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Chicon JB, Fernandes Pavão VM, Gonçalves Cunha MH, Frozoni M. Influence of the Brushing Motions on the Dynamic Cyclic Fatigue Resistance of the Reciproc Blue Instrument: In vitro Study. J Endod 2024; 50:1340-1345. [PMID: 38964675 DOI: 10.1016/j.joen.2024.06.013] [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: 02/12/2024] [Revised: 06/22/2024] [Accepted: 06/24/2024] [Indexed: 07/06/2024]
Abstract
INTRODUCTION This study aimed to evaluate the dynamic cyclic fatigue resistance of Reciproc Blue files subjected to brushing motion. METHODS Twenty Reciproc Blue files (R25, VDW, Munich, Germany) were employed for chemical-mechanical preparation in root canals of 3D printed replicas of mandibular molars. The instruments were divided into two groups (n = 10): Group brushing motion, instrumentation with brushing motions; Group without brushing motion , instrumentation without brushing motions. Subsequently, the same instruments underwent cyclic fatigue testing using artificial canals consisting of a stainless-steel plate and an apical segment with a 45° curvature. Data regarding the time to fracture, number of cycles to fracture, and length of the fractured fragment were collected and subjected to statistical analysis using the t-test or Mann-Whitney test, with a significance level of 5%. Additionally, the fractured fragments were examined under a scanning electron microscope. RESULTS No statistical differences were observed between the groups in terms of time to fracture (P < .05), number of cycles to fracture (P < .05) and length of the fractured fragment (P < .05). CONCLUSION The brushing motion did not affect the dynamic cyclic fatigue resistance of Reciproc Blue files.
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Affiliation(s)
- Juliana Borsoi Chicon
- Department of Endodontic, São Leopoldo Mandic School of Dentistry, Campinas, SãP Paulo, Brazil.
| | | | | | - Marcos Frozoni
- Department of Endodontic, São Leopoldo Mandic School of Dentistry, Campinas, SãP Paulo, Brazil
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Surme K, Akman H, Özkan HB, Er K. Comparison of cyclic fatigue resistance of four pediatric rotary file systems at body temperature: an in vitro study. BMC Oral Health 2024; 24:992. [PMID: 39180032 PMCID: PMC11344432 DOI: 10.1186/s12903-024-04739-z] [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: 01/31/2024] [Accepted: 08/13/2024] [Indexed: 08/26/2024] Open
Abstract
BACKGROUND The aim of this study was to compare the cyclic fatigue resistance (CFR) of the newly developed pediatric nickel-titanium (NiTi) rotary file systems for root canal preparation of primary teeth. METHODS Eighty pediatric NiTi rotary file systems files were used in this study, including 20 EasyInSmile X-Baby (25/0.04), 20 Scope miniScope (25/0.04), 20 EndoArt Pedo Gold (25/0.04), and 20 EndoArt Pedo Blue (25/0.04) files. Static CFR tests; performed on a custom-made stainless steel block with an inner diameter of 1.5 mm, an angle of curvature of 60° and a curved artificial canal with a radius of curvature of 5 mm. The test system was filled with distilled water and the temperature was kept constant at 35 ± 1 °C. The files were rotated in the simulated canal until fracture occurred. The number of cycles to failure (NCF) data was recorded, and all the fracture surfaces of the files were evaluated using scanning electron microscopy (SEM). One-way ANOVA and Tukey tests were used for statistical analysis of the data, and the significance level was set at p < 0.05. RESULTS EndoArt Pedo Blue showed the highest NCF values (2668.10 ± 755.26), while the miniScope showed the lowest NCF values (453.65 ± 72.51), with a statistically significant difference between all the tested file systems (p < 0.05). There was no statistical difference in terms of fractured fragment lengths among all tested files (p > 0.05). CONCLUSION The EndoArt Pedo Blue file system showed the best CFR performance among the four file systems specifically designed for primary teeth.
