1
|
Jeong HY, Ha JH, Sigurdsson A, Peters OA, Kim HC, Kwak SW. Effects of Side Flattening on Torsional and Cyclic Fracture Resistance of Nickel-Titanium File. J Endod 2024:S0099-2399(24)00234-6. [PMID: 38642733 DOI: 10.1016/j.joen.2024.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 04/22/2024]
Abstract
INTRODUCTION The purpose of this study was to evaluate the effect of side flattening of cutting flutes on the cyclic resistance and torsional resistance of nickel-titanium files. METHODS Both novel flattened Platinum V.EU (PL) and standard nonflattened CC Premium V.EU (CC) rotaries were tested. For cyclic fatigue tests, all the files were rotated in an artificial root canal with a curvature of 45° and a radius of 6.06 mm at 300 rpm (n = 15 in each group). The number of cycles to failure (NCF) was calculated. For torsional tests, the files were rotated at 2 rpm clockwise until fracture occurred. The maximum torque value at fracture was measured and the toughness and distortion angle were computed. Subsequently, 5 fragments were randomly selected in each experiment, the cross-section and longitudinal direction of the fragments were photographed using a scanning electron microscope. An unpaired t-test was performed at a significance level of 95%. RESULTS There was a statistically significant difference in NCF between CC and PL (P < .05). CC showed higher NCF than PL. There was no statistically significant difference between CC and PL with regards to the parameters related to torsional resistance (distortion angle, ultimate strength, and toughness) (P > .05). CONCLUSION Within the limitations of this study, side flattening of the file did not improve cyclic resistance or torsional resistance of the files. As side flattening may reduce a file's cyclic resistance, such files should be used with caution in clinical practice.
Collapse
Affiliation(s)
- Hee-Yoon Jeong
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, South Korea
| | - Jung-Hong Ha
- Department of Conservative Dentistry, College of Dentistry, Kyungpook National University, Daegu, South Korea
| | - Asgeir Sigurdsson
- Department of Endodontics, New York University College of Dentistry, New York University, New York, New York
| | - Ove A Peters
- School of Dentistry, The University of Queensland, Herston, Queensland, Australia
| | - Hyeon-Cheol Kim
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, South Korea
| | - Sang Won Kwak
- Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Dental and Life Science Institute, Pusan National University, Yangsan, South Korea.
| |
Collapse
|
2
|
De Pedro-Muñoz A, Rico-Romano C, Sánchez-Llobet P, Montiel-Company JM, Mena-Álvarez J. Cyclic Fatigue Resistance of Rotary versus Reciprocating Endodontic Files: A Systematic Review and Meta-Analysis. J Clin Med 2024; 13:882. [PMID: 38337577 PMCID: PMC10856014 DOI: 10.3390/jcm13030882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 01/30/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
(1) Background: The failure of nickel-titanium (NiTi) rotary files is a complication related to endodontic instruments. The aim of this study was to compare the resistance to cyclic fatigue between rotary and reciprocating file systems. (2) Methods: Specific PICO: Population (P): artificial root canals; Interventions (I): instrumentation with NiTi rotary and reciprocating files; Comparison (C): rotary versus reciprocating files; Outcome (O): cyclic fatigue resistance. Studies were identified through bibliographic research using electronic databases (Medline, Embase, Scopus, SciELO, and WOS). The studies were combined using a random effects model by the inverse variance method. The effect size was the mean of the time to fracture (TTF) and number of cycles to fracture (NCF). Heterogeneity was assessed using the p value of the Q test for heterogeneity and the I2. (3) Results: TTF for rotary files was determined in 474.5 s and 839.1 for reciprocating without statistically significant differences. NCF for rotary systems was determined in 1444.2 and for reciprocating file systems in 4155.9 with statistically significant differences (p = 0.035), making reciprocating files more resistant. (4) Conclusions: Reciprocating files have better resistance to cyclic fatigue than rotary files. When tested in double curvature canals, reciprocating files also showed higher resistance.
Collapse
Affiliation(s)
- Ana De Pedro-Muñoz
- Department of Endodontics, Faculty of Dentistry, Alfonso X El Sabio University, 28691 Madrid, Spain; (A.D.P.-M.); (C.R.-R.); (P.S.-L.)
| | - Cristina Rico-Romano
- Department of Endodontics, Faculty of Dentistry, Alfonso X El Sabio University, 28691 Madrid, Spain; (A.D.P.-M.); (C.R.-R.); (P.S.-L.)
| | - Patricia Sánchez-Llobet
- Department of Endodontics, Faculty of Dentistry, Alfonso X El Sabio University, 28691 Madrid, Spain; (A.D.P.-M.); (C.R.-R.); (P.S.-L.)
| | - José María Montiel-Company
- Department of Stomatology, Faculty of Medicine and Dentistry, University of Valencia, 46010 Valencia, Spain;
| | - Jesús Mena-Álvarez
- Department of Endodontics, Faculty of Dentistry, Alfonso X El Sabio University, 28691 Madrid, Spain; (A.D.P.-M.); (C.R.-R.); (P.S.-L.)
| |
Collapse
|
3
|
Hu X, Zhao G, Du J, Ye N. Mechanical properties analysis of medical endodontic instruments based on parameterization. J Mech Behav Biomed Mater 2022; 134:105416. [PMID: 36037707 DOI: 10.1016/j.jmbbm.2022.105416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/06/2022] [Accepted: 08/08/2022] [Indexed: 11/19/2022]
Abstract
To study the relationship between structural parameters and mechanical properties of endodontic instruments, the T02004B25 nickel-titanium endodontic instrument was selected for bending and torsion tests and finite element simulation analysis, which demonstrated the feasibility of simulation analysis method. Then based on the idea of parametric design, the models of the endodontic instruments with different structural parameters (cross-section, pitch, taper) were established, and the bending-torsion performance simulation analysis was completed. The results showed that the mechanical properties of endodontic instruments with different structural parameters are different. It is necessary to find the optimal parameters for different structure parameters of endodontic instruments to maximize their service life.
