Nickel-titanium Rotary File Systems Research Articles

Comparative evaluation of cyclic fatigue resistance of thermomechanically treated NiTi rotary instruments in simulated curved canals with two different radii of curvature: An in vitro Study.

This study aimed to compare the effect of heat treatment on the cyclic fatigue resistance of three different nickel-titanium rotary file systems: TruNatomy, HyFlex CM, and NeoEndo flex in simulated curved canals at two different radii of curvatures. A total of 60 NiTi rotary files of three types were used, and the samples were divided into three groups TruNatomy, HyFlex CM, and NeoEndo flex. All the instruments were subjected to cyclic fatigue testing using a stainless steel custom-made canal model with a 60° angle of curvature and two radii of curvature 5 mm and 3 mm; the number of cycles to fracture and length of the fractured segment was measured. The separated instruments were subjected to fractographic analysis under scanning electron microscope. The number of cycles to failure to fracture a file at a 3 mm radius of curvature is significantly less as compared to a 5 mm radius of curvature (HCM > TRN > NE). Within the limitation of the present study, there was a positive correlation between the radius of curvature and fatigue life of NiTi files.

Comparative Evaluation of the Incidence of Dentin Microcracks Following Biomechanical Preparation Using Four Different Nickel-Titanium Rotary File Systems: An In Vitro Study.

Biomechanical preparation has gotten easier over time with the development of nickel-titanium (NiTi) rotary instruments. Despite their benefits, research has shown that these files frequently result in microcracks in the root canal dentin, which can fracture the roots. Such mishaps should be prevented, as they compromise the integrity of the root and reduce the long-term survival of endodontically treated teeth. This study was conducted at Government Dental College and Hospital, Patiala, Punjab, India. Eighty permanent mandibular premolar teeth were included. All the roots were inspected for any pre-existing cracks or craze lines under a stereomicroscope. The teeth were decoronated and then divided into four groups (n = 20): Group I: TruNatomy, Group II: Neoendo Flex, Group III: ProTaper Gold, and Group IV: 2Shape. The samples were instrumented according to the group to which they belonged. The roots were then sectioned horizontally at 3 mm and 6 mm from the apex and examined under a stereomicroscope at 40xfor the presence of microcracks. The data were analyzed using the IBM SPSS Statistics for Windows, version 26 (released 2019; IBM Corp., Armonk, New York, United States). A chi-square test was applied, and the level of significance was set at p < 0.05. The highest incidence of microcracks was associated with ProTaper Gold (65%), followed by Neoendo Flex (45%), TruNatomy (20%), and 2Shape (20%). All rotary instruments resulted in dentinal damage. ProTaper Gold exhibited the highest frequency of dentin cracks. TruNatomy and 2Shape exhibited satisfactory results with minimal crack formation.

Efficacy of three Nickel Titanium rotary file systems in removal of intracanal filling material (In vitro study)

Efficacy of three Nickel Titanium rotary file systems in removal of intracanal filling material (In vitro study)

An in vitro comparative evaluation of dentinal crack formation caused by three different nickel-titanium rotary file systems in primary anterior teeth.

Cleaning and shaping of the canals damages the root dentin which becomes a gateway to dentinal cracks and thereby causes failure of the treatment. The aim of this study was to assess and compare dentinal crack formation caused by three different nickel-titanium (NiTi) rotary file systems in primary anterior teeth. The present in vitro study is an experimental, comparative study. One hundred fifty extracted primary anterior teeth were included in this study. The teeth were randomly divided into five groups. Group 1: Pedoflex rotary file system, Group 2: Prime Pedo™ rotary file system, Group 3: Kedo-S2 rotary file system, Group 4: K-files, and Group 5: no instrumentation. Roots were sectioned and viewed under a stereomicroscope for the presence of any cracks. The data were analyzed using the Chi-square test and Kruskal-Wallis test. In the coronal, middle, and apical thirds, Group 2 showed a maximum number of crack formations in the middle third (57%), followed by Group 3 (43.3%) and Group 1 (36.7%). Groups 4 and 5 showed no crack formation in all the root sections. The middle third showed a maximum number of crack formations compared to the coronal and apical thirds. Rotary systems render various benefits with an acceptable success in comparison to conventional hand instrumentation. Within the limitation of this study, it was found that Pedoflex rotary file system was the best with the least number of crack formations.

