Rotary System Research Articles

Effect of ultrasonic and Er,Cr:YSGG laser-activated irrigation protocol on dual-species root canal biofilm removal: An in vitro study.

The aim of the study was to investigate the disinfecting efficacy of a standardized irrigating solution activated by ultrasonics or laser irradiation on mature dual-species biofilms at different root levels in vitro. Conventional access cavity preparations were done on 160 single-rooted mandibular premolar teeth with single canals. Freshly extracted oral microbial strains of Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, and Candida albicans after biochemical confirmation were used to generate two discrete dual-species microbial inoculums. The sterilized tooth samples were randomly segregated into two groups (n = 80) and inoculated with a mixed inoculum of S. aureus + E. faecalis strains (Group 1) and S. mutans + C. albicans strains (Group 2), respectively. Following the 21-day incubation period under aerobic conditions, the infected specimens in each group were divided into four subgroups (n = 20) and subjected to experimental treatment protocols. This included a positive control (no treatment of biofilms), syringe irrigation alone with TruNatomy needle, passive ultrasonically activated irrigation with 20# Irrisafe tip, and laser agitation of irrigant with Er,Cr:YSGG laser using RFT 2 laser tip. Root canals of experimental specimens (except the control samples) are instrumented with TruNatomy rotary file system using 1:1 mixture of 3% NaOCl and 18% etidronic acid as irrigants. The quantitative assessment of reduction in viable biofilm microbes after treatment was done using colony-forming unit counts and confocal laser scanning microscopy image analysis. The obtained data were analyzed statistically with a significant level set at 0.05. Laser-assisted irrigation has shown a considerably higher mean percentage reduction of microbes compared to ultrasonic agitation and the syringe irrigation showed the least microbial reduction (P = 0.001). No significant difference was noted between the three root regions of ultrasonic and laser groups (P > 0.05), whereas in the syringe groups, apical portions showed higher microbial counts compared to cervical and mid-root regions (P = 0.001). Erbium laser-assisted irrigation has performed superior to ultrasonic agitation against both the experimental dual-species biofilms, while the syringe irrigation showed the least microbial reduction specifically at apical root portions.

Design of positive pulse measurement while drilling system for mine rotary valve mud

Abstract For the drilling of directional wells and horizontal wells, to ensure that the drilling trajectory is drilled in the coal seam in the direction designed before drilling, it is necessary to transmit information without interrupting the drilling process. The drilling fluid pressure pulse is divided into positive pulse, negative pulse, and continuous wave. The positive pulse transmission system with the mechanical structure of the lifting valve is widely used because of its high pulse signal strength and long propagation distance, which can be used in deep wells. With the increase of the information measured in the formation, the lifting valve can not meet the needs of the current information transmission due to the linear motion of the mechanical structure and the low transmission rate. The rotary valve as the pressure signal generation source can improve the pulse generation rate. Therefore, this paper analyzes the working principle and signal generation principle of the rotary valve positive pulse system, and collects the directional data and natural gamma value of the field test.

Intermittent fault detection in nonstationary processes via a Wald‐based control chart

SummaryIn this article, the problem of intermittent fault (IF) detection is investigated for nonstationary processes in the multivariate statistics framework. By combining the moving window technique with maximum likelihood estimation (MLE), the moving window Wald‐based control chart is proposed to realize the detection of IFs in nonstationary processes. The computational efficiency and the convergence properties are discussed for the designed iterative algorithm of MLE. Then, necessary and sufficient conditions are presented to guarantee the detectability of IFs with the consideration of window lengths. Moreover, the alarm delays are analyzed for the appearance and disappearance of IFs. In virtue of the above analysis, the optimal window length is derived by minimizing the supremum of alarm delays. In order to estimate the time of IFs' appearance and disappearance, an algorithm is designed with the inspiration of simulated annealing strategy. Finally, a simulation on rotary steerable drilling tool system is provided to verify the effectiveness of the proposed method.