Collapse
Affiliation(s)
- Xiulin Hu
- Key Laboratory of Advanced Design and Simulation Technology for Special Equipment Ministry of Education, Hunan University, Changsha, 410082, China.
| | - Gongwei Zhao
- Key Laboratory of Advanced Design and Simulation Technology for Special Equipment Ministry of Education, Hunan University, Changsha, 410082, China.
| | - Jiachen Du
- Key Laboratory of Advanced Design and Simulation Technology for Special Equipment Ministry of Education, Hunan University, Changsha, 410082, China.
| | - Nanhai Ye
- Key Laboratory of Advanced Design and Simulation Technology for Special Equipment Ministry of Education, Hunan University, Changsha, 410082, China.
| |
Collapse
|
4
|
Special Issue “The State of the Art in Endodontics” Part II. J Clin Med 2022; 11:jcm11154511. [PMID: 35956126 PMCID: PMC9369801 DOI: 10.3390/jcm11154511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 07/30/2022] [Indexed: 11/17/2022] Open
|
5
|
Nair VS, Nachimuthu R. The role of NiTi shape memory alloys in quality of life improvement through medical advancements: A comprehensive review. Proc Inst Mech Eng H 2022; 236:923-950. [PMID: 35486134 DOI: 10.1177/09544119221093460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The significance of advanced smart materials in recent technological research and advancement is apparent from its extensive use in present day devices and instruments. Of the various smart materials in use today, the fascinating category of shape memory alloys (SMAs) is equipped with the ability to return to a previously memorized shape under certain thermomechanical or magnetic stimuli. The unique property of shape memory effect and superelasticity displayed by these materials along with good biocompatibility and corrosion resistance make them ideal for biomedical applications. The various applications of SMAs in surgical instruments, surgical implants, and assistive and rehabilitative devices have significant effect on the day to day life of people in the present age. Majority of these biomedical devices belong to the orthodontic, orthopedic, or surgical fields. Other remarkable applications of SMAs such as in the production of prostheses and orthoses designed through the biomimetic approach are also highly influential in improving the quality of life. The present paper provides an overview of the various properties of shape memory alloys and their applications in the biomedical field over the years, that have had a significant impact on the realm of medical science.
Collapse
Affiliation(s)
- Viswajith S Nair
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| | - Radhika Nachimuthu
- Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, India
| |
Collapse
|
6
|
Wear Analysis of Four Different Single-File Reciprocating Instruments before and after Four Uses in Simulated Root Canals. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12126253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The aim of this study is to assess the surface alterations of four reciprocating instruments before and after the shaping of four resin-simulated root canals. The following four different reciprocating instruments are selected: 10 Reciproc Blue (RB25), 10 WaveOne Gold (WOG), 10 EdgeOne Fire (EOF) and 10 recently introduced instruments OneRECI (OR), for a total of 40 new instruments. Before root canal shaping, each instrument is mounted on a stub in a standardized position and observed using a scanning electron microscope (SEM) to detect any surface alteration, such as microfractures, metal defects, deformations, blunt and disruption of cutting edges, debris, pitting and tip flattening. Micrographs are acquired at the level of the tip, 4 mm, 8 mm and 12 mm from it. After that, each instrument is used in four simulated resin root canals. SEM observation was repeated after the simulated clinical use to assess the wear resistance of the instruments. Surface alterations are registered before and after instrumentation and statistical analysis is performed using a Chi-Square test to verify homogeneity of defects distribution and GLM to evaluate the differences of RMS at baseline and after use for both groups (α level 0.05). Before simulated clinical uses, no alterations are found except for three cases of EOF with metal strips in correspondence to the tip, disruption of the cutting edge of WOG and oily spotting on two different OR. After simulated clinical use, EOF shows a statistically significant difference in terms of spiral distortion and flattening of the cutting edges. The OR shows the highest presence of debris despite the ultrasonic cleaning procedures. No instrument fractures are observed. EOF should be discarded after four clinical uses and carefully inspected after each insertion into root canals. Moreover, tough attention should be paid during disinfection and cleaning procedures after instrumentation considering the copious debris detected in each instrument, particularly in OR.