Microleakage of five separated nickel-titanium rotary file systems in the apical portion of the root canal

The aim of this study was to evaluate the rate of apical microleakage following the fracture of five types of nickel-titanium rotary file systems (ProTaper Universal, Mtwo, RaCe, Revo-s, HeroShaper) in the apical one-third of the canal. In this laboratory experiment, 49 mandibular premolars were collected and randomly divided into seven groups. Root canal treatment was performed by five different rotary file systems with different cross-sections. All files, except in the control groups, were scratched at the 3-mm end by a handpiece. After separation of the apical end of the file in the root canal, the apical seal was measured, using the fluid infiltration technique. Data were analyzed in SPSS, using one-way ANOVA and Tamhane's T2 tests at P < 0.05. The Hero Shaper and RaCe files showed the highest (3.14 μL/min) and the lowest (2.51 µL/min) rates of microleakage over time, respectively. There were significant differences between the Hero Shaper and RaCe files and between Hero Shaper and ProTaper files in terms of microleakage (Tamhane's T2 tests, P < 0.05). The presence of a separated file and its cross-section type affects the apical microleakage.

Comparison of cyclic fatigue resistance of different and novel heat-treated nickel-titanium rotary file systems at the intracanal temperature

Aim: The aim of this study was to compare the cyclic fatigue resistance of different heat-treated nickel-titanium rotary systems at intracanal temperature. &#x0D; Methodology: A total of 90 OneCurve (Micro-Mega, Besançon, France), VDW.ROTATE (VDW Dental, Munich, Germany), Typhoon (Clinician’s Choice, New Milford, CT, USA), HyFlex EDM (Coltene/Whaledent AG, Altstatten, Switzerland), and EndoArt Gold and Blue (Inci Dental, Istanbul, Turkey) (n = 15) rotary files (#25/0.06) were tested at intracanal temperature (35.5 ℃) using a dynamic model in a stainless-steel artificial canal with an inner diameter of 1.5 mm, 60° angle of curvature, and 2 mm radius of curvature. Testing was conducted until fracturing, at which time the device stopped automatically, and the number of rotations was calculated as seconds. Lengths of fractured parts were measured using a digital caliper. One-way ANOVA test followed by Tukey’s test was used to compare the groups. Scanning electron microscopic evaluation was performed to confirm the types of fracture.&#x0D; Results: EndoArt Blue group had a significantly higher mean time to fracture in all groups, followed by the HyFlex EDM, VDW.ROTATE, OneCurve, EndoArt Gold, and Typhoon. In addition, the HyFlex EDM and VDW.ROTATE groups had no significant differences between each other and were significantly better than the others. No significant differences were found between the OneCurve, EndoArt Gold, and Typhoon groups (p&gt;0.05).&#x0D; Conclusion: This is the first study in the literature for EndoArt NiTi files and the second study for VDW.ROTATE that evaluated cyclic fatigue resistance. Novel EndoArt Blue files exhibited significantly greater cyclic fatigue resistance than the other NiTi files.&#x0D; &#x0D; How to cite this article: Güneç HG, Keskin NB, Haznedaroğlu F. Comparison of cyclic fatigue resistance of different and novel heat-treated nickel-titanium rotary file systems at intracanal temperature. Int Dent Res 2021;11(3):158-64. https://doi.org/10.5577/intdentres.2021.vol11.no3.4&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Comparative evaluation of sterilization- and temperature-dependent cyclic fatigue resistance of four different nickel-titanium rotary file systems with reciprocal motion

Aim: The aim of this study was to examine the effect of sterilization and temperature differences on the cyclic fatigue resistance of WaveOne Gold, Reciproc, Reciproc Blue, and Twisted File Adaptive rotary file systems. Methods: In total, 160 files and four file systems were used (n = 20). This study was carried out at two different temperatures: 20°C and 39°C. An artificial stainless-steel canal was used for the static cyclic fatigue test. The breaking times of the files were recorded and calculated by multiplying the number of revolutions by the rotational speed. The SPSS 22 program was used for statistical analysis. The Shapiro–Wilk test was used for data with a normal distribution. The Mann–Whitney U test was used for paired groups. The Kruskal–Wallis test was applied to groups with more than two variables where the data did not fit a normal distribution. Tukey’s post-hoc analysis was used to determine the source of differences. A value of p&lt;0.05 was considered statistically significant. Results: When the lengths of the broken pieces and the numbers of breaks were compared at the two different temperatures, there was a significant difference between all the files. In addition, there was a significant between-group difference between the sterilized files and nonsterilized files (p &lt; 0.05). Conclusion: The cyclic fatigue resistance of the Reciproc Blue file was higher than that of the other files. Low temperature increased cyclic fatigue resistance. How to cite this article: Çelikel B, Öztekin F. Comparative evaluation of sterilization and temperature-dependent cyclic fatigue resistance of four different nickel-titanium rotary file systems with reciprocal movement. J Med Dent Invest 2021;2:e211038 https://doi.org/10.5577/jomdi.e211038 Linguistic revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English. Checked for plagiarism: Yes

