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Kasuga Y, Kimura S, Maki K, Unno H, Omori S, Hirano K, Ebihara A, Okiji T. Phase transformation and mechanical properties of heat-treated nickel-titanium rotary endodontic instruments at room and body temperatures. BMC Oral Health 2023; 23:825. [PMID: 37904159 PMCID: PMC10614384 DOI: 10.1186/s12903-023-03550-6] [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: 07/04/2023] [Accepted: 10/18/2023] [Indexed: 11/01/2023] Open
Abstract
BACKGROUND The aim of this study was to evaluate the phase composition, phase transformation temperatures, bending property, and cyclic fatigue resistance of different heat-treated nickel-titanium (NiTi) rotary instruments with the same tip diameter and taper at room (RT; 25 ± 1 °C) and body (BT; 37 ± 1 °C) temperatures. METHODS Five heat-treated NiTi rotary instruments, HyFlex EDM (EDM), HyFlex CM (CM), Vortex Blue (VB), RE file CT (RE) and JIZAI, and a non-heat-treated NiTi rotary instrument (Mtwo) with a size 40, 0.04 taper were investigated. Temperature-dependent phase transformation was examined with differential scanning calorimetry (DSC). The bending loads of the instruments at RT and BT were evaluated using a cantilever-bending test. Cyclic fatigue resistance at RT and BT was measured using a dynamic test, during which the instruments were rotated in combination with a 2-mm back-and-forth motion in an artificial curved canal, and the number of cycles to failure (NCF) was determined. The results were analyzed using two-way repeated measures analysis of variance, a simple main effect test, and the Bonferroni test (α = 0.05). RESULTS DSC results indicated that EDM and Mtwo were primarily composed of martensite/R-phase and austenite, respectively, while the other heat-treated instruments were composed of a mix of martensite/R-phase and austenite at the tested temperatures. Regardless of the temperature setting, the bending loads of heat-treated instruments were significantly lower than those of Mtwo (p < 0.05). EDM showed the lowest bending loads and highest NCF at both temperatures (p < 0.05). CM, VB, and JIZAI showed significantly higher bending loads at BT than at RT (p < 0.05). The NCF of all the heat-treated instruments, except VB, was lower at BT than at RT (p < 0.05). At BT, the NCF of CM, VB, RE, and JIZAI were not significantly higher than that of Mtwo (p > 0.05). CONCLUSIONS Heat-treated NiTi instruments exhibited lower bending loads and higher NCF values than Mtwo. However, this tendency was less pronounced at BT than at RT, especially in the NCF values of instruments with a mixture of martensite/R-phase and austenite phases at the tested temperatures.
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Affiliation(s)
- Yuka Kasuga
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Shunsuke Kimura
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
| | - Keiichiro Maki
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Hayate Unno
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Satoshi Omori
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Keiko Hirano
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Arata Ebihara
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Takashi Okiji
- Department of Pulp Biology and Endodontics, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
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Jamleh A, Albanyan H, Alaqla A, Alissa H, Alshetan N, Alraffa S, Alfadley A. Impact of cooling on shaping ability of thermally treated files in canal models with double curvature. PeerJ 2023; 11:e15830. [PMID: 37576504 PMCID: PMC10416767 DOI: 10.7717/peerj.15830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/11/2023] [Indexed: 08/15/2023] Open
Abstract
Background This study compared the ability of thermally treated files in shaping simulated canals with double curvature. Fifty-six canals were enlarged to a final size of 25 with ProTaper Next (PTN) or ZenFlex (ZF). Materials Half of the samples were shaped with cooled files (n = 14 each). The amount of removed resin was measured and canal deviation was determined at eight levels. Shaping time and maximum shaping torque values were also recorded. Data were statistically analyzed using analysis of variance and LSD, Kruskal-Wallis, and chi-square tests at a 0.05 significance level. Results Compared to PTN and cooled PTN, ZF and cooled ZF required lesser time to shape the canals. The maximum torques were found comparable between the groups. All the groups generated negligible deviations at every canal level evaluated and maintained the canal geometry. Although not significant, the cooled PTN and ZF files exhibited lesser canal deviations than their counterparts. Conclusion All groups demonstrated similar shaping ability whilst maintaining the original curvature of the canal in simulated canals with double curvature. However, ZF groups were able to shape the canals faster than PTN groups. There was a trend that cooled files made lesser canal deviations compared to their counterparts.
