Mtwo Files Research Articles

Surface roughness and cyclic fatigue resistance of a novel shaping system: An in-vitro study.

Recently developed Nickel-Titanium (NiTi) instruments with practical changes have resulted in safer instrumentation. In addition, topographical features on the file surface are a contributing factor to clinical durability. Therefore, this study aimed to investigate both the cyclic fatigue resistance and the roughness change of MTwo and Rotate instruments (VDW, Munich, Germany). Each instrument (n = 6/each group) was scanned with an atomic force microscopy prior to and after instrumentation. In addition, cyclic fatigue testing was conducted for each instrument (n = 11/each group) with stainless-steel blocks, including 45°-60°-90° degrees of curvature milled to the instruments' size. The roughness parameters increased for both systems after instrumentation (p<0.05). Both systems presented an increased roughness following instrumentation (p<0.05). The cyclic fatigue resistance was lowest at 90° for both systems (p<0.05), whereas the Rotate files presented a higher resistance than that of the Mtwo files (p<0.05). Compared to the Mtwo files, Rotate files presented better resistance, while the resistance decreased as the curvature increased.

Optimization of difficult endodontic treatment with nickel-titanium files in martensitic and austenitic phase

INTRODUCTION. Nickel-titanium alloys and cutting-edge design of endodontic files continue to revolutionize. In addition to variations in the design of nickel-titanium files, manufacturers have implemented several proprietary manufacturing processing procedures to improve their mechanical properties.AIM. The aim of the study was to improve the quality of mechanical instrumentation of highly curved root canals based on the data of laboratory and experimental analysis of rotary endodontic instruments made of nickel-titanium alloys of various modifications.MATERIAL AND METHODS. As part of the research, the following endodontic rotary files systems were studied during instrumentation of curved root canals: group 1 – Mtwo (VDW); group 2 – Race Evo (FKG), group 3 – Ultrataper next (Eurofile). A metallographic analysis of the instruments was performed, a morphological structure of the root dentin after instrumental was examined by scanning electron microscopy, as well as the amount of extruded debris was studied.RESULTS. Groups 2 and 3 showed significant deterioration after three applications. Mtwo files showed a statistically higher amount of surface damage after five uses (p &lt; 0.05). The smallest amount of extruded debris was found in the group 2, while the largest number of root dentin irregulations was found in the groups 1 and 3 (p &lt; 0.001).CONCLUSIONS. A different degree of the surface damage of the instruments was revealed, depending on the number of treated root canals. The safest and most effective endodontic system for the mechanical preparation of curved root canals is the Race EVO.

Effect of Sterilization and Irrigating Solutions on Nanostructure Alteration of Ni-Ti Rotary Instruments in Endodontics: An Atomic Force Microscopic Study.

This study aimed to evaluate the effect of 5.25% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA) and sterilization on the nanostructural alteration of nickel titanium (Ni-Ti) rotary file systems in endodontics using the atomic force microscopy (AFM). The study was performed on four commercially available rotary Ni-Ti files: group I-Vortex Blue (Dentsply), group II-ProTaper Next (Dentsply), group III-Mtwo (VDW), and group IV-iRaCe (FKG). Each group was divided into four subgroups (n = 4), that is, subgroup A-control (new rotary file), subgroup B-subjected for five cycles of autoclave, subgroup C-immersed in 5.25% NaOCl for 5 minutes, and subgroup D-immersed in 17% EDTA solutions for 5 minutes. All the specimens were evaluated with AFM using roughness average (RA) and root-mean-square (RMS) values for surface roughness. Among control groups, Vortex Blue showed the least RA and RMS values; the highest surface roughness was seen with Mtwo files. All the Ni-Ti rotary files showed a statistically significant (P <0.05) increase in surface hardness when subjected to autoclave and treatment with different irrigating solutions. In particular, 17% EDTA caused the highest surface deterioration in all the groups. AFM analysis revealed increased surface roughness values recorded for all the rotary files when treated with irrigating solutions and autoclave cycles.

An In Vitro Comparative Assessment of Shaping Capacity of a Single-File System Over Multiple-File System in Root Canals.