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Affiliation(s)
- Koray Surme
- Department of Paediatric Dentistry, Faculty of Dentistry, Alanya Alaaddin Keykubat University, Antalya, 07400, Turkey
| | - Hayri Akman
- Department of Paediatric Dentistry, Faculty of Dentistry, Alanya Alaaddin Keykubat University, Antalya, 07400, Turkey.
| | - Hatice Büyüközer Özkan
- Department of Endodontics, Faculty of Dentistry, Alanya Alaaddin Keykubat University, Antalya, Turkey
| | - Kürşat Er
- Department of Endodontics, Faculty of Dentistry, Akdeniz University, Antalya, Turkey
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Immich F, de Araújo LP, da Gama RR, da Rosa WLDO, Piva E, Rossi-Fedele G. Fifteen years of engine-driven nickel-titanium reciprocating instruments, what do we know so far? An umbrella review. AUST ENDOD J 2024; 50:409-463. [PMID: 38923176 DOI: 10.1111/aej.12870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024]
Abstract
Numerous systematic reviews (SRs) have produced conflicting findings on engine-driven nickel-titanium reciprocating instruments (reciprocating instruments) since Yared's seminal study 15 years ago. This umbrella review analysed SRs examining the clinical and laboratory evidence regarding reciprocating instruments for root canal treatment. SRs that evaluated qualitatively and/or quantitatively the outcomes postoperative pain, oral health-related quality of life (OHRQoL), shaping ability, debris extrusion, microbial load, endotoxins reduction, cyclic fatigue, file fracture, dentinal cracks and root canal filling removal were included. The AMSTAR 2 tool was used to evaluate SRs quality, while the ROBIS tool to assess risk of bias (RoB). Forty SRs were included. The SRs revealed predominantly 'high' RoB and 'critically low' quality. Most focused on technical outcomes, exhibiting significant methodological and statistical heterogeneity. Findings suggest comparable efficacy between reciprocating and rotary instruments. However, due to the scarcity of high-quality evidence, future well-designed studies and reviews considering core outcome measures are needed.
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Affiliation(s)
- Felipe Immich
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, Brazil
| | - Lucas Peixoto de Araújo
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, Brazil
- School of Dentistry, Catholic University of Pelotas, Pelotas, Brazil
| | | | | | - Evandro Piva
- Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, Brazil
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Abdellatif D, Iandolo A, Scorziello M, Sangiovanni G, Pisano M. Cyclic Fatigue of Different Ni-Ti Endodontic Rotary File Alloys: A Comprehensive Review. Bioengineering (Basel) 2024; 11:499. [PMID: 38790365 PMCID: PMC11118078 DOI: 10.3390/bioengineering11050499] [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: 04/18/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
INTRODUCTION Modern endodontics aims to decrease the bacterial load from the complex endodontic space. Over the years, improvements in the operative phases have led to a considerable increase in the success rate of endodontic treatments. The shaping phase has seen the development of new techniques supported by technological innovations that have led to higher treatment predictability. Endodontic instruments have experienced a series of changes that have led to modifications in their design, surface treatments, and heat treatments. The clinical use of rotating nickel-titanium instruments has become widespread and consolidated, a success due primarily to the alloy's mechanical characteristics, which are superior to steel ones, but also to innovations in instrument design. The advent of the Ni-Ti alloy has kept the concepts and requirements of shaping the same but has modified its implementation in endodontics. AIM The following review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) protocol. The research question focused on Ni-Ti endodontic instruments whose cyclic fatigue was evaluated by analyzing cyclic fatigue strength and the incidence of fracture. RESULTS At the end of the research, 10 systematic reviews and 1 randomized controlled trial were included in this comprehensive review. The most frequently analysed alloys were M-wire, conventional Ni-Ti, and CM-wire. In seven articles, instruments made of M-wire alloy were used; in eight articles, instruments made of conventional Ni-Ti; and in seven articles, instruments made of CM-wire alloy. CONCLUSIONS The technological evolution of Ni-Ti alloys has led to the development of increasingly high-performance endodontic files that are resistant to cyclic fatigue during clinical practice and have greater resistance to sterilisation practices, making treatment easier and more predictable over time. In particular, heat-treated nickel-titanium root canal instruments present greater resistance to cyclic fatigue than untreated ones and those used with reciprocating kinematics concerning continuous rotation.
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Affiliation(s)
| | | | | | | | - Massimo Pisano
- Department of Medicine, Surgery and Dentistry “Scuola Medica Salernitana”, University of Salerno, 84081 Baronissi, Italy (A.I.); (M.S.); (G.S.)