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Affiliation(s)
- Ahmed Jamleh
- Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Hajar Albanyan
- Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Ali Alaqla
- Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Hamad Alissa
- Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Nawaf Alshetan
- Dr. Sulaiman Al-Habib Medical Group, Riyadh, Saudi Arabia
| | | | - Abdulmohsen Alfadley
- Department of Restorative and Prosthetic Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
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Recent Progress on the Applications of Nanomaterials and Nano-Characterization Techniques in Endodontics: A Review. MATERIALS 2022; 15:ma15155109. [PMID: 35897542 PMCID: PMC9331596 DOI: 10.3390/ma15155109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 02/06/2023]
Abstract
The impact of nano-based technologies in endodontics for the identification and treatment of various dental infections is showing fast progress. Studies show that nanoparticles could serve as useful agents with many beneficial results and continue to be promising in the field of endodontics. To ensure progress and improvements on novel nanomaterials in relation to their physicochemical and biological properties, nano-identification methods for the detection and evaluation of diseases need to be further highlighted. This study aims to review the current technological progress and recent research outcomes as well as possible prospective applications of nano-based technologies in endodontics. A comprehensive literature survey has been carried out on the utilizations of nanomaterials and nano-characterization techniques in endodontics. The current status and recent applications in endodontics are discussed with illustrative examples. The results have shown that the progress and improved accuracy of nano-identification techniques enabled a better characterization, evaluation and selection of appropriate treatment plans for endodontics-related diseases. The results have been inspiring for further clinical investigations. Nano-endodontics is still a developing field with a strong potential for revolutions of novel materials and techniques in the diagnosis and treatment of dental diseases. Further improvements in nanoparticles properties will pave the way for the development of many beneficial endodontic therapeutic agents. The future looks encouraging for sustainable products and testing methods for clinical endodontic applications.
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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.
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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
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Liu H, Li Y, Chai G, Lv Y, Li C, Li S, Yang C, Li A, Wang Y, Li W. Effect of synchronous irrigation on cyclic fatigue of nickel-titanium instrument in the dynamic and static models. J Appl Biomater Funct Mater 2021; 19:2280800020987403. [PMID: 33509031 DOI: 10.1177/2280800020987403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To evaluate the effect of synchronous water irrigation on the fatigue resistance of nickel-titanium instrument. METHODS A standardized cyclic fatigue test models were established, and five types of nickel-titanium instruments (PTU F1, WO, WOG, RE, and M3) were applied. Each instrument was randomly divided into two groups (N = 12). There was synchronous water irrigation in the experimental group, and no water irrigation in the control group. Besides, ProTaper Universal F1 was randomly divided into 10 groups (N = 20). In the static group, nickel-titanium instruments were divided into one control group (no irrigation, N = 20) and six experimental group (irrigation, N = 20) based on different flow rate, angle and position; while in the dynamic group, instruments were divided into one control group (no irrigation, N = 20) and two experimental group (irrigation, N = 20) based on different flow rate. The rotation time (Time to Failure, TtF) of instruments was recorded and analyzed. RESULTS According to the static experiments, the TtF of instruments in all experimental groups was significantly higher than that in the static control group. Besides, the dynamic tests of PTU F1 showed that the TtF in the experimental group was significantly higher than that in the dynamic control group. Compared with control group, the TtF in the experimental groups increased by at least about 30% and up to 160%. The static and dynamic tests of PTU F1 showed that the TtF of nickel-titanium instrument in all experimental groups was significantly higher than that in the control group. However, there was no significant difference between any two experimental groups. CONCLUSION Regardless of dynamic or static model, TtF with irrigation was longer than that with non-irrigation, indicating that synchronous irrigation can increase the fatigue resistance of nickel-titanium instrument. However, different irrigation conditions may have the same effect on the fatigue resistance.
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Affiliation(s)
- Haiyun Liu
- Graduate Training Base, The Fourth Medical Center, Chinese PLA General Hospital, Jinzhou Medical University, Beijing, China.,Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yanfeng Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Guangquan Chai
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yuan Lv
- Department of Stomatology, China Aerospace Science & Industry Corporation 731 Hospital, Beijing, China
| | - Changjian Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Shumao Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Chunhao Yang
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Aishunag Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Yingdi Wang
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Weiwei Li
- Department of Stomatology, The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
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Alqedairi A, Alfawaz H, Abualjadayel B, Alanazi M, Alkhalifah A, Jamleh A. Torsional resistance of three ProTaper rotary systems. BMC Oral Health 2019; 19:124. [PMID: 31226984 PMCID: PMC6588856 DOI: 10.1186/s12903-019-0820-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 06/12/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aim of this study is to compare the torsional resistance of the available ProTaper rotary systems, namely, ProTaper Universal (PTU), ProTaper Next (PTN), and ProTaper Gold (PTG). METHODS A total of 195 files from the three systems distributed into 13 groups (PTU-S1, PTU-S2, PTU-F1, PTU-F2, PTU-F3, PTG-S1, PTG-S2, PTG-F1, PTG-F2, PTG-F3, PTN-X1, PTN-X2 and PTN-X3) were subjected to torsional fatigue until failure. The torsional test was performed according to ISO 3630-1, where each file was placed in a straight position to eliminate the influence of cyclic fatigue. The Kruskal-Wallis test was conducted to compare the mean maximum torques and angular deflections at fracture for the groups, and the Mann-Whitney test was performed for pairwise comparisons. The significance level was set at 0.05 and the fractured surfaces were examined under a scanning electron microscope. RESULT Among the tested files, PTG-S1 had the lowest torsional fatigue resistance, whereas PTU-F2 and PTU-F3 had the highest torsional resistance. The scanning electron microscope showed typical features of torsional failure. CONCLUSION The new ProTaper systems (PTG and PTN) did not show improved torsional resistance in comparison with PTU.