Collapse
|
7
|
Three-Dimensional Evaluation of the Root Apex of Permanent Maxillary Premolars: A Multicentric Study. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12126159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Aim: Modern endodontics has advanced radically in the recent years, and recently, it has been focused on the concept of mini-invasive treatments. This study aimed to evaluate the sections of the root apices at 1 mm from the radiographic apex using a high-resolution CBCT. Materials and Methods: The current study was performed in three different dental centers. One hundred maxillary permanent premolars (50 first and 50 s premolars) were analyzed using measurement software of the CBCT radiographic pictures. The mesio-distal (M-D) and bucco–palatal (B-P) sections were measured at 1 mm from the radiographic apex of each root. The section of 0.3 mm or less, 1 mm from the anatomical apex of the upper premolars, was decided as the limit value. All values were statistically analyzed. Results: The mean value in the 304 sections analyzed was 1.03 (±0.37). Only 19 sections (6.3%) had measurements less than or equal to 0.3 mm. All these 19 sections were from first premolars (p = 0.002). Conclusions: Based on the data obtained, the authors recommend performing conservative shaping when endodontically treating first maxillary premolars, especially when a pre-operative CBCT to evaluate the actual apical dimensions cannot be acquired.
Collapse
|
8
|
Seracchiani M, Reda R, Zanza A, D'Angelo M, Russo P, Luca T. Mechanical performance and Metallurgical Characteristic of Five Different Single-File Reciprocating Instruments: a Comparative in Vitro and Laboratory Study. J Endod 2022; 48:1073-1080. [PMID: 35667568 DOI: 10.1016/j.joen.2022.05.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/16/2022] [Accepted: 05/26/2022] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Since there are no data regarding an instrument recently introduced on the market (OneRECI), the aim of the study was to assess its mechanical and metallurgical properties comparing them with those of widespread reciprocating instruments such as Reciproc, Reciproc Blue, EdgeOne Fire and WaveOne Gold. METHODS A total of 65 NiTi files from five different reciprocating systems (OneRECI, Reciproc, Reciproc Blue, EdgeOne Fire and WaveOne Gold) were evaluated throughout a combined mechanical and metallurgical method. Mechanical performances of the selected file were examined subjecting each specimen to cyclic fatigue, torsional and bending resistance tests, whilst their metallurgical properties were assessed analyzing the nickel-titanium alloy composition and the phase transformation temperatures respectively through an energy-dispersive X-ray spectroscopy (EDX) and a differential scanning calorimetry (DSC). One-way ANOVA and post hoc Tukey's was performed with significance level set to a 95% confidence level. RESULTS The EDX showed a similar alloy composition for all of the tested files, with nickel percentage of about 52-53% and a corresponding percentage of titanium of 47-48%, whilst the DSC analysis, although evidenced martensitic characteristics for all files, showed differences in terms of phase transformation temperatures. Overall, OneRECI showed the best mechanical performances in terms of cyclic fatigue and torsional resistance (respectively of 32.95 ± 2.33 s and 0.76 ± 0.03 Ncm) and flexibility (48.4 ± 4.1 g), with statistically significant differences for all tests (p<0.05). Reciproc files showed the worst flexibility and cyclic fatigue resistance, respectively of 157.2 ± 8.3 g and 9.27 ± 1.18 s, whilst the EdgeOne Fire showed the lowest torsional resistance (0.39 ± 0.12 Ncm), whit statistically significant differences (p<0.05). CONCLUSIONS Within the limitation of this study, the recently introduced file OneRECI showed the best mechanical performance in comparison to the tested instruments, with an equiatomic composition of the NiTi alloy and a martensitic behavior.
Collapse
Affiliation(s)
- Marco Seracchiani
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy
| | - Rodolfo Reda
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy
| | - Alessio Zanza
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy.
| | - Maurilio D'Angelo
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy
| | - Paola Russo
- Department of Chemical Engineering, Materials, Environment Dipartimento di Ingegneria Chimica Materiali Ambiente, La Sapienza University of Rome, Rome, Italy
| | - Testarelli Luca
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy
| |
Collapse
|
9
|
Mechanical and Metallurgical Evaluation of 3 Different Nickel-Titanium Rotary Instruments: An In Vitro and In Laboratory Study. Bioengineering (Basel) 2022; 9:bioengineering9050221. [PMID: 35621499 PMCID: PMC9137481 DOI: 10.3390/bioengineering9050221] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/11/2022] [Accepted: 05/18/2022] [Indexed: 11/17/2022] Open
Abstract
An in-depth evaluation of the mechanical and metallurgical properties of NiTi instruments is fundamental to assess their performance and to compare recently introduced instrument with widespread ones. According to this, since there are no data on this topic, the aim of the study was to mechanically and metallurgically evaluate an instrument recently introduced into the market (ZenFlex (ZF)), by comparing it with two well-known instruments with similar characteristics: Vortex Blue (VB) and EdgeSequel Sapphire (EES). According to this, 195 instruments were selected: 65 ZF, 65 VB and 65 EES. Each group was divided in subgroups according to the mechanical tests (i.e., cyclic fatigue resistance, torsional resistance and bending ability; (n = 20)) and the metallurgical test (differential scanning calorimetry (n = 5)). A scanning electron microscopy was performed to verify the causes of fracture after mechanical tests (cyclic fatigue and torsional tests). According to results, VB showed the highest flexibility and cyclic fatigue resistance in comparison to the other instruments, with a statistically significant difference (p < 0.05). Regarding torsional resistance, EES showed the lowest value of torque at fracture, with a statistically significant difference, whilst the comparison between ZF and VB showed no statistically significant difference (p > 0.05). DSC analysis pointed out that VB had the highest austenite start and finish temperatures, followed by ESS and then ZF. ESS sample showed the highest martensite start and finish temperatures followed by VB and ZF. Considering the results, it can be concluded that VB showed the best mechanical performance during static tests in comparison to ESS and ZF. This is fundamentally due to the interaction of parameters such as instrument design and heat-treatments that are able to enhance its mechanical performance.