Cone-beam computed tomography evaluation of shaping ability of kedo-S square and fanta AF™ baby rotary files compared to manual K-files in root canal preparation of primary anterior teeth

BackgroundPediatric rotary file systems were developed to solve manual file limitations. With many systems available, it may be tricky to select the most appropriate one.Aimto assess & compare Kedo-S Square, Fanta-AF™-Baby rotary files with manual K-file concerning removed dentin amount, canal transportation, centric ability & root canal taper using CBCT in primary anterior teeth.DesignExtracted Seventy-five upper primary anterior teeth with intact 2/3 root length were collected and divided into three groups based on root canal instrumentation, group-I: prepared using K-file, group-II: prepared using Kedo-S Square, and group-III: prepared using Fanta AF™ Baby file. The teeth were imaged with CBCT before & following canal instrumentation. Then, the removed dentin amount was calculated at each root-canal level. The Kruskal-Wallis test was utilized to statistically analyze study data.ResultThe difference among the three groups was highly statistically significant at cervical & apical thirds concerning dentin thickness changes on both mesial & distal sides following canal preparation with the least removed dentin in the Kedo-S Square group(P < 0.0001). Regarding transportation & centering ability, a non-significant difference between the three groups was found. 80% of the Fanta AF™ Baby group had good-tapered preparation compared to the Kedo-S Square (72%) and K-file (40%) groups(P < 0.05).ConclusionKedo-S Square was preferable to Fanta-AFTM-Baby & manual K-files in primary root canal preparation.

Investigation of the energetic and exergetic performance of hybrid rotary desiccant-vapor compression cooling systems using different refrigerants

In this study, a desiccant-based hybrid cooling system supported by a vapor compression system and a heat recovery unit (rotary heat wheel) was analyzed from energetic and exergetic perspectives during the daily working hours of an office building in Istanbul to meet the desired comfort conditions. We focus on the impact of different refrigerants; namely R32, R1234yf, R290, R134a, R600a, R245fa, and R717, on hybrid rotary desiccant-vapor compression systems. While the highest electricity consumption was obtained in the system using R1234yf, the lowest electricity consumption was achieved with R717. However, with the effectiveness of the desiccant wheel, the best results were obtained for R1234yf with those pertinent to R717 at the other extreme. Considering the total electricity consumption of the system, the highest energetic and exergetic performance parameters were achieved with the use of R717 as the refrigerant. Compared to R1234yf, the daily average energetic performance parameters obtained with R717 increased by 22.3 % for COPr, 21.8 % for COPel, and 4.7 % for COPth. Similarly, compared to R1234yf, the daily average exergetic performance parameters in R717 presented increases of 13.6 % for COPx,el, 7.5 % for COPx,th, and 8.1 % for ηx.

Sensor fault estimation based on ellipsoid bundles for dynamic point-the-bit rotary steerable systems

The dynamic point-the-bit rotary steerable system (DPRSS) achieves high-performance trajectory control in oil and gas exploitation. However, the sensor faults significantly degrade the reliability of the DPRSS. In this paper, the problem of sensor fault estimation for the DPRSS is investigated. Firstly, the DPRSS is modeled by a descriptor system with unknown but bounded uncertainties, which include measurement noises, model perturbations, and unknown inputs. Next, by integrating the decoupling technique, a sensor fault estimator is put forward based on the ellipsoid bundles. Besides, order reduction and bound calculation methods are proposed to derive intervals of the states and faults. Then, with a defined minimization criterion of the ellipsoid bundle, a sufficient condition is presented to design the parameters of the estimator. Finally, numerical simulations and experiments on a DPRSS prototype are provided to demonstrate the effectiveness of the proposed fault estimation method.

Evaluation of fracture resistance of radicular dentin treated with nanochitosan-loaded calcium hydroxide and nanographene-loaded calcium hydroxide, when used as intracanal medicament: An in vitro study

ABSTRACT Aim: This study aimed to evaluate and compare the effect of using calcium hydroxide (CH) loaded with nanochitosan and nanographene on radicular dentin fracture resistance. Methods: A total of 40 mandibular premolar root canals were instrumented with the ProTaper rotary system. The fracture resistance of radicular dentin was measured with the universal testing machine, following which intracanal medicament was placed for 10 days. CH alone and CH mixed with nanoparticles of chitosan and graphene were used. Not using any intracanal medicament was used as the control. A one-way ANOVA, followed by the post hoc Tukey’s test, was used to compare the results of different groups. Results: The highest mean for the force at compressive stress was seen in the control group, and the least was recorded by CH. Intergroup comparison for Young’s modulus showed a statistically significant difference (P &lt; 0.05) between the control group and CH (P = 0.002); CH and chitosan + CH (P = 0.003) on post hoc analysis. Conclusion: Incorporation of chitosan and graphene nanoparticles in CH when used as intracanal medicament improves the modulus of elasticity and compressive strength of radicular dentin, which in turn improves dentin elasticity and fracture toughness when compared to CH alone.