Cone-beam Computed Tomographic Analysis of Canal Transportation and Centering Ability of Three Different Nickel-Titanium Rotary File Systems

AIM: The aim of the present study was to compare the canal transportation and centering ability of three rotary nickel-titanium file systems, HyFlex controlled memory, Revo-S, and Mtwo in moderately curved root canals using computed tomography (CT). MATERIALS AND METHODS: Thirty freshly extracted single-rooted teeth having curved root canals with at least 10°–20° of curvature were selected. The teeth were divided into three experimental groups of ten each. After preparation with HyFlex CM (Coltene-Whaledent, Allstetten, Switzerland), Revo-S (Micro-Mega, Besançon, France), and Mtwo (VDW, Munich, Germany) all teeth were scanned using CT to determine the root canal shape. Pre- and post-instrumentation images were obtained at three levels, 3 mm apical, 9 mm middle, and 15 mm coronal above the apical foramen were compared using CT software. Amount of transportation and centering ability were assessed. The three groups were statistically compared with analysis of variance and post-hoc Tukey’s honestly significant difference test. RESULTS: Least apical transportation and higher centering ability were seen in HyFlex CM file system in all the three sections followed by Revo-S, Mtwo file system showed maximum transportation. CONCLUSIONS: According to the present in-vitro study, we can conclude that HyFlex CM rotary file systems showed least canal transportation and highest centering ability as compared to Revo-S and Mtwo file system but there was no statistically significant difference among these file systems (p &gt; 0.05) at coronal, middle, and apical level of root canal.

Analysis of the cutting efficiency of two different nickel–titanium rotary file systems: An in vitro study

Aim: The aim of this study was to evaluate and compare the cutting efficiency using two rotary nickel–titanium file systems. Materials and Methods: Thirty-two resin endo training blocks (ETBs) were divided into two groups (16 for each group). Two groups of resin blocks were instrumented using two continuous rotary nickel–titanium instruments (NeoEndo Flexfile and Blueflex Acerfile). The cutting efficiencies of instruments were quotients of the loss weights of specimens, and the time needed for instrumentation. Results: Cutting efficiency of NeoEndo Flexfile was greater than that of Blueflex Acerfile on both resin root canals (P < 0.05). Conclusion: NeoEndo Flexfile instrument was more efficient than Blueflex Acerfile on root canals.

Comparison of In Vitro Torque Generation during Instrumentation with Adaptive Versus Continuous Movement

IntroductionThe purpose of this in vitro study was to compare the torque generated by continuous and adaptive movements of 2 nickel-titanium rotary file systems. MethodsForty-five simulated resin blocks with an S-shaped canal were randomly divided into 3 groups (n = 15) according to the file system and kinematics: the K3XF rotary system (Kerr Endodontics, Orange, CA) with continuous rotary movement, the K3XF with adaptive movement, and the Twisted File (Kerr Endodontics) adaptive file with adaptive movement. After creating a glide path, the canal was instrumented to the same size (.04/#20 for K3XF or SM1 for the Twisted File with adaptive movement) before torque measurement. During the final instrumentation procedure with the .06/25 sized file (K3XF or SM2), the generated torque and the preparation time were recorded. The total torque experienced and the maximum torque value were calculated. The data were statistically analyzed using 1-way analysis of variance and the Tukey post hoc comparison test at a significance level of 95%. ResultsThe K3XF file system used with adaptive motion group showed significantly lower total and maximum torque values compared with the K3XF with continuous rotary movement group. The Twisted File adaptive file with adaptive motion showed significantly lower torque generation and shorter preparation time than the K3XF groups with adaptive or continuous rotation (P < .05). ConclusionsUnder the conditions of this study, adaptive movement for nickel-titanium files may reduce torque generation without increasing preparation time. Nickel-titanium files with a smaller cross-sectional area using adaptive movement may be helpful to reduce the potential risk of root dentin damage.

