the groups at D4, OC showed the worst results (p < 0.05). The OC system removed less material (ΔA) than the RB system, and for Δ1, OC yielded a worse result than RB (p < 0.05). The glide-path improved the centering ability in the apical part of the simulated S-shaped canals. The RB system showed a better centering ability in the apical part and major respect of the canal curvatures compared with OC system.

Shaping ability of different single-file rotary systems in simulated S-shaped canals by a new investigation approach: An in vitro study

Introduction: The aim of this study was to compare the shaping ability of single-file nickel–titanium systems in simulated S-shaped canals. Materials and Methods: Sixty simulated S-shaped canals were photographed and 12 levels along their length were determined. They were divided into four groups: A and B where the WaveOne Gold and Reciproc Blue reciprocating systems were used and Groups C and D for the OneCurve and Fanta-AF F-one rotary systems. Blocks were re-photographed and the before- and after-preparation photos were superimposed. Canals' widths were measured at each canal's level before and after preparation to calculate canals' deviations. The preparation times were recorded, and the data were analyzed by one-way ANOVA and Chi-square tests (P = 0.050). Results: The mean deviation in the middle third (0.14 mm) was greater than those in the coronal (0.08 mm) and apical thirds (0.09 mm) (P = 0.000). Furthermore, in this third, the OneCurve system caused the lowest greatest deviation (0.13 mm) but not different from the WaveOne Gold system (0.18 mm). At the apical third, the OneCurve showed the least mean deviation (0.07 mm) (P = 0.001) and the lowest mean of the greatest deviation (0.12 mm) (P = 0.000). Significantly, the highest percentage of the greatest deviations located within the canals' middle third (68.4%). The Fanta-AF-F-one and Reciproc Blue systems had higher percentages of the greatest deviation within the middle third (86.7% and 85.7%, respectively) than the OneCurve (42.9%) and WaveOne Gold systems (57.1%) (P = 0.013). The OneCurve and WaveOne Gold systems needed the least shaping times (57.15 and 63.07 s, respectively). Conclusions: The OneCurve system followed by the WaveOne Gold system had better shaping ability than other systems. The OneCurve and WaveOne Gold systems required shorter shaping times. The “greatest-deviation” can be more appropriate analysis than the mean deviation when the shaping ability is investigated.

Shaping ability of ProTaper Next and Navigator EVO rotary nickel–titanium file systems in simulated L-shaped and S-shaped root canals

Objective: The objective of this study is to evaluate and compare the shaping ability of ProTaper Next (PTN) and Navigator EVO (N-Evo) rotary file systems in L- and S-shaped simulated resin root canals. Materials and Methods: A total of forty L-shaped (n = 20) and S-shaped (n = 20) resin block root canals were randomly assigned into four groups (n = 10) based on the PTN and N-Evo rotary file systems. Before the instrumentation, simulated root canals were filled with the India blue ink and preinstrumentation images were taken using a digital camera. Each canal was prepared to the standard working length 16 mm, 0.15 mm apical foramen diameter, and 0.2 initial tapers. After the canal preparation, red India ink was filled in each canal and postoperative images were obtained. The two images were superimposed, five points were selected, and canal widths were measured with image analysis software. Canal preparation time, file failure, and presence of aberrations were recorded and compared between the two systems. Descriptive statistics of mean and standard deviation and inferential statistics of Independent samples t-test and analysis of variance tests were applied to the data. Results: PTN file system showed significantly lesser preparation time (L-shape, 2.55 ± 0.38 min, and S-shape, 2.57 ± 0.44 min) in comparison to N-Evo file system (L-shape, 5.01 ± 0.37 min, and S-shape, 5.21 ± 0.30 min) (P Conclusions: N-Evo file system demonstrated better shaping ability compared to PTN in L- and S-shaped simulated canals. PTN file system prepared the canal in less time and maintained the original curvature. An almost similar number of canal aberrations found between tested file systems. However, three N-Evo files broke in L-shaped canals indicating possible limitation in this area.

Impact of new cross-sectional designs on the shaping ability of rotary NiTi instruments in S-shaped canals.

The aim was to compare the shaping ability of different rotary nickel-titanium instruments in simulated S-shaped canals. One hundred S-shaped canals in resin blocks were prepared to an apical size 25 using F6 SkyTaper (Komet), Silk Files .04, Silk Files .06, Prototypes .04, and Prototypes .06 (all Mani) (20 canals/group). Material removal was measured at 20 measuring points, beginning 1mm from the endpoint of preparation. Incidence of canal aberrations, preparation time, and instrument failures were also recorded. Statistical analyses were performed using ANOVA, Student-Newman-Keuls and Chi-square test. Pooled data of all measuring points revealed that canals instrumented with Prototypes .04 were significantly better centered than those prepared with all other instruments, while Prototypes .06 and both Silk Files performed significantly better than F6 SkyTaper (p < 0.05). The preparation time differed significantly between all groups and Prototypes .04 allowed the fastest preparation (p < 0.05). There was no statistically significant association between type of instrument and incidence of aberrations (p > 0.05). The cross-sectional design had a marked impact on the shaping ability of the instruments, and less tapered instruments maintained the original canal curvature better than instruments having greater tapers.