Collapse
|
10
|
Basturk FB, Özyürek T, Uslu G, Gündoğar M. Mechanical Properties of the New Generation RACE EVO and R-Motion Nickel-Titanium Instruments. MATERIALS 2022; 15:ma15093330. [PMID: 35591664 PMCID: PMC9105925 DOI: 10.3390/ma15093330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/21/2022] [Accepted: 05/03/2022] [Indexed: 12/04/2022]
Abstract
This study aimed to evaluate and compare the dynamic cyclic fatigue, torsional and bending resistance of two novel RACE EVO (FKG Dentaire SA, La Chaux de Fonds, Switzerland) and R-Motion (FKG) nickel−titanium instruments with traditional RaCe (FKG) instruments. RACE EVO, R-Motion and RaCe instruments with a size of 25 and taper of 0.06 were used. A dynamic cyclic fatigue test was used to assess the time to fracture. The fractured surfaces were further analyzed using scanning electron microscopy at ×350 and ×3000 magnifications. A torsional resistance test was performed to measure the maximum torsional strength and angle of rotation. Phase transformations with temperature were evaluated using differential scanning calorimetry. The results were statistically analyzed with a Kruskal−Wallis test at a 5% significance level. R-Motion had the highest time to fracture and the lowest torsional and bending resistance, whereas RaCe had the lowest time to fracture and the highest torsional and bending resistance (p < 0.05). In relation to the angle of rotation, RACE EVO instruments had the highest deformation capacity followed by R-Motion and RaCe instruments (p < 0.05). The greater cyclic fatigue resistance and lower torsional and bending resistance results indicate that the novel R-Motion and RACE EVO instruments are less rigid and more flexible than RaCe instruments.
Collapse
Affiliation(s)
- Fatima Betul Basturk
- Department of Endodontics, Istanbul Gelişim University, Istanbul 34310, Turkey
- Correspondence:
| | - Taha Özyürek
- Department of Endodontics, Bahçeşehir University, Istanbul 34734, Turkey;
| | - Gülşah Uslu
- Department of Endodontics, Çanakkale Onsekiz Mart University, Çanakkale 17100, Turkey;
| | - Mustafa Gündoğar
- Department of Endodontics, Istanbul Medipol University, Istanbul 34083, Turkey;
| |
Collapse
|
11
|
Zanza A, Russo P, Di Matteo P, Reda R, Di Nardo D, Gambarini G, Testarelli L. Mechanical properties and metallurgical features of two similar endodontic rotary instruments with different heat treatments (FireWire™ and Gold). Sci Prog 2022; 105:368504221103763. [PMID: 35656775 PMCID: PMC10364944 DOI: 10.1177/00368504221103763] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to explain the mechanical differences between EdgeTaper Platinum (ETP) and ProTaper Gold (PTG) determining the transition temperatures and the composition of the alloy of ETP, since no data are present in literature. A total of 130 instruments were selected: 65 ETP F2 and 65 PTG F2. 20 instruments per type were submitted to each mechanical tests. The cyclic fatigue and torsional tests were performed at a pre-set temperature of 35 °C ± 1 °C. During the cyclic fatigue test, Time to fracture, number of cycles to fracture (NCF) and the fragment length (FL) were recorded. During the static torsional, Torque to Fracture (TtF) and FL were recorded. The fracture surface of 5 randomly selected fragments from each test was examined through a Scanning Electron Microscopy (SEM) and an EDX analysis was performed. 20 instruments per type were submitted to a bending test The force generated (grams) to bend each was recorded. Recorded data of mechanical and metallurgical tests were statistically analyzed using a one-way analysis of variance (ANOVA) test with significance set to a 95% confidence level. ETP F2 showed a higher cyclic fatigue resistance and bending ability than PTG F2, with a statistically significant difference (p < 0.05). PTG showed a higher torsional resistance with a statistically significant difference (p < 0.05). DSC analysis of 5 samples for each instrument type pointed out that the austenite finish temperature of PTG was higher than the ETP, respectively of 49.99 ± 3.31 (°C) and 38.92 ± 1.75 (°C). EDX analysis confirmed the near-equiatomic composition of the Ni-Ti alloys, with a presence of a third component recognized as rubidium in the ETP samples. ETP showed higher flexibility in comparison with PTG, despite the latter is characterized by a more martensitic characterization. since its Af temperature is higher than the ETP.