Comprehensive Assessment of Cyclic Fatigue Strength in Five Multiple-File Nickel-Titanium Endodontic Systems.

The resistance of nickel-titanium endodontic instruments against cyclic fatigue failure remains a significant concern in clinical settings. This study aimed to assess the cyclic fatigue strength of five nickel-titanium rotary systems, while correlating the results with the instruments' geometric and metallurgical characteristics. A total of 250 new instruments (sizes S1/A1, S2/A2, F1/B1, F2/B2, F3/B3) from ProTaper Gold, ProTaper Universal, Premium Taper Gold, Go-Taper Flex, and U-Files systems underwent mechanical testing. Prior to experimental procedures, all instruments were meticulously inspected to identify irregularities that could affect the investigation. Using a stereomicroscope, design characteristics such as the number of spirals, length, spirals per millimeter, and average helical angle of the active blade were determined. The surface finishing characteristics of the instruments were examined using a scanning electron microscope. Differential scanning calorimetry was employed to establish the instruments' phase transformation temperatures, while energy-dispersive X-ray spectroscopy was utilized to analyze the elemental composition of the alloy. The instruments were subjected to cyclic fatigue testing within a stainless steel non-tapered artificial canal featuring a 6 mm radius and 86 degrees of curvature. Appropriate statistical tests were applied to compare groups, considering a significance level of 0.05. The assessed design characteristics varied depending on the instrument type. The least irregular surface finishing was observed in U-Files and Premium Taper Gold files, while the most irregular surface was noted in Go-Taper Flex. All instruments exhibited near-equiatomic proportions of nickel and titanium elements, whereas ProTaper Universal and U-Files instruments demonstrated lower phase transformation temperatures compared to their counterparts. Larger-sized instruments, as well as ProTaper Universal and U-Files, tended to display lower cyclic fatigue strength results. Overall, the design, metallurgical, and cyclic fatigue outcomes varied among instruments and systems. Understanding these outcomes may assist clinicians in making more informed decisions regarding instrument selection.

Cone Beam Computed Tomography Analysis of Post Space in Bifurcated Premolars Using ParaPost and Peeso Reamer Drills

Introduction Core buildups are usually maintained by the usage of posts. Even so, in curved and narrow canals, such as bifurcated premolars, excessive dentin removal during post-space preparation can result in a vertical root fracture or perforation. In order to preserve root canal dentin during post-space preparation of bifurcated premolars, this study examined and analyzed the effects of two widely used drills: Peeso Reamer (Dentsply Maillefer, Ballaigues, Switzerland) and ParaPost (Coltene/Whaledent, Inc., Altstätten, Switzerland). We also examined the risks associated with using Cone-beam Computed Tomography (CBCT). Methods Three operators with varying levels of experience treated a total of 72 removed bifurcated premolars, dividing them into equal groups. The rotary ProFile system (Dentsply Sirona, Charlotte, NC) was utilized for root canal treatments, and gutta-percha size #30/0.4 was used for obturation. Peeso Reamer #2 and ParaPost #1 were then used to prepare the palatal canals. CBCT was used to assess the total mean intracanal spaces of 3 mm, 5 mm, and 7 mm that were measured both preoperatively and postoperatively. To compare the mean dentin thickness within the canal area across all groups, we used analysis of variance testing. We detected complications, like deviations or perforations, using mesiodistal periapical radiographs. Results When utilizing the Peeso Reamer, the mean dentin thickness (0.749 mm) was slightly more than when using the ParaPost (0.736 mm) with p=0.16. There was no significant difference in the mean dentin thickness of the canal area between the Peeso Reamer and the ParaPost drills. The Pesso Reamer drill had fewer complications since it matched the canal configuration, while the Parapost drill removed somewhat more dentin in the canal area. Only seven teeth with minimum deviation from the center of the canal during preparation were produced by the Peeso Reamer drill (20% of teeth having deviation), whereas twenty-one teeth had deviations (72.2% of teeth) and eight had furcal perforations generated by the ParaPost. Conclusion Within the limitations of our study, the Pesso Reamer drill caused little more dentin removal than the ParaPost drill. However, the Peeso Reamer had fewer risks and was safer to use in bifurcated premolars. The ParaPost drill is not recommended in bifurcated premolars due to the high risks of deviation and perforation because they have narrow canals. The selection of an appropriate drill for post-space use in bifurcated premolars is essential for successful patient outcomes.