The study's objective was to contrast the two distinct rotary file techniques used to shape mandibular first molars. The investigation involved twenty recently removed mandibular molars. A digital single-lens reflex (DSLR) camera was placed in a fixed position, a muffle block was built, and images of each tooth's three cross sections were obtained. The specimens were split into the following two groups at random: Rotary files from WaveOne were used to prepare group A and Mtwo rotary files were used to prepare group B. At the coronal, middle, and apical thirds of the root canals, WaveOne file system demonstrated improved centering ability compared with the Mtwo file system (P 0.05). When compared to the Mtwo file system, WaveOne file system demonstrated improved centering capabilities and needed significantly less time to build the curved canals.

Comparison of Cleaning Efficacy of Different Rotary Files in Primary Teeth-An In vitro Study.

The aim of the present study was to comparatively assess the cleansing efficiency of dissimilar rotary files in deciduous teeth. Forty-five deciduous anterior teeth that had been subjected to extraction were chosen for this research. The teeth were included if they had a minimum of 2/3rd undamaged root portions. Coronal entrée was completed using round diamond burs. All 45 samples were allocated at random to one of the following three groups: Group I: Control group in which the radicular canal was not subjected to any form of instrumentation, Group II: The radicular canal was subjected to instrumentation employing rotary ProTaper files, Group III: The radicular canal was subjected to instrumentation with rotary MTwo files. The samples were subjected to immersion in a succession of diluted ethyl alcohols to permit dehydration: With a change of solution every eight hours, the first 16 hours were spent in 70% alcohol, followed by eight hours in 80% alcohol, eight hours in 95% alcohol, and eight hours in 100% alcohol. The samples thus subjected to dehydration were cleared by immersion in methyl salicylate for six hours. Under a stereomicroscope with a 10x magnification, the root canals were examined by a person who was blinded to the groups in order to look for any traces of ink in the coronal, middle, and apical third of the canals. In the control group, greater residual remains were present in the apical 3rd at 2.16 ± 0.08 followed by the coronal 3rd at 2.02 ± 0.14, and then in the middle 3rd at 1.88 ± 0.10. While using the ProTaper files, greater residual remains were present in the middle portion at 1.68 ± 0.16, followed by the coronal third at 0.94 ± 0.09, then the apical third at 0.98 ± 0.22. Greater residual remains were again noted with the MTwo files in the mid-portion at 1.44 ± 0.18, followed by the coronal part at 0.86 ± 0.10 and then the apical part at 0.82 ± 0.04. Differences among these groups were statistically significant with a P value < 0.001. The present study concluded that either of the file types used exhibited reasonably lower remnant score values in the apical third versus the middle/coronal thirds. Nonetheless, MTwo type files delineated superior capacity at removing debris versus the ProTaper file types at the apical level.

Transportation and Centering Ability of Kedo-S Pediatric and Mtwo Instruments in Primary Teeth: A Cone-beam Computed Tomography Study

BackgroundCleaning and debriding the canals and preserving the shape of the canal without deformation is the primary goals of pulpectomy. Transportation is a critical endodontic iatrogenic fault that could cause a catastrophe. This study evaluated the canal centering ability and canal transportation caused by Kedo-S pediatric and Mtwo instruments, using a cone-beam computed tomography (CBCT).Materials and methodsThis in vitro study was performed on distal roots of 50 primary mandibular first molars. The teeth were scanned using CBCT and randomly divided into two groups. The canals were then prepared using either Kedo-S or Mtwo files (n = 25). The instrumented canals were rescanned. The scanned volumes were sectioned at 2, 4, and 6 mm from cementoenamel junction (CEJ). Canal transportation (CT) and instrument centering ability were estimated and compared in both groups.ResultsThe mean values for two study groups were compared. T -test was used to determine theP value. The Levene's test was used to test the significance between two groups. The two groups showed similar results in terms of transportation and centering ability (P > 0.05).ConclusionKedo-S pediatric and Mtwo instruments demonstrated similar canal centering ability and CTs.How to cite this articleHaridoss S, Rakkesh KM, Swaminathan K. Transportation and Centering Ability of Kedo-S Pediatric and Mtwo Instruments in Primary Teeth: A Cone-beam Computed Tomography Study. Int J Clin Pediatr Dent 2022;15(S-1):S30-S34.

Computed Tomographic Assessment of Remaining Dentin and Risk of Perforation after Kedo-S and Mtwo Rotary Instrumentation in Root Canals of Primary Teeth: An In Vitro Study.