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Rego LF, Bronzato JD, Souza APC, de-Jesus-Soares A, Frozoni M. In Vitro Evaluation of the Dynamic Cyclic Fatigue Resistance of a New TruNatomy Glider File after Different Cycles of Use. J Endod 2024; 50:619-626. [PMID: 38311114 DOI: 10.1016/j.joen.2024.01.021] [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: 08/08/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/06/2024]
Abstract
INTRODUCTION Determination of the glide path is recommended before using rotary instruments. This study aimed to evaluate the dynamic cyclic fatigue resistance of new and used glider rotary instruments in up to 6 root canals. METHODS Seventy-two TruNatomy Glider files were used for the preparation of root canals of extracted lower molars, which were then submitted to the dynamic cyclic fatigue test carried out in a curved metallic artificial canal. The instruments were divided into 4 groups (n = 18): Control group, new instruments without any use in the root canal; Group 2U, instruments used in 2 mesial canals; Group 4U, instruments used in 4 mesial canals; Group 6U, instruments used in 6 mesial canals. The time to failure (TF) of the instrument was recorded, and the number of cycles to failure (NCF) was calculated. The data were submitted to 1-way analysis of variance and to the Games-Howell test for multiple comparisons, adopting a significance level of 5%. RESULTS TF and NCF were significantly affected by the number of file uses. The Games-Howell test revealed that TF and NCF were significantly greater in the control group than in Group 4U. In Group 2U, TF and NCF were intermediate and not significantly different from the control group. Group 6U had significantly lower TF and NCF than all other groups. CONCLUSION The TruNatomy Glider can be used as a glide path for up to 2 mesial canals of mandibular molars, whereas its use on 4 or 6 root canals is not suggested.
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Affiliation(s)
- Lorena Ferreira Rego
- Department of Endodontics, São Leopoldo Mandic School of Dentistry, Campinas, São Paulo, Brazil
| | - Juliana Delatorre Bronzato
- Division of Endodontics, Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
| | | | - Adriana de-Jesus-Soares
- Division of Endodontics, Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil
| | - Marcos Frozoni
- Department of Endodontics, São Leopoldo Mandic School of Dentistry, Campinas, São Paulo, Brazil
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Allahem Z, Bendahmash M, Almeaither R, Alfawaz H, Alqedairi A. Evaluation of cyclic fatigue behavior of RACE EVO rotary Files: In-vitro comparative study. Saudi Dent J 2024; 36:656-660. [PMID: 38690374 PMCID: PMC11056425 DOI: 10.1016/j.sdentj.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/11/2024] [Accepted: 03/11/2024] [Indexed: 05/02/2024] Open
Abstract
Introduction Comparative evaluation of the newly introduced; RACE EVO file system to the currently well-performing file systems like HyFlex EDM OneFile, Vortex Blue, ProTaper Gold (PTG) with regards to the cyclic fatigue resistance. Materials &Methods.The endodontic rotary files under evaluation were segregated into four groups as follows:; RACE EVO, PTG, Vortex Blue, and HyFlex EDM OneFile. A detailed physical analysis of the cyclic fatigue resistance was performed in 15 files of each type (n = 60). Under the test conditions of 37 °C the test samples were subjected to continuous motion at the manufacturer recommended speed within an artificial curved canal until it fractured. For all the test samples, with the recording of time of fracture, calculation was done for number of cycles to fracture (NCF). In addition, the length of the fractured segment was determined. The fractured surface was further evaluated with scanning electron microscopic (SEM) images. Results Highest significance for NCF was seen in HyFlex EDM OneFile followed by the Vortex Blue, PTG, and; RACE EVO (p < 0.05) by analyzing the data statistically. Significant differences among the lengths of the fractured segments were evident among tested files, ranging between 4.73 and 6.3 mm (p < 0.05) with HyFlex EDM OneFile uniquely differentiating from the others showing the fracture at 6.3 mm. The common features of cyclic fatigue failure was further substantiated by SEM images. Conclusions Compared to the HyFlex EDM OneFile, Vortex Blue, and PTG files; RACE EVO demonstrated significantly lower resistance to cyclic fatigue.
