Due to planned maintenance work on our platforms, there might be short service disruptions on Saturday, December 3rd, between 15:00 and 16:00 (CET).
materials-logo

Journal Browser

Journal Browser

Special Issue "Advances and Applications of Nickel-Titanium Alloys in Medical Fields"

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Biomaterials".

Deadline for manuscript submissions: 20 December 2022 | Viewed by 5559

Special Issue Editor

Dr. Jorge Nuno do Martins
E-Mail Website
Guest Editor
School of Dental Medicine, University of Lisbon, 1600-277 Lisbon, Portugal
Interests: endodontics; tooth anatomy; NiTi instruments; NiTi alloys; cone-beam computed tomography; prevalence studies
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Since the observation of shape memory characteristics in an almost equiatomic nickel-titanium (NiTi) alloy in research developed for the United States of America Navy, NiTi alloys have been employed not only in ocean engineering but also in medical fields, with applications in orthopedics, orthodontics, and endodontics. The almost equiatomic proportion of the main two elements leads to a weight proportion of around 56% nickel and 44% titanium. As with other metallic alloys, the NiTi alloy can exist in several crystallographic arrangements. The changes in the alloy arrangement may result from stress application or temperature effects. Due to their characteristics, NiTi alloys have been recurrently used in the manufacture of medical tools and instruments. This Special Issue intends to provide an overview of the latest advances, tendencies, and applications of this alloy in multiple areas of different medical fields. It is my pleasure to invite you to contribute to this Special Issue, where both research papers and reviews, with a focus on the following potential topics, are welcome. Potential topics include, but are not limited to: novel medical applications; advances in technical procedures; new technologies and recent developments in manufacturing; mechanical properties and novel modes to assess them; new concepts, and historical and future perspectives.

Dr. Jorge N.R. Martins
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2300 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • mechanical properties
  • metal alloys
  • metallurgy
  • nickel/titanium alloys
  • phase transformation
  • strength
  • structural characterization