BackgroundRoot canal cleaning is a key step in the endodontic treatment of the primary molars. An innovative generation of endodontic instruments has been devised with the aim of emerging better procedures. The objective of the study is to assess the preparation of time, the risk of lateral perforation, and the removal of dentin from Kedo-S and Mtwo rotary instruments on primary teeth.Study designThis is an in vitro experimental study comparing the two groups.Materials and methodsA total of 50 extracted mandibular primary first molars are collected, divided randomly into two groups of 25 teeth each. Group I: Kedo-S Pediatric rotary file, Group II: Mtwo rotary file. Distal canal is standardized for evaluation and teeth are sectioned at the CEJ. The teeth were instrumented according to manufacturer's guideline. Both the groups are scanned before and after instrumentation of the canal using cone-beam computed tomography (CBCT) and values are evaluated.ResultsCompared with Mtwo files, Kedo-S files need less instrumentation time and limited lateral perforation. No statistical differences were reported between the instrumentation of Kedo-S and Mtwo with regard to the amount of dentin removed.ConclusionIn pediatric endodontics, Kedo-S pediatric rotary file can be considered an effective alternative to traditional rotary files because it requires less instrumentation time and preserves dentin thickness.How to cite this articleSwaminathan K, Rakkesh KM, Haridoss S. Computed Tomographic Assessment of Remaining Dentin and Risk of Perforation after Kedo-S and Mtwo Rotary Instrumentation in Root Canals of Primary Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(S-1):S87-S91.

Comparison of Cutting Efficiency and Safety of 10/0.04 RaCe and Mtwo Rotary File Systems in Reaching the Full Root Canal Working Length: An In Vitro Study

Introduction: Both RaCe and Mtwo rotary systems introduced the 10/0.04 file as the first file used in the root canal (Glide path). This study aims to compare different factors of both the rotary systems, including cutting efficacy, file fracture, topography changes of files, and changes of the root canal. Materials and Methods: In this laboratory study, 12 RaCe and 12 Mtwo files were prepared and tested on 24 resin blocks with 30° curvature. The time to reach the working length was recorded. Topographical changes of the files have been observed with a stereomicroscope if needed. Changes in resin blocks were measured by photographing and using Photoshop software. Data were analyzed through an independent two-sample t test and likelihood-ratio chi-squared test. Results: Time to reach the working length was significantly lower in the RaCe group than in the Mtwo group (3.57 ± 0.56 s vs. 10.33 ± 2.25 s, P < 0.001). File fracture did not occur in any of the two rotary systems. Topographical changes of the files in RaCe group were also less than the Mtwo group (P = 0.032). Conclusion: The RaCe file is faster in reaching the working length. Both files are safe and do not cause drastic changes in the root canal.

Longitudinal craze line propagation in human root dentin after instrumentation with NiTi rotary files of different instrument tapers after long-term chewing simulation

ObjectivesThe aim of this study was to investigate whether file design and taper significantly influence microcrack initiation during machine preparation.Materials and methodsSixty extracted teeth with straight single canals were selected. The teeth were randomly assigned to four groups based on their root canal anatomy and the corresponding NiTi rotary file system (I, Mtwo; II, ProTaper Universal; III, F6 SkyTaper; control, no preparation and filling). The root canals of the experimental groups were filled using the single-cone technique. The tested teeth were all subjected to a mechanical chewing simulation with flat lead loading over a period of 3 years (corresponding to 150,000 cycles). The teeth were checked for dentinal defects (accumulative crack growth in length) under the digital microscope (Keyence VHX-5000) at time 0 (baseline prior to chewing simulation) and after 3, 6, 12, 24, and 36 months of loading. The cumulative crack increase was statistically analyzed using the Kruskal–Wallis test, Jonckheere–Terpstra test, and the Wilcoxon rank-sum test. The significance was set at p < 0.05.ResultsIn contrast to preparation with greater-tapered instruments, ProTaper Universal (group II) and F6 SkyTaper (group III) instrumentation with the smaller tapered Mtwo files (group I) showed less accumulative propagation of craze lines (p < 0.05) at all time points.ConclusionInstruments with greater taper for root canal instrumentation should be used with care to avoid negative long-term effects in the form of propagation of dentinal defects over time. A positive cutting-edge angle and a smaller taper have a positive effect on a lower craze line development.Clinical relevanceInstruments with a positive cutting-edge angle and a smaller taper are beneficial for the long-term preservation of dentinal tooth structure.

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.