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Affiliation(s)
- Ziyad Allahem
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Bendahmash
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Reem Almeaither
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Hussam Alfawaz
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Abdullah Alqedairi
- Department of Restorative Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
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Hamid T, Malik A, Kumar A, Anjum S. Comparative evaluation of cyclic fatigue resistance of thermomechanically treated NiTi rotary instruments in simulated curved canals with two different radii of curvature: An in vitro Study. JOURNAL OF CONSERVATIVE DENTISTRY AND ENDODONTICS 2024; 27:393-399. [PMID: 38779209 PMCID: PMC11108414 DOI: 10.4103/jcde.jcde_32_24] [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: 01/14/2024] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 05/25/2024]
Abstract
Background This study aimed to compare the effect of heat treatment on the cyclic fatigue resistance of three different nickel-titanium rotary file systems: TruNatomy, HyFlex CM, and NeoEndo flex in simulated curved canals at two different radii of curvatures. Materials and Methods A total of 60 NiTi rotary files of three types were used, and the samples were divided into three groups TruNatomy, HyFlex CM, and NeoEndo flex. All the instruments were subjected to cyclic fatigue testing using a stainless steel custom-made canal model with a 60° angle of curvature and two radii of curvature 5 mm and 3 mm; the number of cycles to fracture and length of the fractured segment was measured. The separated instruments were subjected to fractographic analysis under scanning electron microscope. Results The number of cycles to failure to fracture a file at a 3 mm radius of curvature is significantly less as compared to a 5 mm radius of curvature (HCM > TRN > NE). Conclusion Within the limitation of the present study, there was a positive correlation between the radius of curvature and fatigue life of NiTi files.
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Affiliation(s)
- Tahira Hamid
- Department of Conservative Dentistry and Endodontics, Indira Gandhi Government Dental College, Jammu, Jammu and Kashmir, India
| | - Azhar Malik
- Department of Conservative Dentistry and Endodontics, Indira Gandhi Government Dental College, Jammu, Jammu and Kashmir, India
| | - Ajay Kumar
- Department of Conservative Dentistry and Endodontics, Indira Gandhi Government Dental College, Jammu, Jammu and Kashmir, India
| | - Shamim Anjum
- Department of Conservative Dentistry and Endodontics, Indira Gandhi Government Dental College, Jammu, Jammu and Kashmir, India
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Pedullà E, Carlesi T, Pappalardo A, Canova FS, Malagnino VA, La Rosa GRM, Generali L. Impact of pecking amplitude on cyclic fatigue of new nickel-titanium files. Clin Exp Dent Res 2024; 10:e811. [PMID: 38053521 PMCID: PMC10860459 DOI: 10.1002/cre2.811] [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: 09/18/2023] [Revised: 10/31/2023] [Accepted: 11/05/2023] [Indexed: 12/07/2023] Open
Abstract
OBJECTIVES The aim of this study is to determine the cyclic fatigue resistance of Mtwo Minimal in static and dynamic tests, with different amplitudes of pecking movements, at intracanal temperature. MATERIALS AND METHODS Two hundred new 25-mm Mtwo Minimal rotary files (#10/0.035, #17.5/0.045, #25/0.05, #40/0.03, #45/0.03) were tested in static and dynamic cyclic fatigue tests at 35°C (±1°C). An artificial stainless-steel canal was used. In the dynamic mode, axial movements were set at 1 and 3 mm. The number of cycles to fracture (NCF) was recorded and statistically analyzed by one-way analysis of variance (p < 0.05). RESULTS The 3-mm dynamic test showed significantly increased NCF than the other tests for the #10/0.035, #17.5/0.045, and #25/0.05 files (p < 0.05). The #40/0.03 and #45/0.03 files showed no significant differences in all the tests (p > 0.05). CONCLUSION Mtwo Minimal showed higher cyclic fatigue resistance in the dynamic test than the static test, except for the larger instruments. The 3-mm pecking amplitude increased the cyclic fatigue resistance of the smaller instruments.