Shaping Ability of Reciproc, WaveOne GOLD, and HyFlex EDM Single-file Systems in Simulated S-shaped Canals

IntroductionThe aim of the present study was to compare the shaping ability of Reciproc (RPC; VDW, Munich, Germany), HyFlex EDM (HEDM; Coltene/Whaledent AG, Altstätten, Switzerland), and WaveOne GOLD (WOG; Dentsply Maillefer, Ballaigues, Switzerland) nickel-titanium (NiTi) files made of different NiTi alloys in S-shaped simulated canals. MethodsSixty S-shaped canals in resin blocks were prepared to an apical size of 0.25 mm using RPC R25, WOG Primary, and HEDM OneFile (n = 20 canal/per group) systems. Composite images were made from the superimposition of pre- and postinstrumentation images. The amount of resin removed by each system was measured using a digital template and image analysis software in 22 different points. Canal aberrations were also recorded. Data were statistically analyzed using the Kruskal-Wallis and post hoc Dunn tests at the 5% level. ResultsNiTi file fracture was not observed during shaping of the simulated canals although a danger zone formation in 1 sample and a ledge in 1 sample were observed in the RPC group. There was no statistically significant difference between the WOG and HEDM groups' apical, medial, and coronal regions (P > .05). However, it was determined that the RPC group removed a statistically significantly higher amount of resin from all the canal regions when compared with the WOG and HEDM groups (P < .05). ConclusionsWithin the limitation of the present study, it was determined that all of the tested NiTi files caused various levels of resin removal. However, WOG and HEDM NiTi files were found to cause a lower level of resin removal than RPC NiTi files.

Evaluation of Effect of Adaptive Motion on Shaping Ability of Twisted File Nickel-Titanium Files in Simulated S-Shaped Canals

Evaluation of Effect of Adaptive Motion on Shaping Ability of Twisted File Nickel-Titanium Files in Simulated S-Shaped Canals

Evaluation of effect of adaptive motion on shaping ability of twisted file nickel-titanium files in simulated S-shaped canals

Evaluation of effect of adaptive motion on shaping ability of twisted file nickel-titanium files in simulated S-shaped canals

Shaping Ability of 4 Different Single-file Systems in Simulated S-shaped Canals

IntroductionThe aim of this study was to compare the shaping ability of 4 different single-file systems in simulated S-shaped canals. MethodsSixty-four S-shaped canals in resin blocks were prepared to an apical size of 25 using Reciproc (VDW, Munich, Germany), WaveOne (Dentsply Maillefer, Ballaigues, Switzerland), OneShape (Micro Méga, Besançon, France), and F360 (Komet Brasseler, Lemgo, Germany) (n = 16 canals/group) systems. Composite images were made from the superimposition of pre- and postinstrumentation images. The amount of resin removed by each system was measured by using a digital template and image analysis software. Canal aberrations and the preparation time were also recorded. The data were statistically analyzed by using analysis of variance, Tukey, and chi-square tests. ResultsCanals prepared with the F360 and OneShape systems were better centered compared with the Reciproc and WaveOne systems. Reciproc and WaveOne files removed significantly greater amounts of resin from the inner side of both curvatures (P < .05). Instrumentation with OneShape and Reciproc files was significantly faster compared with WaveOne and F360 files (P < .05). No instrument fractured during canal preparation. ConclusionsUnder the conditions of this study, all single-file instruments were safe to use and were able to prepare the canals efficiently. However, single-file systems that are less tapered seem to be more favorable when preparing S-shaped canals.

Shaping ability of two M-wire and two traditional nickel-titanium instrumentation systems in S-shaped resin canals.

The aim of this study was to evaluate the shaping effects of two M-wire and two traditional nickel-titanium (NiTi) rotary systems in simulated S-shaped resin canals. Forty simulated S-shaped canals in resin blocks were instrumented with two traditional (ProTaper, Sendoline S5) and two M-wire (WaveOne, GT series X) NiTi systems according to the manufacturers' instructions. Ten resin blocks were used for each system. Pre- and post-instrumentation images were captured using a stereomicroscope and superimposed with an image program. Canal transportation, material removal, and aberrations were evaluated and recorded as numeric parameters. Data were analyzed using one-way ANOVA and post-hoc Tukey tests with a 95% confidence interval. There were significant differences between systems in terms of transportation and material removal (P<0.05). Coronal danger zone was the most common aberration. Within the limits of this ex vivo study, it was found that the manufacturing methods (M-wire or traditional NiTi) and kinematics (rotary or reciprocating motion) did not affect the shaping abilities of the systems. The extended file designs of highly tapered NiTi systems (ProTaper, WaveOne) resulted in greater deviations from the original root canal trace and more material removal when compared to less tapered systems (Sendoline S5, GT series X).