Cone-beam computed tomography analysis of canal transportation and centering ratio of fifth-generation nickel-titanium rotary file systems in curved root canals

Aim: The aim of this study is to compare canal transportation and centering ratio using of Protaper Next (PTN) (Dentsply Maillefer, Ballaigues, Switzerland) and Revo-S (RS) (MicroMega, Besancon Cedex, France) compared to Protaper Universal (PTU) (Dentsply Maillefer, Ballaigues, Switzerland) nickel-titanium rotary file systems in curved root canals using cone-beam computed tomography. Materials and Methods: Ninety maxillary mesiobuccal first molar uncalcified canals with mature apex, curvature of 20°–45° (the Estrela method) and minimum 20-mm length were selected. The samples were randomly divided into three groups of 30 teeth each, respectively, Group I PTU, Group II PTN, and Group III RS Rotary systems and Instrumented according to the manufacturers' instructions. Pre- and post-instrumentation cone-beam tomographic scan was performed in same position to calculate canal transportation and centering ability at 2 mm, 5 mm, and 8 mm from the root apex. Statistical analysis was performed with ANOVA and Post-hoc Tukey test. Results: PTU had maximum mean canal transportation and minimum mean centering ratio at all levels, whereas PTN showed minimum mean canal transportation and maximum mean centering ratio. The results were statistically significant. Conclusions: In terms of canal transportation and centering ratio in the middle and coronal third of the root, PTN and RS performed better than PTU. However, in apical third, PTN performed best among all other groups.

Comparative evaluation of the shaping ability of rotary systems of varying metallurgy in curved canals and its analysis using cone-beam computed tomography: An in vitro study

Background: This study compared the shaping ability of four nickel-titanium rotary file systems of varying metallurgy along curved canals. Aim: The aim of the present study is to compare the shaping ability of rotary systems of varying metallurgy in curved canals and its analysis using cone-beam computed tomography (CBCT). Materials and Methods: Forty mesiobuccal canals of mandibular first molars with an angle of curvature ranging from 20° to 40° were divided according to the instrument used in canal preparation into four groups of 10 samples each: Hyflex CM (Group I), Vortex Blue (Group II), Flexicon (Group III), and K3XF (Group IV). All samples were instrumented according to the manufacturer's guidelines and prepared to size 30, 0.06-taper master apical file. Canals were scanned and evaluated using an NNT CBCT unit before and after preparation at different levels from the apex. The data were subjected to statistical analysis. Statistical Analysis: The intergroup comparison in terms of canal transportation and the time taken for canal preparation was done by the one-way analysis of variance (ANOVA) test with Bonferroni post hoc test. The intragroup comparison in terms of canal transportation was done by the repeated measures ANOVA test with the post hoc Bonferroni test. For the canal-centering ability, the Kruskal–Wallis test with Mann–Whitney U-test was used for the intergroup comparison and the intragroup comparison was done by Friedman's test with Wilcoxon signed-rank test. Results: Hyflex CM and Vortex Blue files showed significantly least canal transportation and highest canal-centering ability values as compared to Flexicon and K3XF file systems. Conclusion: The metallurgy and file design of Hyflex CM and Vortex Blue file systems resulted in superior shaping ability, with the instruments remaining more centered in the canal than Flexicon and K3XF.

Evaluation of dentinal micro-cracks caused by the Protaper Universal, Protaper Next and Reciproc rotary file systems used in root canal preparation

Objective: In this study, we compared the occurrence of dentinal micro-cracks after use of the ProTaper Universal (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next (Dentsply Maillefer), and Reciproc (VDW, Munich, Germany) nickel–titanium rotary file systems in root canal preparation.&#x0D; Method: One hundred mandibular anterior teeth were divided into five groups of 20 specimens each. Group 1 served as a control, with no intervention. In group 2, preparation was performed using the step-back technique and K files. In groups 3–5, root canal preparation was performed using the ProTaper Universal, ProTaper Next, and Reciproc file systems, respectively. Following preparation, specimens were sectioned at 3, 6, and 9 mm using a Minitom precision cut-off machine. The sections were evaluated under a stereomicroscope. The following scoring system was used to rate specimens: 1, no micro-crack; 2, incomplete micro-crack; and 3, vertical root fracture. The results were statistically assessed (p ≤ 0.05).&#x0D; Results: No micro-crack formation was observed in groups 1 and 2. The highest rate of micro-crack formation was observed in specimens prepared with the ProTaper Universal file system (20%), followed by those prepared with the Reciproc (11.7%) and ProTaper Next (6.7%) file systems. However, no significant difference was detected among groups (p &gt; 0.05). In the groups ProTaper Universal and Reciproc files were used, 1 vertical root fracture was found in 9 mm sections for each.&#x0D; Conclusion: Considering the limitations of in vitro studies, we can conclude that all rotary file systems used in this study led to dentinal micro-crack formation in roots. The ProTaper Universal file system caused more dentinal micro-cracking than did the ProTaper Next and Reciproc file systems.