Collapse
Affiliation(s)
- Alessio Zanza
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, via Caserta 6, 00161 Rome, Italy
| | - Paola Russo
- Department of Chemical Engineering, Materials, Environment DICMA, La Sapienza University of Rome, via Scarpa, 00161 Rome, Italy
| | - Paola Di Matteo
- Department of Chemical Engineering, Materials, Environment DICMA, La Sapienza University of Rome, via Scarpa, 00161 Rome, Italy
| | - Rodolfo Reda
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, via Caserta 6, 00161 Rome, Italy
| | - Dario Di Nardo
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, via Caserta 6, 00161 Rome, Italy
| | - Gianluca Gambarini
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, via Caserta 6, 00161 Rome, Italy
| | - Luca Testarelli
- Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, via Caserta 6, 00161 Rome, Italy
| |
Collapse
|
12
|
Quantitative Evaluation of Apically Extruded Debris of Root Canal Dentin Layer with WaveOne, ProTaper Next, ProTaper Gold Rotary File Systems. COATINGS 2022. [DOI: 10.3390/coatings12040451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Endodontic flare-up or post-operative pain occurs when debris such as necrotic pulp tissue, dentin chips, irrigants, and microorganisms are extruded from the apical foramen intraoperatively into the periradicular tissue during root canal instrumentation. This study compared the amount of apical debris extrusion of the root canal dentin layer after using reciprocating and rotary file systems (WaveOne, ProTaper Next and ProTaper Gold). Sixty extracted human maxillary central incisors with one canal and closed apex were included in the study. Samples were randomly and equally divided into three groups (n = 20) according to the file systems used for preparation of the root canal. Teeth in the WO group were instrumented by WaveOne, while the PTN group were instrumented by ProTaper Next, and teeth samples in the PTG group were cleaned and shaped by ProTaper Gold. The mean apically extruded debris weight in grams was estimated using the modified Myers and Montgomery experimental model. Analysis of variance (ANOVA) test was used for the comparison of debris weight in three groups. Post hoc LSD test was applied for pairwise comparison of debris weight. The α value of significance was 0.05. The WO group had significantly lower mean debris weight than the PTN and PTG groups (p = 0.001). Post hoc pairwise comparison revealed that there was a statistically significant difference in mean debris weight between the WO group and PTN group (0.0215 vs. 0.0341, p = 0.001); and the WO group and PTG group (0.0215 vs. 0.0324, p = 0.003). Root canal preparations with different file systems were associated with apical extrusion of the debris from the root canal dentin layer. However, the WaveOne system resulted in a comparatively lower amount of apical debris layer extrusion than the ProTaper Next and ProTaper Gold rotary file systems.
Collapse
|
13
|
Thakur VS, Kankar PK, Parey A, Jain A, Kumar Jain P. Numerical analysis of WaveOne Gold and 2Shape endodontic files during root canal treatment. Proc Inst Mech Eng H 2022; 236:329-340. [DOI: 10.1177/09544119211068950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study aims to develop and analyse a finite element model of the endodontic nickel-titanium (NiTi) instrument during the root canal treatment (RCT). The 3D model of the tooth and the endodontic instrument has been created using computer-aided design software. The nonlinear explicit dynamic analysis in the CAE package (ANSYS) has been used to analyse the mechanical behaviour of endodontic instruments such as total deformation, equivalent elastic strain, and equivalent stress during canal preparation. The mechanical behaviour of three commercially available endodontic NiTi alloy instruments such as WaveOne Gold (WOG), 2Shape 1 (TS1) and 2Shape 2 (TS2) endodontic files was evaluated using FEA. Consequently, the effect of deformation, equivalent stress and equivalent elastic strain on endodontic files during cleaning and shaping are investigated and compared. The results show that the total deformation and equivalent elastic strain are maximum in the TS1 endodontic file in comparison to TS2 and WOG files.
Collapse
Affiliation(s)
- Vinod Singh Thakur
- Department of Mechanical Engineering, Indian Institute of Technology Indore, Indore, Madhya Pradesh, India
| | - Pavan Kumar Kankar
- Department of Mechanical Engineering, Indian Institute of Technology Indore, Indore, Madhya Pradesh, India
| | - Anand Parey
- Department of Mechanical Engineering, Indian Institute of Technology Indore, Indore, Madhya Pradesh, India
| | - Arpit Jain
- Department of Oral Medicine and Radiology, College of Dental Science and Hospital, Rau, Indore, Madhya Pradesh, India
| | - Prashant Kumar Jain
- PDPM Indian Institute of Information Technology, Design and Manufacturing, Jabalpur, Madhya Pradesh, India
| |
Collapse
|
14
|
Nickel–Titanium Rotary Instruments: Mechanical and Metallurgical Characteristics. Clin Pract 2022; 12:94-96. [PMID: 35200263 PMCID: PMC8870687 DOI: 10.3390/clinpract12010012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 02/10/2022] [Indexed: 02/04/2023] Open
|
15
|
Mohamed RH, Abdelrahman AM, Sharaf AA. Evaluation of rotary file system (Kedo-S-Square) in root canal preparation of primary anterior teeth using cone beam computed tomography (CBCT)-in vitro study. BMC Oral Health 2022; 22:13. [PMID: 35042489 PMCID: PMC8764846 DOI: 10.1186/s12903-021-02021-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 12/13/2021] [Indexed: 11/12/2022] Open
Abstract
Background In recent years, pediatric endodontics has witnessed various advances including use of rotary files in pulpectomy. This study aimed to comparatively evaluate taper, amount of dentin removal and instrumentation time of the pediatric rotary Kedo-S Square file,
hand K-files and H-files in primary canines using cone beam computed tomography (CBCT). Methods 60 primary canines were randomly assigned into three groups; A1 Kedo-S-Square rotary file (group I), hand stainless steel K file (group II) and hand stainless steel H file (group III). Teeth were mounted in vinyl poly siloxane impression material templates to be scanned before and after instrumentation by CBCT scans using Ondemand 3D software. Shaping ability of the files were evaluated in terms of taper of the canal and amount of dentin remaining of each group. Instrumentation time was recorded using a digital stopwatch. Results Kedo-S Square removed a significantly less amount of dentin in both apical (P < 0.002) and coronal thirds (P < 0.014). Taper of the preparations showed significant differences as Kedo-S Square file showed good taper in maximum number of root canals, while maual K- and H-files showed poor taper in maximum number of root canals (P < 0.0001). Rotary Kedo-S Square files required less instrumentation time (P < 0.0001). Conclusion The use of rotary Kedo-S Square files resulted in better conservation of tooth structure, superior tapering ability and least instrumentation time compared to hand K- and H-files.