Shaping Ability of Different Nickel-Titanium Systems in Simulated S-shaped Canals with and without Glide Path

IntroductionThe objective of this study was to compare the shaping ability of different rotary and reciprocating nickel-titanium file systems with and without previous glide path preparation in simulated S-shaped canals. MethodsOne hundred twenty S-shaped canals in resin blocks were prepared to an apical size 25 by using Reciproc, WaveOne, HyflexCM, F360, and OneShape systems either with or without previous glide path preparation (Pathfile) (12 canals/group). Material removal was measured at 20 measuring points, beginning 1 mm from the end point of preparation. Incidence of canal aberrations (zip/elbow, ledge formation), preparation time, and instrument failures were also recorded. Statistical analyses were performed by using analysis of variance and Tukey and χ2 tests. ResultsFor all systems, glide path preparation exerted no significant effect on preparation times (P > .05). Glide path preparation had no influence on the incidence of canal aberrations and instrument fractures (P > .05), with no significant differences between the 5 systems (P > .05). Glide path preparation had no influence on the centering ability of all systems (P > .05). On average, canals prepared with F360, OneShape, and HyflexCM remained better centered compared with those enlarged with WaveOne and Reciproc. ConclusionsUnder the conditions of this study, glide path preparation had no significant impact on canal straightening. Less tapered instruments maintained the original canal curvature better than instruments having greater tapers.

Comparision of two different preparation protocol of Ni-Ti Rotary PathFile-ProTaper instruments in simulated s-shaped canals

Introduction. The aim of this study is to compare the root canal transportation with the PathFile-ProTaper recommended protocol, PathFile-ProTaper modified protocol and stainless steel K-flexofiles. Methods. Forty-five ISO 15, 0.02 taper S-shaped Endo Training Blocks were divided randomly into three groups of 15 each and prepared as follows: PathFile-Protaper recommended protocol, Pathfile-Protaper modified protocol and manual preparation with K-Flexofiles. The amount of transportation was assessed by scanning the blocks before and after preparation and superimposing the images. The cutting effects of the instruments from the inner and outer aspects of the root canals were measured and statistically analyzed with the One-way Anova test and Tukey HSD test. Results. Manual preparation caused significantly more transportation than both PathFile-Protaper systems. There was no significant difference regarding transportation between the two Pathfile-Protaper protocols. Conclusion. The modified Pathfile-Protaper protocol transported the canal similar to the recommended Pathfile-Protaper protocol. It may be suggested that, while working safety remains unchanged, the shaping procedure and consequently working time can be shortened with fewer instruments. The results of this study can help clinicians to reduce the preparation time with the PathFile-ProTaper rotary system while the preparation quality remains the same.

Shaping ability of thermomechanically treated files in simulated S-shaped root canals

Aim: the aim of this study was to investigate the shaping ability of thermomechanically treated files manufactured by twisting(Twisted files)and compare it to conventional rotary system (K3, Sybron Endo, Orange, CA) in S-shaped canals, including formation of ledges, zipping, elbow, outer widening, danger zone, perforation and file deformation. Materials & Methods: Forty S-Shaped canals in resin blocks were randomly divided into 2 groups of 20 each. Pre-instrumentation images of the canals were taken via a digital camera and superimposed on images taken after preparation with TF and K3 systems to apical size of 25/06 and 30/06. Canal aberrations were measured from the superimposed image at five levels using AutoCAD system. Fisher exact test and Mann Whitney test were used for analysis of the data. Results: the incidence of zipping, elbow and apical transportation was significantly lower in the TF group (P = 0.04). Generally the incidence of aberration increased when the apical size increased to 30/0.06 regardless of the file system. Significant file deformation was evident in the TF after single use (P ? 0.001). Conclusion: Under the conditions of this study, TF manufactured by new technique performed better than K3 systems when used up to size 25/06 in simulated S-shaped canals. Clinical significance: The flexibility of thermomechanically treated files is beneficial in canals with multiple curvatures; however, attention should be paid to the instrument taper and final apical size of the preparation.