Farklı Nikel Titanyum Döner Eğe Sistemleri ile Şekillendirme Sonrası Görülen Dentin Defekti İnsidansı

Amaç: Revo-S, ProTaper Next ve Twisted File Adaptif NiTi eğelerinin mandibuler keser dişlerin kök kanallarının şekillendirilmesi sırasında dentin defekti oluşturma sıklıklarının karşılaştırılmasıdır. Gereç ve Yöntemler: Yüz yirmi adet kök ucu gelişimi tamamlanmış, düz köklü mandibuler keser diş çalışmaya dâhil edildi. Otuz diş herhangi bir işlem yapılmadan negatif kontrol grubu olarak ayrıldı. Doksan diş her bir grupta 30 adet olacak şekilde üç gruba ayrıldı; ProTaper Next (PTN), Revo-S ve TF Adaptif (TFA) kullanılarak kök kanalları prepare edildi. Örneklerden su soğutması altında, dişin uzun aksına dik olacak şekilde apeksten 3, 6 ve 9 mm uzaklıkta üç adet kesit elde edildi. Elde edilen kesitler stereomikroskop altında x25 büyütme ile dentin defekti varlığı yönünden incelendi. Elde edilen veriler ki-kare testi kullanılarak istatistiksel olarak analiz edildi (p<0,05). Bulgular: Test edilen bütün NiTi eğe sistemlerinin kontrol grubuna göre istatistiksel olarak daha fazla dentin defekti oluşturduğu saptanmıştır (p<0,05). TFA sisteminin PTN ve Revo-S grubuna göre istatistiksel olarak daha az dentin defekti oluşturduğu bulunmuştur (p<0,05). Farklı seviyelerden alınan kesitler ile dentin defekti miktarı arasında bir korelasyon saptanmamıştır (p>0,05). Sonuç: Çalışmamızda test edilen bütün NiTi eğelerin kök kanal dentininde defekte neden olduğu bulunmuştur. TFA sisteminin PTN ve Revo-S grubuna göre istatistiksel olarak daha az dentin defekti oluşturduğu bulunmuştur.

Incidence of apical crack formation and propagation during removal of root canal filling materials with different engine driven nickel-titanium instruments.

ObjectivesTo determine the incidence of crack formation and propagation in apical root dentin after retreatment procedures performed using ProTaper Universal Retreatment (PTR), Mtwo-R, ProTaper Next (PTN), and Twisted File Adaptive (TFA) systems.Materials and MethodsThe study consisted of 120 extracted mandibular premolars. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the negative control group. One hundred teeth were prepared, obturated, and then divided into 5 retreatment groups. The retreatment procedures were performed using the following files: PTR, Mtwo-R, PTN, TFA, and hand files. After filling material removal, apical enlargement was done using apical size 0.50 mm ProTaper Universal (PTU), Mtwo, PTN, TFA, and hand files. Digital images of the apical root surfaces were recorded before preparation, after preparation, after obturation, after filling removal, and after apical enlargement using a stereomicroscope. The images were then inspected for the presence of new apical cracks and crack propagation. Data were analyzed with χ2 tests using SPSS 21.0 software.ResultsNew cracks and crack propagation occurred in all the experimental groups during the retreatment process. Nickel-titanium rotary file systems caused significantly more apical crack formation and propagation than the hand files. The PTU system caused significantly more apical cracks than the other groups after the apical enlargement stage.ConclusionsThis study showed that retreatment procedures and apical enlargement after the use of retreatment files can cause crack formation and propagation in apical dentin.