Collapse
|
16
|
Metallurgical Tests in Endodontics: A Narrative Review. Bioengineering (Basel) 2022; 9:bioengineering9010030. [PMID: 35049739 PMCID: PMC8773015 DOI: 10.3390/bioengineering9010030] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 11/17/2022] Open
Abstract
Since there are no reviews of the literature on this theme, the aim of this narrative review is to summarize the metallurgical tests used in endodontics, pointing out their functional use and their pros and cons and giving readers a user-friendly guide to serve as an orientation aid in the plethora of metallurgical tests. With this purpose, a literature search for articles published between January 2001 and December 2021 was conducted, using the electronic database PubMed to collect all published articles regarding the metallurgical tests used in endodontics for the evaluation of NiTi rotary instruments. The search was conducted using the following keywords: “metallurgy”, “differential scanning calorimetry” (DSC), “X-ray diffraction” (XRD), “atomic force microscopy” (AFM), “energy-dispersive X-ray spectroscopy” (EDS), “focused ion beam analysis” (FIB) and “Auger electron spectroscopy” (AES) combined with the term “endodontics” or “NiTi rotary instruments”. Considering the inclusion and exclusion criteria, of the 248 articles found, only 81 were included in the narrative review. According to the results, more than 50% of the selected articles were published in one of the two most relevant journals in endodontics: International Endodontic Journal (22.2%) and Journal of Endodontics (29.6%). The most popular metallurgical test was DSC, with 43 related articles, followed by EDS (33 articles), AFM (22 articles) and XRD (21 articles). Few studies were conducted using other tests such as FIB (2 articles), micro-Raman spectroscopy (4 articles), metallographic analysis (7 articles) and Auger electron spectroscopy (2 articles).
Collapse
|
17
|
Bhat R, Kini A, Shetty P, Kansara P, Penugonda B. Cyclic Fatigue Resistance and Surface Roughness of Rotary NiTi Instruments after Simulated Clinical Use in Curved Root Canals – An Atomic Force Microscopy Study. PESQUISA BRASILEIRA EM ODONTOPEDIATRIA E CLÍNICA INTEGRADA 2022. [DOI: 10.1590/pboci.2022.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
| | - Arjun Kini
- New York University College of Dentistry, USA
| | | | | | | |
Collapse
|
18
|
Zanza A, D’Angelo M, Reda R, Gambarini G, Testarelli L, Di Nardo D. An Update on Nickel-Titanium Rotary Instruments in Endodontics: Mechanical Characteristics, Testing and Future Perspective-An Overview. Bioengineering (Basel) 2021; 8:bioengineering8120218. [PMID: 34940371 PMCID: PMC8698980 DOI: 10.3390/bioengineering8120218] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 12/21/2022] Open
Abstract
Since the introduction of Nickel-Titanium alloy as the material of choice for the manufacturing of endodontic rotary instruments, the success rate of the root canal therapies has been significantly increased. This success mainly arises from the properties of the Nickel-Titanium alloy: the biocompatibility, the superelasticity and the shape memory effect. Those characteristics have led to a reduction in time of endodontic treatments, a simplification of instrumentation procedures and an increase of predictability and effectiveness of endodontic treatments. Nevertheless, the intracanal separation of Nickel-Titanium rotary instruments is still a major concern of endodontists, with a consequent possible reduction in the outcome rate. As thoroughly demonstrated, the two main causes of intracanal separation of endodontic instruments are the cyclic fatigue and the torsional loads. As results, in order to reduce the percentage of intracanal separation research and manufacturers have been focused on the parameters that directly or indirectly influence mechanical properties of endodontic rotary instruments. This review describes the current state of the art regarding the Nickel-Titanium alloy in endodontics, the mechanical behavior of endodontic rotary instruments and the relative stresses acting on them during intracanal instrumentation, highlighting the limitation of the current literature.