A comparison of the shaping effects of 5 nickel-titanium rotary instruments in simulated S-shaped canals

The objective of this study was to compare the shaping efficacy of 5 Ni-Ti rotary instruments with different cross-sectional designs in simulated S-shaped resin root canals. One hundred canals (n = 20) were instrumented to apical size 0.04/25 with ProFile, K3, NiTi-TEE, EndoWave, or HeroShaper. Pre- and postoperative images were superimposed. Width of resin removal was measured. Total amount of material removal, amount and direction of transportation, and centering ratios were determined. Data were analyzed using 1-way ANOVA and post hoc Tukey and Newman-Keuls multiple comparison tests. In terms of centering ratio and amount of transportation, ProFile followed by K3 gave the best results almost throughout the whole canal. However, ProFile created insufficient taper. Canals instrumented with the other 3 systems were transported and lacked flow. The K3 system, probably owing to its cross-sectional design and sequence encompassing a high number of instruments, seems under the conditions of this study to be a better choice in preparing S-shaped simulated root canals.

Shaping ability of GT series X rotary files in simulated S-shaped canals

Shaping ability of GT series X rotary files in simulated S-shaped canals

Shaping Ability of Four Nickel-Titanium Rotary Instruments in Simulated S-Shaped Canals

Introduction The purpose of this study was to compare the shaping ability of ProTaper, Mtwo, BioRaCe, and BioRaCe + S-Apex instruments in simulated canals with an S-shaped curvature. Methods Canal transportation and aberrations were assessed by comparing the preinstrumentation and postinstrumentation images under a stereomicroscope. Analysis of variance and post hoc Student-Newman-Keuls test were used for statistical analysis. Results ProTaper instruments caused more pronounced canal transportation in the apical curvature ( P < .01) than all other instruments. The use of ProTaper, Mtwo, and BioRaCe instruments resulted in more canal aberrations compared with BioRaCe + S-Apex ( P < .05). Conclusions NiTi systems including less tapered and more flexible instruments like S-Apex seem to be favorable when preparing S-shaped canals.

The Shaping Effect of the Combination of Two Rotary Nickel-Titanium Instruments in Simulated S-Shaped Canals

This study aimed to analyze the ability of ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) combined with Hero642 (MicroMega, Besancon, France) to shape the simulated S-shaped canals. Thirty simulated canals with double curvatures, 30° coronally and 20° apically, were randomly divided into three groups and prepared with different instruments: ProTaper in group 1, Hero642 in group 2, and a combination of ProTaper and Hero642 in group 3. All canals were scanned pre- and postoperatively. Each postinstrumentation image was superimposed with the preoperative one in a computer. The amount of material removed from canal wall after every instrument was measured at 14 points. Statistical analysis was performed by using an analysis of variance test at α = 0.05. Canals prepared with rotary ProTaper were straightened progressively after the use of F1, and great transportation was created. Hero642 and the combination instruments maintained the original shape of canal with a little transportation. However, the taper of canals prepared with Hero642 was relatively poor.

Study of the Progressive Changes in Canal Shape After Using Different Instruments by Hand in Simulated S-Shaped Canals

This study analyzed the progressive changes in canal shape after the use of different instruments by hand in simulated S-shaped canals. Forty simulated canals with double curvatures, 30 degrees coronally and 20 degrees apically, were randomly divided into four groups and prepared with stainless steel K-files, the ProTaper for hand use (PHU) system, NiTi K-files, and the combination of PHU and NiTi K-files, respectively, by hand. All canals were scanned pre-and postoperatively. Each postinstrumentation image was superimposed with the preoperative one in a computer. The amount of material removed after every instrument was measured at 14 points. Statistical analysis was performed using an analysis of variance (ANOVA) test at alpha=0.05. All four instruments straightened the S-shaped canals, except the combination of PHU (S1, Sx, and S2) and NiTi K-files, which created a continuous funnel shape. There was a significant difference in the amount of material removed between S2 and F1 of the PHU system (p<0.05), and the finishing files of PHU created the same transportation as the stainless steel instruments with the same tip size (p>0.05).

The Shaping Effects of Three Nickel-Titanium Rotary Instruments in Simulated S-Shaped Canals

The purpose of this study was to compare the shaping effects of three nickel-titanium rotary instruments, ProTaper, K3, and RaCe, with emphasis on canal transportation. Simulated canals with an S-shaped curvature in clear resin blocks were prepared with a torque-control, low-speed engine. Canals were prepared using the crown-down technique to the size of #30. Canal aberrations were assessed by comparing the pre- and postinstrumentation images under a stereomicroscope. ProTaper instruments caused greater widening of canals compared to K3 or RaCe. Furthermore, ProTaper files showed a tendency to ledge or zip formation at the end-point of preparation. These canal aberrations may be caused by ProTaper finishing files, which appear to be less flexible than other files of the same tip-size, because of their greater taper-size. These results suggest that nickel-titanium file systems including less tapered, more flexible instruments, like K3 and RaCe should be used in the apical preparation of canals with a complicated curvature.