Single file reciprocating technique using conventional nickel–titanium rotary endodontic files

This study was aimed to evaluate the applicability of a reciprocating movement technique with conventional nickel-titanium files for root canal preparation. Forty-four simulated canals in resin blocks were used in this study and divided as following four groups according to the instruments used and preparation methods. Group CP (n = 12) and CR (n = 12) were instrumented with continuous rotation using four files of ProFile and RaCe, respectively. Group RP (n = 10) and RR (n = 10) were instrumented with a reciprocation movement by using a single ProFile and RaCe file, respectively. The resin blocks were scanned before and after instrumentation, and the images were superimposed. To compare the efficiency of canal shaping, the preparation time, and centering ratio were calculated. Morphologic changes of tested files were examined by scanning electron microscopy (SEM). Data were analyzed by ANOVA and Duncan's post hoc test at p < 0.05. The preparation time was markedly shorter in Groups RP and RR than in Groups CP and CR. No significant difference in the centering ratio was noted between groups. Although the files used for Groups CP and CR showed no distortion under the SEM evaluation, the files used for Groups RP and RR had considerable torsional distortion. This study suggests that the reciprocating instrumentation technique using conventional nickel-titanium rotary file systems might have a comparable efficacy for the root canal shaping with reduced shaping time. Although the reciprocating technique seems to be an effective alternative to the conventional rotation technique, the risk of torsional distortion and fracture should be considered before clinical application.

Comparison of screw-in effect for several nickel-titanium rotary instruments in simulated resin root canal

Screw-in effect is one of the unintended phenomena that occurs during the root canal preparation with nickel-titanium rotary files. The aim of this study was to compare the screw-in effect among various nickel-titanium rotary file systems. Six different nickel-titanium rotary instruments (ISO 20/.06 taper) were used: (SybronEndo, Glendora, CA, USA), (VDW GmbH, Munchen, Germany), NRT with safe-tip and with active tip (Mani Inc., Shioya-gun, Japan), ProFile (Dentsply-Maillefer, Ballaigues, Switzerland) and ProTaper (Dentsply-Maillefer, Ballaigues, Switzerland). For ProTaper, S2 was selected because it has size 20. Root canal instrumentations were done in sixty simulated single-curved resin root canals with a rotational speed of 300 rpm and single pecking motion. A special device was designed to measure the force of screw-in effect. A dynamometer of the device recorded the screw-in force during simulated canal preparation and the recorded data was stored in a computer with designed software (LCV-USE-VS, Lorenz Messtechnik GmbH, Alfdorf, Germany). The data were subjected to one-way ANOVA and Tukey's multiple range test for post-hoc test. P value of less than 0.05 was regarded significant. ProTaper produced significantly more screw-in effects than any other instruments in the study (p produced significantly more screw-in effects than , and ProFile (p , NRT, and ProFile (p > 0.05), and between NRT with active tip and NRT with safe one neither (p > 0.05). From the result of the present study, it was concluded, therefore, that there seems significant differences of screw-in effect among the tested nickel-titanium rotary instruments. The radial lands and rake angle of nickel-titanium rotary instrument might be the cause of the difference.

Radiographic evaluation of root canals prepared by various nickel-titanium rotary file systems and obturated by the warm gutta-percha method

Radiographic evaluation of root canals prepared by various nickel-titanium rotary file systems and obturated by the warm gutta-percha method

Canal-Centering Ability of Two Rotary File Systems

The ability of two nickel-titanium rotary file systems to maintain the original path of the canal were compared by using a new split-mold design (the Endodontic Cube). The mesial roots of 10 mandibular first- and second-molar teeth with separate canals from orifice to foramen were divided into two groups based on canal curvature and morphology. Working lengths for each canal were determined 1.0 mm short of where the file tip was visible on the external surface of the root. The teeth were embedded in composite resin by using the Endodontic Cube as a mold and sectioned into five pieces. ProFile Ni-Ti.06 taper Series 29 and ProFile GT rotary instrumentation techniques were randomly assigned to one of the canals and used in a crown-down fashion to a 0.217 ProFile and a 0.06 GT master apical file, respectively. Digital photographs were made of the middle three sections and software features of Adobe Photoshop were used to measure the movement of the canal centers by superimposing the images of the instrumented and uninstrumented canals. Data were analyzed using ANOVA. Both systems remained centered within the canal with minimal deviation from the original canal path. The largest mean movement was less than 0.15 mm. The Endodontic Cube was an effective tool for studying and comparing instrumentation techniques.