Closed-loop Koopman operator approximation

This paper proposes a method to identify a Koopman model of a feedback-controlled system given a known controller. The Koopman operator allows a nonlinear system to be rewritten as an infinite-dimensional linear system by viewing it in terms of an infinite set of lifting functions. A finite-dimensional approximation of the Koopman operator can be identified from data by choosing a finite subset of lifting functions and solving a regression problem in the lifted space. Existing methods are designed to identify open-loop systems. However, it is impractical or impossible to run experiments on some systems, such as unstable systems, in an open-loop fashion. The proposed method leverages the linearity of the Koopman operator, along with knowledge of the controller and the structure of the closed-loop (CL) system, to simultaneously identify the CL and plant systems. The advantages of the proposed CL Koopman operator approximation method are demonstrated in simulation using a Duffing oscillator and experimentally using a rotary inverted pendulum system. An open-source software implementation of the proposed method is publicly available, along with the experimental dataset generated for this paper.

Prescribed-time fault-tolerant tracking control for Markov jump nonlinear systems based on saturation dynamics filters

This paper investigates the problem of prescribed-time fault-tolerant tracking control for a class of Markov jump nonlinear systems affected by actuator faults and input saturation. First, a new time-varying constraint function and an error transformation are invoked to transform the original prescribed-time tracking control problem into a tracking control problem with deferred constraint for tracking error. Furthermore, the parameter correction terms are designed, on which a novel Markov jump saturation dynamic filter is constructed to handle the unfavorable effect of input saturation. Meanwhile, the projection operator technique and the norm estimation methodology are integrated to devise adaptive laws to estimate the unknown actuator faults evolving in accordance with the Markov chain. A new prescribed-time fault-tolerant tracking control scheme is put forward that realizes the deferred constraint on the tracking error, which in turn ensures that the tracking error of the system converges to a prescribed accuracy within a prescribed-time. Finally, two simulation examples, one of which implements a prescribed-time fault-tolerant tracking control for rotary steerable drilling tool system, are presented to illustrate the effectiveness and practicality of the developed scheme.

Investigation of purge angle on the air inhomogeneity reduction and energy efficiency improvement of the desiccant wheel dehumidification system

ABSTRACT The rotary desiccant wheel dehumidification system has been extensively applied to achieve deep dehumidification in the modern environment with low humidity ratio. The effect of mixing destruction caused by the temperature and humidity inhomogeneity on the thermodynamic performance of the desiccant wheel deep dehumidification (DWDD) system has not been thoroughly illustrated. This research aims to reduce the mixing destruction and improve the overall energy efficiency of the DWDD system. Numerical analyses were carried out to investigate the mixing destruction characteristics of the deep dehumidification process. The results revealed that the mixing exergy destruction gradually becomes a prominent factor as regeneration temperature and humidity ratio increase under deep dehumidification, and there is a significant temperature and humidity ratio gradient in the transition angles from the regeneration side to the process side. The purge angle is regulated to reduce the average temperature and humidity ratio on the process side and lower the air inhomogeneity. The exergy efficiency of the desiccant wheel can be improved from 44.8% to 73.9% at the regeneration humidity ratio of 20 g/kg under the effective purge angle of 30°, indicating a considerable enhancement of exergy efficiency under the effective purge angle at a high regeneration humidity ratio.

Cryotherapy Treatment Effect on Heat-Treated Nickel-Titanium (NiTi) Rotary Single-File System: An In Vitro Comparative Study by Finite Element Analysis.