Collapse
|
19
|
Evaluation of Curved Canal Transportation Using the Neoniti Rotary System with Reciprocal Motion: A Comparative Study. Int J Dent 2021; 2021:4877619. [PMID: 34868317 PMCID: PMC8635869 DOI: 10.1155/2021/4877619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/23/2021] [Accepted: 11/02/2021] [Indexed: 11/17/2022] Open
Abstract
The ideal root canal preparation is where the original canal morphology is maintained during the biomechanical preparation. Preparation of curved canals has always been a challenge to clinicians. Better results have been suggested for a single NiTi instrument with reciprocating motion than the conventional continuous rotation method in the preparation of curved root canals. Although the Neoniti rotary system is not suggested to be used with reciprocal motion, running a pilot study, we found that it could be possible. The present study aimed to investigate if shaping curved canals using the Neoniti rotary system with reciprocal motion leads to better results in terms of root canal transportation. One hundred acrylic j-shape canal simulator endoblocks were used in this study. Five preparation sequences were applied: GPS followed by A1#20 (GPS + A1#20), GPS followed by A1#20 and then A1#25 (GPS + A1#20 + A1#25), GPS followed by A1#25 (GPS + A1#25), hand file followed by A1#20 (hand file + A1#20), and GPS followed by A1#20 (with reciprocal motion) (GPS + A1#20(reciprocal)). Pictures were taken from blocks once before and once after preparation from two dimensions. Before-and-after pictures were superimposed in Photoshop software. Measurements were performed in Digimizer. The number of autoreverses and pecking motions was recorded after reviewing the recorded videos. Data were analyzed in SPSS, version 26. A p value of less than 0.05 was considered statistically significant. The group GPS + A1#20 + A1#25 had more transportation compared with the others, at apical, middle, and coronal thirds not only in the frontal view but also in the lateral view. Other groups were not significantly different. The number of peckings and autoreverses was significantly less when A1#25 was used after GPS and A1#20. When A1#20 was used with reciprocal motion, it had less peckings compared with the same file with continuous rotation, and no autoreverses were observed in that group. Using Neoniti files with reciprocal motion might result in less instrument fatigue and favorable results, with respect to canal anatomy preservation. Using A1#20 before A1#25 also will decrease the stress on the instrument during preparation. However, this may lead to significantly more canal transportation.
Collapse
|
20
|
Schäfer E, Bürklein S, Donnermeyer D. A critical analysis of research methods and experimental models to study the physical properties of NiTi instruments and their fracture characteristics. Int Endod J 2021; 55 Suppl 1:72-94. [PMID: 34862796 DOI: 10.1111/iej.13673] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 12/03/2021] [Indexed: 11/27/2022]
Abstract
The aim of this review is to provide a critical overview of the physical properties (surface hardness, cutting efficiency, bending properties, flexibility and cyclic fatigue resistance) of NiTi instruments. Frequently used experimental models regarding these aspects will be presented and discussed with regard to their strengths and weaknesses. For all these aspects, a plethora of experimental models have been described. Based on a critical appraisal and especially taking the appropriate translation of experimental findings to clinical endodontics into account, suggestions for future research based on clearly defined and valid experimental methodologies will be provided. Up to now, very few attempts have been made to assess which particular physical properties of NiTi instruments exert an impact on the clinical outcome of root canal treatment. Departure from merely focusing on physical properties and fracture characteristics towards more biological aspects in terms of treatment outcome is essential.
Collapse
Affiliation(s)
- Edgar Schäfer
- Central Interdisciplinary Ambulance in the School of Dentistry, Münster, Germany
| | - Sebastian Bürklein
- Central Interdisciplinary Ambulance in the School of Dentistry, Münster, Germany
| | - David Donnermeyer
- Department of Periodontology and Operative Dentistry, Westphalian Wilhelms-University, Münster, Germany
| |
Collapse
|
21
|
Effect of Passive Ultrasonic Irrigation over Organic Tissue of Simulated Internal Root Resorption. Int J Dent 2021; 2021:3130813. [PMID: 34745262 PMCID: PMC8570868 DOI: 10.1155/2021/3130813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/13/2021] [Accepted: 10/15/2021] [Indexed: 01/17/2023] Open
Abstract
This study aimed to evaluate the efficacy of passive ultrasonic irrigation (PUI) on dissolving the organic tissue inside simulated internal root resorption (IRR) using sodium hypochlorite (NaOCl) or chlorhexidine (CHX). A total of 40 human lower premolars were collected based on dimensional and morphological similarities. The roots were embedded in cylinders (3 cm diameter; 2.5 cm height) of self-cured acrylic resin, and then an IRR was simulated. The specimens were divided into 4 groups (n = 10) according to irrigation protocols: group 1: CHX + PUI; group 2: CHX; group 3: NaOCl + PUI; group 4: NaOCl. The total irrigation time was 150 s at a flow rate of 5 mL/min. A tissue mass of porcine palatine mucosa was used to simulate the organic tissue, it was weighed before and after the irrigation using an analytic balance, and the difference between both readings was calculated and transferred to percentage values. Data were submitted to statistical analysis using two-way ANOVA (factors: irrigant type and with/without PUI) and Tukey's test for multiple comparisons among the experimental groups (α = 0.05). There was a significant difference in both factors (irrigant: p=0.04; PUI: p ≤ 0.001). The groups that used PUI were more effective in dissolving the organic tissue of the IRR simulation than the groups without PUI. PUI is more effective than the syringe and needle irrigation in organic tissue dissolution.