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Affiliation(s)
- Abdullah Alqedairi
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Hussam Alfawaz
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Bader Abualjadayel
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Mohammad Alanazi
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Ahmad Alkhalifah
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Ahmed Jamleh
- King Abdullah International Medical Research Centre, Restorative and Prosthetic Dental Sciences, College of Dentistry, Ministry of National Guard Health Affairs, King Saud bin Abdulaziz University for Health Sciences, P.O. Box 22490, Riyadh, 11426, Saudi Arabia.
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Alfouzan K, Jamleh A. Fracture of nickel titanium rotary instrument during root canal treatment and re-treatment: a 5-year retrospective study. Int Endod J 2017; 51:157-163. [PMID: 28796346 DOI: 10.1111/iej.12826] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 08/06/2017] [Indexed: 11/27/2022]
Abstract
AIM To evaluate retrospectively the incidence of K3 nickel titanium rotary instrument fracture in referred cases during root canal treatment and re-treatment. METHODOLOGY Clinical and radiographic reports of 12 867 endodontic cases treated at the King Abdulaziz medical city between January 2010 and November 2015 were reviewed to obtain information on intracanal fractured instruments with respect to the treatment performed, tooth type and the size and at what level the instrument fractured (coronal, middle or apical). The degree of canal curvature was classified into mild (<10° ), moderate (10-25° ) or severe (>25° ). Logistic regression was used to test the incidence of instrument fracture in relation to the root canal treatment performed and tooth type. Chi-square tests were used to analyse the fracture incidence in the treated teeth in respect to fracture level and fractured file diameter. The level of significance was set at 0.05. RESULTS Root canal treatment was performed on 8946 cases, whilst re-treatment was performed on 3921 cases. The fracture incidence was higher during re-treatment cases (2.96%) than in primary root canal treatment (0.74%) (P < 0.001) with a 1.41% incidence overall. There was a trend for more fractures in maxillary (1.68%) and mandibular (1.35%) molar teeth. Moreover, 56.6% of the fractured instruments occurred in severely curved canals, and the apical third of the root canal was the most common site for instrument fracture (85.7%), followed by middle (13.2%), and coronal (1.1%) thirds, mostly with file sizes 20 and 25 (59.9% and 25.27%, respectively). CONCLUSION The fracture incidence of K3 instruments was significantly greater during root canal re-treatment than root canal treatment, mainly with small instruments and in the apical third of the canals.
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Affiliation(s)
- K Alfouzan
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Restorative and Prosthetic Dental Sciences, College of Dentistry, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - A Jamleh
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Restorative and Prosthetic Dental Sciences, College of Dentistry, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
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Iacono F, Pirani C, Generali L, Bolelli G, Sassatelli P, Lusvarghi L, Gandolfi MG, Giorgini L, Prati C. Structural analysis of HyFlex EDM instruments. Int Endod J 2016; 50:303-313. [DOI: 10.1111/iej.12620] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/08/2016] [Indexed: 11/29/2022]
Affiliation(s)
- F. Iacono
- Endodontic Clinical Section; Department of Biomedical and Neuromotor Sciences (DIBINEM); University of Bologna; Bologna Italy
| | - C. Pirani
- Endodontic Clinical Section; Department of Biomedical and Neuromotor Sciences (DIBINEM); University of Bologna; Bologna Italy
| | - L. Generali
- Endodontic Section; Department of Surgery, Medicine, Dentistry and Morphological Sciences with Transplant Surgery; Oncology and Regenerative Medicine Relevance (CHIMOMO); School of Dentistry; University of Modena and Reggio Emilia; Modena Italy
| | - G. Bolelli
- Department of Engineering “Enzo Ferrari” (DIEF); University of Modena and Reggio Emilia; Modena Italy
| | - P. Sassatelli
- Department of Engineering “Enzo Ferrari” (DIEF); University of Modena and Reggio Emilia; Modena Italy
| | - L. Lusvarghi
- Department of Engineering “Enzo Ferrari” (DIEF); University of Modena and Reggio Emilia; Modena Italy
| | - M. G. Gandolfi
- Endodontic Clinical Section; Department of Biomedical and Neuromotor Sciences (DIBINEM); University of Bologna; Bologna Italy