A Comparison of Mtwo and RaCe Rotary Instruments in the Preparation of Curved Canals

The aim of this study was to compare the effectiveness of Mtwo and RaCe rotary instruments in cleaning and shaping root canals curvature. The present study was conducted on 160 simulated canals in resin blocks with an angle curvature of 15°-30°. These 160 simulated canals were divided into two groups, where each group consisted of 80 blocks. In the first group, the canals were prepared using Mtwo rotary system (VDW, Munich, Germany). In the second group, the canals were prepared using RaCe instruments (La Chaux-De-Fonds, Switzerland). The data were recorded using SPSS version 23 software (Microsoft, IL, USA). The results obtained by using the Mtwo rotary instruments showed that these instruments were able to clean and shape in the right-to-left motion curved canals, at different levels, without any deviation and in perfect symmetry, with a p value = 0.000. The data showed that greater the depth of the root canal, greater the deviations of the RaCe rotary instruments. These deviations occurred in three levels, which are the following: S2 (p = 0.004), S3 (p = 0.007), and S4 (p = 0.009). The Mtwo files can go deeper and create a greater angle in S4 level (21°-28°) compared to RaCe instruments with an angle equal to 19°-24°. The present study noted a clinical significant difference between Mtwo rotary instruments and RaCe rotary files used for the canal preparation and indicated that Mtwo instruments are a better choice for the curved canals. There are a large number of procedures and instruments used in the preparation of the root canal. Mtwo and RaCe rotary files were the instruments taken under comparison, in order to determine which of them would perform better.

Comparative evaluation of apical extrusion of intracanal bacteria using ProTaper Next, Mtwo, and ProTaper rotary systems: An in vitro study.

Aim:The aim of this study was to evaluate the number of intracanal bacteria extruded apically after instrumentation with three different nickel–titanium rotary instruments.Materials and Methodology:Forty freshly extracted mandibular premolars were selected, access cavities were prepared, and the teeth were mounted in the bacterial collection apparatus. Root canals were contaminated with a suspension of Enterococcus faecalis and incubated for 24 h at 37°C. The contaminated teeth were divided into four groups of 10 teeth each according to the rotary system used for instrumentation: Group 1: ProTaper universal files, Group 2: MTwo files, Group 3: ProTaper Next files, and Group 4: Control group (no instrumentation). Bacteria extruded after preparations were collected into vials. The number of colony-forming units (CFUs) was determined for each sample.Statistical Analysis:The data obtained were analyzed using the one-way analysis of variance followed by post hoc Tukey’s test with a P = 0.05 as the level for statistical significance.Results:The results suggested a statistically significant difference in the number of CFUs between four experimental groups (P < 0.001).Conclusion:Least amount of bacterial extrusion was seen in ProTaper Next Group while more bacterial extrusion was seen in MTwo Group.

Сравнительная характеристика степени апикальной транспортации и центрирующих свойств никель-титановых инструментов в аустенитной и мартенситовой фазах

Abstract. The purpose of this in vitro study was to compare the degree of root channel transport and the level of centering of the three most practical endodontic nickel-titanium rotary systems HyFlex EDM, Protaper NEXT and M-two using conical beam computed tomography data. In total, we selected 45 removed from periodontological indications of the first upper jaw molars with fully formed apical sections for the study. A prerequisite for the study was the presence of МВ1 and МВ2 in the anterior buccal root. We randomized all teeth into 3 groups (n = 15) and prepared samples using the files HyFlex EDM, Protaper NEXT and M-two. We evaluated the centering capacity and volume of channel transport by comparing preoperative and postoperative micro-CT scans. We used ANOVA tests, the classification trees method, and the forecast deviation calculation for statistical analysis. The significance level was at 0.05. The channels prepared by means of HyFlex EDM showed the minimum values of extent of transportation of root canals at all three levels (3, 5 and 7 mm from an apical konstriktion) that it connects with a unique design of cross section of a working part of the tool. Maximum channel transport was with M-two in the coronary (7 mm) and middle (5 mm) third. When analyzing centering abilities, channels prepared using the HyFlex EDM and Protaper NEXT system showed maximum values at all three levels compared to M-two files. The channels prepared by means of HyFlex EDM had the minimum values of transportation of the channel at all three levels of a root canal. Optimal mechanical preparation of root channels for the parameters studied at all levels was achieved using the tools HyFlex EDM and Protaper NEXT.