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Affiliation(s)
- Eugenio Pedullà
- Department of General Surgery and Medical‐Surgical SpecialtiesUniversity of CataniaCataniaItaly
| | - Teocrito Carlesi
- Department of Medical, Oral and Biotechnological Sciences, Faculty of Medicine and SurgeryUniversity of Chieti—Pescara “G. D'Annunzio”ChietiItaly
- Department of Innovative Technologies in Medicine and Dentistry, Faculty of Medicine and SurgeryUniversity of Chieti—Pescara “G. D'Annunzio”ChietiItaly
| | | | | | - Vito Antonio Malagnino
- Department of Innovative Technologies in Medicine and Dentistry, Faculty of Medicine and SurgeryUniversity of Chieti—Pescara “G. D'Annunzio”ChietiItaly
| | | | - Luigi Generali
- Department of Surgery, Medicine, Dentistry and Morphological Sciences with Transplant Surgery, Oncology and Regenerative Medicine RelevanceUniversity of Modena and Reggio EmiliaModenaItaly
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Youssef E, Jungbluth H, Jepsen S, Gruener M, Bourauel C. Comparing Cyclic Fatigue Resistance and Free Recovery Transformation Temperature of NiTi Endodontic Single-File Systems Using a Novel Testing Setup. MATERIALS (BASEL, SWITZERLAND) 2024; 17:566. [PMID: 38591373 PMCID: PMC10856488 DOI: 10.3390/ma17030566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/05/2024] [Accepted: 01/22/2024] [Indexed: 04/10/2024]
Abstract
The aim of this study was to assess the effect of body temperature (37 °C) on the cyclic fatigue resistance of three endodontic single-file systems using a new testing setup. One Shape® new generation (OS), WaveOne™ (WO) and WaveOne® GOLD (WOG), which are made from different NiTi alloys and operated in different motions (rotation/reciprocation), were evaluated. The study design included four groups. Each group comprised 30 files, 10 files of each of the three file systems, tested at 20 ± 2 °C (group 1 and 3) and at 37 ± 1 °C (group 2 and 4). All files were tested in a custom-made metal block with artificial canals of 60° angle, and a 5 mm and 3 mm radius of curvature, respectively. A heating element was attached to replicate a temperature of 37 °C. Files were introduced 18 mm into the canals and operated until failure. Transformation temperatures of five samples of each of the tested file systems were determined via the bend and free recovery (BFR) method. With the exception of WOG in canals with a 3 mm radius of curvature (p = 0.075), all the tested file systems showed statistically significantly less time needed to fracture when operated at 37 ± 1 °C compared to at 20 ± 2 °C in canals with a 5 mm and 3 mm radius of curvature using Mann-Whitney U test (p < 0.05). All file systems showed transformation temperatures below the body temperature. We concluded that body temperature directly affects the cyclic fatigue resistance of all tested file systems. Bend and free recovery can be suitable for the determination of austenite finish temperatures (Af) of endodontic instruments as it allows testing a longer portion of the instrument.
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Affiliation(s)
- Emad Youssef
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
- Department of Oral Technology, Faculty of Medicine, University of Bonn, 53111 Bonn, Germany
| | - Holger Jungbluth
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
| | - Søren Jepsen
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, 53111 Bonn, Germany
| | - Manfred Gruener
- Department of Oral Technology, Faculty of Medicine, University of Bonn, 53111 Bonn, Germany
| | - Christoph Bourauel
- Department of Oral Technology, Faculty of Medicine, University of Bonn, 53111 Bonn, Germany
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Weissheimer T, Duarte MAH, Só MVR, da Rosa RA, Espinosa MK, Vivan RR, Alcalde MP. Evaluation of cyclic and torsional fatigue resistance of several heat-treated reciprocating nickel-titanium instruments. AUST ENDOD J 2023; 49:524-529. [PMID: 37439395 DOI: 10.1111/aej.12774] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 06/14/2023] [Accepted: 07/03/2023] [Indexed: 07/14/2023]
Abstract
This study investigated the cyclic fatigue and torsional resistance of Unicone Plus (UCP 25.06), Unicone (UC 25.06), Reciproc Blue (RB 25.08) and Wave One Gold (WOG 25.07) performed at body temperature (35° ± 1°C). Time and number of cycles to fracture (NCF), as well as torque and angular deflection were recorded. Fractured surfaces were evaluated by scanning electron microscopy (SEM). Data were analysed using one-way ANOVA and Holm-Sidak's tests for multiple comparison. The RB had a significantly higher time to fracture, followed by the WOG and UCP (p < 0.05). Regarding the NCF, there was no significantly difference between RB and WOG (p > 0.05). UC presented highest torque values and the lowest angular deflection (p < 0.05). SEM analysis demonstrated typical failures features in both cyclic and torsional fatigue tests. Overall, UC had the lowest time, NCF and angular deflection at fracture. RB presented the highest time to fracture and angular deflection values.
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Affiliation(s)
- Theodoro Weissheimer
- Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Marco Antonio Húngaro Duarte
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Marcus Vinicius Reis Só
- Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Ricardo Abreu da Rosa
- Department of Conservative Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Michel Klymus Espinosa
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Rodrigo Ricci Vivan
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
| | - Murilo Priori Alcalde
- Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
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