Collapse
|
22
|
Role of the Crystallographic Phase of NiTi Rotary Instruments in Determining Their Torsional Resistance during Different Bending Conditions. MATERIALS 2021; 14:ma14216324. [PMID: 34771850 PMCID: PMC8585440 DOI: 10.3390/ma14216324] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 11/16/2022]
Abstract
The aim of this study was to assess the role of the crystallographic phase of Nickel-titanium (NiTi) rotary instruments in determining their torsional resistance during different bending conditions, such as different degrees and angles of curvature. 200 F-One 20.04 instruments (Fanta Dental, Shanghai, China) were used, 100 austenitic instruments and 100 martensitic instruments. Each group was divided in 5 subgroups according to the different bending conditions (straight canal, 90° or 60° of curvature degrees and 3 mm or 5 mm of radius of curvature). The static torsional test was performed by using a device composed of an electric motor capable of recording torque values (N·cm); a vice used to secure the instruments at 3 mm from the tip; and artificial canals, which allow instruments to remain flexed during test. Each instrument was rotated at 500 rpm with a torque limit set to 5.5 Ncm until its fracture. Torque at Fracture (TtF) was registered. A scanning electron microscopy (SEM) observation was conducted. The collected data confirm that an increase in the angle of curvature and a decrease in the radius of curvature of the artificial canals lead to an increase of TtF values with a statistically significant difference (p < 0.05), both in the austenitic and martensitic groups. Regarding the comparison between austenitic and martensitic groups in the same bending condition, a statistically significant difference was found only when the torsional test was performed in the canals with the degrees of curvature of 90° and the radius of curvature of 3 mm and 5 mm, with the austenitic instruments showing a higher TtF than the martensitic ones. In conclusion, it can be stated that the crystallographic phase influences the maximum torque at fracture when the instruments are subjected to severe bending and that the radius of curvature significantly influences their torsional resistance.
Collapse
|
23
|
Van Pham K. Differential scanning calorimetric investigations of three rotary nickel-titanium instrument systems before and after simulated clinical uses. BMC Oral Health 2021; 21:488. [PMID: 34600503 PMCID: PMC8487136 DOI: 10.1186/s12903-021-01857-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The transformation temperatures were important values, influencing the mechanical properties and clinical performance of nickel-titanium instruments. The aim of this study was to determine the transformation temperatures of three rotary nickel-titanium (NiTi) instruments: Reciproc, HyFlex CM Pro, and Neoniti before and after simulated clinical uses. METHODS Ninety new NiTi instruments of three single-file instruments: Reciproc, HyFlex CM Pro, and Neoniti were divided into three groups. Thirty instruments of each group were divided into 3 subgroups (10 instruments for each subgroup): new, one-time simulated clinical used and sterilised, and three times simulated clinical used and sterilized subgroups. The instruments were in the as-received condition for the new subgroups, one time used in the plastic endo-training blocks and sterilised for the one-time subgroups, and three times used in the plastic endo-training blocks and sterilised for the three times subgroups. Each instrument in subgroups was cut into four small segments of 4-5 mm. All segments of instruments were analysed using Differential Scanning Calorimetry (DSC). Data was collected and analysed using SPSS version 20.0 with ANOVA test or Kruskal-Wallis test at the significant level of 0.05. RESULTS There was not significant difference between before and after simulated clinical use with sterilised procedure in three NiTi instrument systems. The austenite-finish (Af) temperatures of three instrument systems were higher than that of the human body (37 °C), of these, the Af temperature of Neoniti was highest and that of HyFlex CM Pro was lowest. CONCLUSIONS The austenite-finish (Af) temperatures of three NiTi instruments were higher than that of human body temperature, therefore, material was in the phase transformation from martensite to austenite, gives the instruments more flexibility when used in the clinical situation.
Collapse
Affiliation(s)
- Khoa Van Pham
- Department of Operative Dentistry and Endodontics, Faculty of Odonto-Stomatology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, 700000, Vietnam.
| |
Collapse
|
24
|
Angle of Insertion and Torsional Resistance of Nickel-Titanium Rotary Instruments. MATERIALS 2021; 14:ma14133744. [PMID: 34279315 PMCID: PMC8269838 DOI: 10.3390/ma14133744] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 06/25/2021] [Accepted: 06/30/2021] [Indexed: 12/20/2022]
Abstract
Previously published studies have investigated the influence of instrument access on cyclic fatigue resistance. However, no studies have evaluated the relationship between angulated access and torsional resistance. The aim of this study was to investigate the influence of the angle of access on the torsional resistance of endodontic instruments. One hundred and eighty instruments were selected: 90 F-One Blue 25/04 and 90 HeroShaper 25/04 instruments. Three subgroups (n = 30) for each instrument type (A and B) were established according to the angle of insertion of the instruments inside the artificial canal (0°, 10° and 20°). The tests were performed using a custom-made device consisting of the following: a motor that can record torque values of 0.1 s; interchangeable stainless-steel canals with different curvature (0°, 10° and 20°) that allow the instrument’s angulated insertion and keep it flexed during testing procedures; and a vise used to secure the instrument at 3 mm from the tip. Torque limit was set to 5.5 Ncm, and each instrument was rotated at 500 rpm until fracture occurred. Torque to fracture (TtF) was registered by the endodontic motor, and the fragment length (FL) was measured with a digital caliper. Fractographic analysis was performed using a scanning electron microscopy (SEM) evaluation to confirm the cause of failure. TtF values and fragment length (FL) values were statistically analyzed using one-way analysis of variance (ANOVA) test and the Bonferroni correction for multiple comparisons across the groups with significance set to a 95% confidence level. Regarding the F-One Blue instruments, the results showed a higher TtF for group A3 (20°) than for group A1 (0°) and group A2 (10°), with a statistically significant difference between group A3 and the other two groups (p < 0.05), whereas no statistically significant difference was found between group A1 and group A2 (p > 0.05). Regarding the HeroShaper instrument, the results showed the highest TtF for group B3, with a statistically significant difference between the three subgroups B1, B2 and B3 (p < 0.05). The results showed that the torsional resistance increases as the angle of instrument access increases with a varying intensity, according to the crystallographic phase of the instrument selected.
Collapse
|