Removal of Calcium Hydroxide from Artificial Grooves in Straight Root Canals: Sonic Activation Using EDDY Versus Passive Ultrasonic Irrigation and XPendo Finisher

IntroductionThe aim of the present study was to compare sonic activation using EDDY (VDW, Munich, Germany), passive ultrasonic irrigation (PUI), and mechanical activation using the XPendo Finisher (FKG Dentaire, La Chaux-des-Fonds, Switzerland) for the removal of calcium hydroxide from artificial grooves in straight root canals. MethodsThe root canals of 90 human maxillary incisors with straight root canals were prepared using Mtwo files (VDW) up to size 40/.04, and the teeth were split longitudinally. A lateral groove in the apical or coronal part was prepared in each root half and filled with calcium hydroxide, and the root halves were reassembled. Five groups were established according to the removal techniques: group A, the XPendo Finisher; group B, EDDY; group C, PUI; group D, manual irrigation with a syringe; and group E, no irrigation (the control group). The activation procedures were performed for 30 seconds with 3 mL sodium hypochlorite 3% as the irrigant. The cleanliness of the grooves was scored under 10× magnification. The median of scoring was analyzed using the Kruskal-Wallis test (P = .05). ResultsAll activation techniques were significantly more effective in the removal of calcium hydroxide than manual irrigation (P < .05). Regarding the apical groove, EDDY and PUI were significantly more effective in the removal of calcium hydroxide than the XPendo Finisher (P < .05). No difference was found for the coronal groove (P > .05). ConclusionsEDDY and PUI were significantly more effective in the removal of calcium hydroxide than the XPendo Finisher regarding the apical region. Manual irrigation was significantly less effective than all activation techniques.

Comparison between Rotary (Mtwo) and Manual (H-Files) Techniques for Instrumentation of Primary Teeth Root Canals.

The aim of the study is to compare instrumentation time between manual (H-files) and rotary (Mtwo) files along with patient and operator compliance in primary lower molars. 30 primary teeth were selected and divided into two groups of 15 in each group instrumented with H-files and Mtwo files respectively. Time taken for instrumentation was calculated using stop watch. Patient and operator compliance was recorded through questionnaire. Chi Square test was used to compare the distribution of teeth and number of canals. Independent Student t test was used to compare the mean time taken for instrumentation with both techniques in different canals and the mean overall time for instrumentation where P value is less than 0.001. Chi Square Goodness of Fit test was used to compare the patient's and operator's perspective regarding instrumentation techniques. The instrumentation time recorded with Mtwo files is less when compared with H-files. 66.7% children preferred H-files over Mtwo, 60% children reported pain while using H-files, 60% of children were scared on sight of Mtwo rotary system. Operator could manage 80% of children easily while using H-files, but it was found that operator ease of comfort was more with Mtwo rotary system. Time taken for instrumentation with Mtwo files was less as compared to H-files. It was convenient for the operator to manage the child using H-files but with the use of Mtwo files, marked reduction in the instrumentation time was appreciated.

Apical Debris Extrusion by Novel Endostar E5 Compared to Other Commercial Rotary Files: An in Vitro Study

Objective: To compare the amount of apical debris extrusion in samples instrumented by EndoStar E5, ProTaper Universal, and M-two rotary files. Material and Methods: Forty-five freshly extracted non-carious mandibular premolar teeth with single roots and single canals were acquired, and randomly divided into 3 groups (n=15). Samples in Groups 1, 2, and 3 were instrumented using EndoStar E5 (EE5), ProTaper Universal (PTU), and M-two (MTO) rotary file, respectively. Following instrumentation, the debris extruded was collected in pre-weighed Eppendorf tubes and stored in an incubator at 70°C for 5 days. Tubes containing the dry extruded debris were then weighed. One-way analysis of variance was applied to the weights obtained followed by Tukey’s post hoc test for multiple comparison. Results: The mean debris extruded (mg) for the 3 groups were 1.23 (±0.72), 2.16 (±0.66), and 1.39 (±0.86) for EE5, PTU, and MTO respectively. Samples instrumented with PTU were associated with significantly higher debris extrusion (p 0.05). Conclusion: The novel EE5 and M-two rotary files result in less debris extrusion compared to PTU in mandibular premolars.