| | - L. Giorgini
- Department of Industrial Chemistry “Toso Montanari” and INSTM UdR-Bologna; University of Bologna; Bologna Italy
| | - C. Prati
- Endodontic Clinical Section; Department of Biomedical and Neuromotor Sciences (DIBINEM); University of Bologna; Bologna Italy
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Performance of NiTi endodontic instrument under different temperatures. Odontology 2015; 104:324-8. [DOI: 10.1007/s10266-015-0214-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 06/10/2015] [Indexed: 10/23/2022]
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Jamleh A, Sadr A, Nomura N, Ebihara A, Yahata Y, Hanawa T, Tagami J, Suda H. Endodontic instruments after torsional failure: nanoindentation test. SCANNING 2014; 36:437-443. [PMID: 24610598 DOI: 10.1002/sca.21139] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/24/2014] [Indexed: 06/03/2023]
Abstract
This study aimed to evaluate effects of torsional loading on the mechanical properties of endodontic instruments using the nanoindentation technique. ProFile (PF; size 30, taper 04; Dentsply Maillefer, Switzerland) and stainless steel (SS; size 30, taper 02; Mani, Japan) instruments were subjected to torsional test. Nanoindentation was then performed adjacent to the edge of fracture (edge) and at the cutting part beside the shank (shank). Hardness and elastic modulus were measured under 100-mN force on 100 locations at each region, and compared to those obtained from the same regions on new instruments. It showed that PF and SS instruments failed at 559 ± 67 and 596 ± 73 rotation degrees and mean maximum torque of 0.90 ± 0.07 and 0.99 ± 0.05 N-cm, respectively. Hardness and elastic modulus ranged 4.8-6.7 and 118-339 GPa in SS, and 2.7-3.2 and 52-81 GPa in PF. Significant differences between torsion-fractured and new instruments in hardness and elastic modulus were detected in the SS system used. While in PF system, the edge region after torsional fracture had significantly lower hardness and elastic modulus compared to new instruments. The local hardness and modulus of elasticity of endodontic instruments adjacent to the fracture edge are significantly reduced by torsional loading.
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Affiliation(s)
- Ahmed Jamleh
- Department of Endodontics, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, National Guard Health Affairs, Riyadh, Saudi Arabia
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Shen Y, Zhou H, Campbell L, Wang Z, Wang R, Du T, Haapasalo M. Fatigue and nanomechanical properties of K3XF nickel-titanium instruments. Int Endod J 2014; 47:1160-7. [DOI: 10.1111/iej.12265] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 02/06/2014] [Indexed: 11/26/2022]
Affiliation(s)
- Y. Shen
- Division of Endodontics; Department of Oral Biological and Medical Sciences; Faculty of Dentistry; The University of British Columbia; Vancouver BC Canada
- Department of Materials Engineering; The University of British Columbia; Vancouver BC Canada
| | - H. Zhou
- Center for Biomedical Materials and Engineering; College of Material Science and Chemical Engineering; Harbin Engineering University; Harbin China
| | - L. Campbell
- Division of Endodontics; Department of Oral Biological and Medical Sciences; Faculty of Dentistry; The University of British Columbia; Vancouver BC Canada
| | - Z. Wang
- Division of Endodontics; Department of Oral Biological and Medical Sciences; Faculty of Dentistry; The University of British Columbia; Vancouver BC Canada
| | - R. Wang
- Department of Materials Engineering; The University of British Columbia; Vancouver BC Canada
| | - T. Du
- Department of Stomatology; Tongji Hospital; Tongji Medical College; Huazhong University of Science and Technology; Wuhan China
| | - M. Haapasalo
- Division of Endodontics; Department of Oral Biological and Medical Sciences; Faculty of Dentistry; The University of British Columbia; Vancouver BC Canada
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MIYARA K, YAHATA Y, HAYASHI Y, TSUTSUMI Y, EBIHARA A, HANAWA T, SUDA H. The influence of heat treatment on the mechanical properties of Ni-Ti file materials. Dent Mater J 2014; 33:27-31. [DOI: 10.4012/dmj.2013-196] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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PIAO J, MIYARA K, EBIHARA A, NOMURA N, HANAWA T, SUDA H. Correlation between cyclic fatigue and the bending properties of nickel titanium endodontic instruments. Dent Mater J 2014; 33:539-44. [DOI: 10.4012/dmj.2013-318] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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