Background The use of endodontic files multiple times can cause fatigue in them and can lead to their separation in the root canal. The purpose of this study was to achieve a reduction in cyclic fatigue stress in a newly introduced nickel-titanium (NiTi) rotary single-file system.The study aimed to determine whether cryotherapy could help reduce cyclic fatigue and stress on rotary files after multiple uses during root canal treatment. By utilizing finite element analysis (FEA), the study provided a comprehensive evaluation of how cryotherapy might enhance the performance and longevity of these instruments, ultimately benefiting patients undergoing root canal therapy. Methodology This in vitro comparative studyused scanned plastic teeth with genuine root canal anatomy and FEAto investigate the mechanical response to cyclic fatigue and stress of NiTi rotary file system. The endodontic file (Procodile, Komet) was created through the complex root canal geometries, for which mandibular tooth models were scanned and created by a computer software (IDEAS11 NX; UGSiPlano, TX). The total sample size was 34, divided into two groups, with each group comprising 17 participants (n = 17).The results were analyzed by analysis of variance (ANOVA) test. Results The results revealed that the p-values were more than 0.525, indicating no significant reduction in cyclic fatigue when the NiTi rotary single-file system (Procodile, Komet) was treated with cryotherapy (eight cycles). However, stress reduction was observed in the NiTi rotary single-file system when it was treated with cryotherapy. Conclusion This in vitro comparative study concluded that cryotherapy helps to reduce the stress of NiTi rotary single-file system. Nonetheless, more research is needed to understand the clinical significance of the findings of the current in vitro study.

Investigating Apically Extruded Debris During Pulpectomy with Two Rotary Systems and Hand Files.

The current research set out to examine and contrast the amounts of apically extruded debris produced by two distinct rotary files and hand files used in pulpectomy procedures. Forty-five extracted primary mandibular molars were randomly divided into three groups for instrumentation. Prime Pedo™ files are in Group 1, DXL-Pro Pedo files are in Group 2, and H and K files are in Group 3. Debris that had been apically extruded and collected in preweighed Eppendorf tubes was incubated for five days at 70°C. The weight of the Eppendorf tubes before and after instrumentation was subtracted to get the weight of the debris that was gathered. It was noted that all three groups had significantly different amounts of material ejected from the tip. The groups with the lightest amounts of extruded debris were 1, 2, and 3, in that order. The most debris was extruded from the apex in Group 3. This suggests that rotary files are preferable to hand files because they reduce debris extrusion, which in turn reduces postoperative events following pulpectomy procedures.

An Integrated Multitasking Intelligent Bearing Fault Diagnosis Scheme Based on Representation Learning Under Imbalanced Sample Condition.

Accurate bearing fault diagnosis is of great significance of the safety and reliability of rotary mechanical system. In practice, the sample proportion between faulty data and healthy data in rotating mechanical system is imbalanced. Furthermore, there are commonalities between the bearing fault detection, classification, and identification tasks. Based on these observations, this article proposes a novel integrated multitasking intelligent bearing fault diagnosis scheme with the aid of representation learning under imbalanced sample condition, which realizes bearing fault detection, classification, and unknown fault identification. Specifically, in the unsupervised condition, a bearing fault detection approach based on modified denoising autoencoder (DAE) with self-attention mechanism for bottleneck layer (MDAE-SAMB) is proposed in the integrated scheme, which only uses the healthy data for training. The self-attention mechanism is introduced into the neurons in the bottleneck layer, which can assign different weights to the neurons in the bottleneck layer. Moreover, the transfer learning based on representation learning is proposed for few-shot fault classification. Only a few fault samples are used for offline training, and high-accuracy online bearing fault classification is achieved. Finally, according to the known fault data, the unknown bearing faults can be effectively identified. A bearing dataset generated by rotor dynamics experiment rig (RDER) and a public bearing dataset demonstrates the applicability of the proposed integrated fault diagnosis scheme.

Control of a slender rotary system subjected to dry friction and rub

Control of a slender rotary system subjected to dry friction and rub

An autonomous and high-accuracy gravity disturbance compensation scheme for rotary inertial navigation system

Abstract With the increasing demands for long-endurance and high-accuracy inertial navigation system (INS), gravity disturbance has been identified as one of the major error sources with decisive effects on the performance of INS. To address the problem, this paper proposes an autonomous and high-accuracy gravity disturbance compensation scheme for rotary INS (RINS). The high-accuracy velocity measured by the laser Doppler velocimeter is fused with the angular velocity measured by the gyroscope to obtain navigation parameters, such as velocity, position and attitude, that are not affected by gravity disturbance. The navigation parameters independent of gravity disturbance are matched with the gravity disturbance-related navigation parameters output by RINS, and a measurement model containing gravity disturbance information is obtained. Besides, the intrinsic coupling relationship between gravity disturbance, gravity disturbance rate and gravity disturbance gradient is revealed, and a state-space model is established to accurately reflect the time-varying characteristics of gravity disturbance. Furthermore, the gravity disturbance is estimated and compensated in real-time through the optimal estimation algorithm. The results of vehicle experiments indicate that the gravity disturbance estimation precision of the proposed scheme is better than 2.15 mGal (1σ), and its horizontal position accuracy is better than 50 m at a driving distance of 80 km.