Comparative evaluation of post-operative pain after pulpectomy with k-files, kedo-s files and mtwo files in deciduous molars -a randomized clinical trial

Objective: Despite the tortuous course of primary root canal system, a paradigm shift occurred from conventional hand files to rotary system, which lead to faster, cost-effective, uniform and predictable fillings. One of the many advantages being, reduction in post-operative pain with the use of rotary system. Many rotary file systems were introduced, with the recent one, the Kedo-S. So the present study aimed to compare and evaluate the post – operative pain after pulpectomy using K-files, MTwo files and Kedo-S files in deciduous molars. Material and Methods: 75 teeth were randomly divided into three groups (group A – K-files, group B - Kedo-S files and group C - MTwo files) for pulpectomy of primary molars. Post – operative pain was assessed every 6,12,24,48 and 72 hours using facial pain scale. Results: 44% of volunteers in K-file group had moderate pain followed by Kedo-S group that is 8% and then MTwo files that is 4%. Conclusion: The least post-operative pain was found in Mtwo group followed by Kedo-S group and K-file group.KeywordsPulpectomy; Post-operative pain; MTwo; Kedo-S.

Assessment of Different Root Canal Preparation Techniques with Rotary Nickel-Titanium Instruments by Novice Students.

This study investigated which preparation strategy for root canals leads to the best technical preparation quality, and moreover, which is perceived to be performed best by novice students. Sixty-four students were recruited to prepare one simulated root canal with each of the following: FlexMaster files (F), Mtwo files (M), and Reciproc files (R). After preparation, the students assessed the different instrument systems through a questionnaire. The technical quality of the root canal preparations was evaluated by the centering ratio of the preparation. A total of 186 prepared root canals were submitted for evaluation. With R, significantly better centered preparations were achieved when compared to M and F (p < 0.001). The students evaluated R faster than M and F, and evaluated F significantly (p < 0.05) slower than R and M. M was rated as the easiest system to learn and to handle, as well as the best at reaching the working length; therefore, it was evaluated as the overall favorite of the students. A difference was found between the students’ perceptions and their achieved technical quality of root canal preparations.

Choice of Rotary Instrument Usage among Endodontists – A Questionnaire Study

The aim of the study is to find the rotary instrument usage and preferred brand of rotary instrument among endodontists working in dental colleges, Chennai. A rotary instrument is used to remove or reduce tooth matter and to shape teeth during endodontic procedure. Rotary instrument includes burs and endodontic files. Various brands of rotary instruments are currently available in the market which includes dentsply protaper, Mtwo, endostar, k3 XF files, Heroshaper etc. The choice of rotary instrument by a dentist is governed by various factors like their efficiency, ductility, sharpness, cross section and flexibility. An online questionnaire based study was conducted among 97 endodontists working in dental colleges in Chennai. A total of 10 questions consisting of both open ended and close ended questions related to usage, preferred brand and properties were included in the questionnaire . Datas were collected from the filled questionnaire and analysed. Descriptive statistics was used. From the study it was reported that 88% of endodontists use rotary instruments for endodontic procedures in their clinical practice. The most preferred brand of rotary instrument used by endodontists is Mtwo (40%) because of its good cutting ability and shaping followed by 20% k3, 18% protaper, 6% heroshaper and 36% combination of different rotary instruments. Majority of the endodontists preferred using rotary instruments and nearly half of them opt to use mtwo file in their clinical practice.

Multidimensional Analysis of Curved Root Canal Preparation Using Continuous or Reciprocating Nickel-titanium Instruments.

Objective:To evaluate transportation (T) and centering ability (CA) of root canal preparations using continuous or reciprocating nickel-titanium endodontic files.Materials and Methods:Ninety-six mesiobuccal root canals of mandibular first and second molars were randomly divided into 6 groups (n=16) according to the rotary file used: 1. ProTaper Next; 2. ProTaper Gold; 3. Mtwo; 4. BioRaCe; 5. WaveOne Gold; 6. Reciproc. Root canals were prepared according to manufacturer’s instructions. Cone beam computed tomography scans were obtained before and after root canal preparation. Measurements were made at six different reference points: 2, 3 and 4 mm from the apex and 2, 3 and 4 mm below furcation in different directions.Results:The greatest Mesiodistal (MD) Transportation (T) was found for Reciproc files (p<0.05), and the greatest buccolingual (BL) T, for Reciproc, ProTaper Gold and ProTaper Next files (p<0.05). The greatest Mesiodistal (MD) Centering Ability (CA) was found for BioRaCe files (p<0.05), and the greatest Buccolingual (BL) CA, for BioRaCe and Mtwo files (p<0.05).Conclusion:All systems produced root canal transportation. No file system achieved perfect CA of root preparation. Reciproc files had the greatest MD T and BL T. BioRaCe files had the greatest MD CA, whereas BL CA was similar for BioRaCe and Mtwo files.