Characterization of rotary valve control vibration system for vibration stress relief applications

To enhance the vibration system characteristic distortion and pressure loss, we propose a novel rotary valve control vibration system. The paper presents the designed structural composition and generation mechanism of the rotary valve control vibration system. It also derives the mathematical model for the rotary valve distribution process and the overall system. The flow field inside the rotary valve is dynamically simulated using the multiple reference frame model, allowing for the determination of the change rule of the rotary valve’s output characteristics. An AMESim model was developed to analyze the vibration characteristics of the rotary valve control system. The effects of parameters such as inlet pressure, motor speed, and oil supply pump displacement were investigated. A rotary valve control vibration system experimental bench was constructed to experimentally verify the output characteristics of the rotary valve and the vibration characteristics of the system. The results indicate that the characteristic curve of the designed vibration system closely resembles a sinusoidal wave. Additionally, the rotary valve exhibits low pressure loss, making it more suitable for vibration stress relief applications. By appropriately increasing the inlet pressure and decreasing the motor speed, the vibration characteristics of the system can be improved.

Effectiveness of H-files and Pro-Taper universal systems in removing Gutta-percha during endodontic retreatment: A comparative study

ObjectiveThis research was aimed at assessing the effectiveness of manual H-files versus a combination of a Pro-Taper universal rotary canal preparation system and retreatment system in removing gutta-percha (GP) during endodontic retreatment, by using a digital radiography technique. MethodsThis ex vivo study used a non-probability consecutive sampling technique. The study sample comprised 60 extracted anterior permanent teeth, each with one root with a straight root canal (RC). After preparation, RCs were obturated with GP and sealer. Subsequently, teeth were stored for 2 weeks in a humid environment at 37 °C. Thirty teeth each were randomly assigned to the control (group I), and experimental (group II) groups. GP removal was performed with H-files {group I) or a combination of a Pro-Taper universal rotary canal preparation system and retreatment system (group 2). Digital radiographs were acquired with Carestream digital radiovisiography software (Kodak; version-VER.6.10.8.3-A), and the presence of residual GP was analyzed. AutoCAD (2006) software was used to demarcate the RC and residual root filling. The residual GP in both groups was compared with independent sample t-tests. ResultsThe remaining root filling did not significantly differ when GP was removed with conventional Hedstrom files versus a combination of Pro-Taper Universal preparation and retreatment file systems. The residual GP was confined to the apical third of the canals in both groups. ConclusionsPro-Taper Universal preparation and retreatment file systems have similar effectiveness to manual H-files in GP removal in straight canals.

Deviation of Root Canal Curvature Using Three Types of Rotary Instruments: An In Vitro Study

One of the essential requirements for a successful endodontic treatment is efficient cleaning and shaping. Since its introduction, the nickel-titanium rotary system has gained popularity due to its elasticity and suppleness in the creation of curved root canals. To assess the deviation in root canal curvature in severely curved root canals following three different rotary file system preparations. Thirty-six human permanent mandibular first molars were chosen and stored in regular saline after being newly extracted with the curve mesial root. To standardize length at 13 mm, the mesial roots were separated from the tooth and the crown was removed. The three groups of teeth were A, B, and C. Groups A, B, and C were equipped with rotary variable taper instruments, reciprocating variable taper instruments, and rotary constant taper control memory instruments, respectively, in their mesio buccal canals. The instruments were never pressed apically; instead, they were employed in the canal with a constant, gentle passive movement. With frequent and copious irrigation using 5.25% sodium hypochlorite solution and 17% ethylene diamine tetra acetic acid, all canals were shaped and cleansed. To assess the curvature deviation, periapical radiographs were taken both before and after preparation. By using the Schneider method to measure the pre- and post-instrument canal curvatures, the deviation was found. The Wilcoxon test was employed for numerous pairwise comparisons across distinct groups, and the Kruskal-Wallis test was used to conduct statistical analysis among three groups. The p-value of less than 0.05 was deemed statistically significant. Compared to groups A and B, group C had the least variation of canal curvature. The current study concludes that a 4% rotating constant taper control memory instrument works better than a rotary variable taper instrument or a reciprocating variable taper instrument for shaping a curved canal.