Published Papers (6 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Article
Mechanical and Metallurgical Characterization of Nickel-Titanium Wire Types for Rotary Endodontic Instrument Manufacture
Materials 2022, 15(23), 8367; https://doi.org/10.3390/ma15238367 - 24 Nov 2022
Viewed by 291
Abstract
This study aimed to evaluate and compare the effects of ambient temperature and post-manufacture heat-treatment on the mechanical behavior of nickel-titanium (NiTi) wires. Four types of commercial NiTi variants (Stock NiTi, heat treated “Blue”, “Gold”, “Superflex”, all Dentsply Maillefer, Ballaigues, Switzerland) were stressed [...] Read more.
This study aimed to evaluate and compare the effects of ambient temperature and post-manufacture heat-treatment on the mechanical behavior of nickel-titanium (NiTi) wires. Four types of commercial NiTi variants (Stock NiTi, heat treated “Blue”, “Gold”, “Superflex”, all Dentsply Maillefer, Ballaigues, Switzerland) were stressed in a tensile testing machine in a temperature-controlled water bath at three different temperatures. Stress and strain values were extrapolated from the raw data, and 2-way ANOVA and Tukey’s test for multiple comparisons were performed to compare the differences of the mechanical constants. Differential scanning calorimetry (DSC) tests established the martensitic transformation starting (Ms), finishing (Mf) and austenitic (reverse-martensitic) starting (As) and finishing (Af) points. Austenitic modulus of elasticity and transformation stress values increased with temperature for all NiTi groups. The martensitic modulus of elasticity, maximum transformation strain and ultimate tensile stress were not significantly affected by temperature changes. Stock NiTi and Gold wire samples presented with clearly delineated austenitic and martensitic transformations in the DSC experiments. Differences in manufacturing/heat treatment conditions and ambient temperature affect the mechanical behavior of nickel-titanium and may have clinical implications. Further improvements to the experimental setup could be considered to provide more accurate measurements of strain. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Article
A Multimethod Assessment of a New Customized Heat-Treated Nickel–Titanium Rotary File System
Materials 2022, 15(15), 5288; https://doi.org/10.3390/ma15155288 - 31 Jul 2022
Cited by 2 | Viewed by 840
Abstract
This study aimed to compare three endodontic rotary systems. The new Genius Proflex (25/0.04), Vortex Blue (25/0.04), and TruNatomy (26/0.04v) instruments (n = 41 per group) were analyzed regarding design, metallurgy, and mechanical performance, while shaping ability (untouched canal walls, volume of removed [...] Read more.
This study aimed to compare three endodontic rotary systems. The new Genius Proflex (25/0.04), Vortex Blue (25/0.04), and TruNatomy (26/0.04v) instruments (n = 41 per group) were analyzed regarding design, metallurgy, and mechanical performance, while shaping ability (untouched canal walls, volume of removed dentin and hard tissue debris) was tested in 36 anatomically matched root canals of mandibular molars. The results were compared using one-way ANOVA, post hoc Tukey, and Kruskal–Wallis tests, with a significance level set at 5%. All instruments showed symmetrical cross-sections, with asymmetrical blades, no radial lands, no major defects, and almost equiatomic nickel–titanium ratios. Differences were noted in the number of blades, helical angles, cross-sectional design, and tip geometry. The Genius Proflex and the TruNatomy instruments had the highest and lowest R-phase start and finish temperatures, as well as the highest and lowest time and cycles to fracture (p < 0.05), respectively. The TruNatomy had the highest flexibility (p < 0.05), while no differences were observed between the Genius Proflex and the Vortex Blue (p > 0.05). No differences among tested systems were observed regarding the maximum torque, angle of rotation prior to fracture, and shaping ability (p > 0.05). The instruments showed similarities and differences in their design, metallurgy, and mechanical properties. However, their shaping ability was similar, without any clinically significant errors. Understanding these characteristics may help clinicians to make decisions regarding which instrument to choose for a particular clinical situation. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Article
A Novel Alveolar Distractor Incorporating Nickel–Titanium Alloy Springs: A Preliminary In Vitro Study
Materials 2022, 15(15), 5151; https://doi.org/10.3390/ma15155151 - 25 Jul 2022
Viewed by 600
Abstract
A new design of an alveolar distractor using nickel–titanium (NiTi) open-coil springs was developed and investigated to produce distraction forces against the tensile forces of porcine attached gingiva to simulate human gingiva. We subjected 15 mm long NiTi open-coil springs (Highland and ORMCO) [...] Read more.
A new design of an alveolar distractor using nickel–titanium (NiTi) open-coil springs was developed and investigated to produce distraction forces against the tensile forces of porcine attached gingiva to simulate human gingiva. We subjected 15 mm long NiTi open-coil springs (Highland and ORMCO) with three levels of forces (light, medium and heavy) to mechanical testing in a 37 ± 1 °C water bath. Ten strips of porcine mandibular attached gingiva were subjected to tensile tests to determine the resistance force. The forces from the springs were compared with the tensile forces from the porcine attached gingiva. Data between groups were analyzed with independent-samples T-tests (p-value < 0.05). The tensile strength and the Young modulus were greater in buccal compared to lingual porcine attached gingiva. Compared to other spring dimensions and companies, forces generated from 0.014 × 0.036″ ORMCO springs were the highest and could overcome the tensile resistance from porcine attached gingiva over the longest distraction range of 1.6 mm. This preliminary in vitro study introduced a new design of an alveolar distractor incorporated with NiTi open-coil springs that could generate light and continuous forces to overcome the resistance from porcine attached gingiva. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Article
Multimethod Assessment of Design, Metallurgical, and Mechanical Characteristics of Original and Counterfeit ProGlider Instruments
Materials 2022, 15(11), 3971; https://doi.org/10.3390/ma15113971 - 02 Jun 2022
Viewed by 572
Abstract
A multimethod study was conducted to assess the differences between original (PG-OR) and counterfeit (PG-CF) ProGlider instruments regarding design, metallurgical features, and mechanical performance. Seventy PG-OR and PG-CF instruments (n = 35 per group) were evaluated regarding the number of spirals, helical angles, [...] Read more.
A multimethod study was conducted to assess the differences between original (PG-OR) and counterfeit (PG-CF) ProGlider instruments regarding design, metallurgical features, and mechanical performance. Seventy PG-OR and PG-CF instruments (n = 35 per group) were evaluated regarding the number of spirals, helical angles, and measuring line position by stereomicroscopy, while blade symmetry, cross-section geometry, tip design, and surface were assessed by scanning electron microscopy. Energy-dispersive X-ray spectroscopy and differential scanning calorimetry were used to identify element ratio and phase transformation temperatures, while cyclic fatigue, torsional, and bending testing were employed to assess their mechanical performance. An unpaired t-test and nonparametric Mann–Whitney U test were used to compare instruments at a significance level of 5%. Similarities were observed in the number of spirals, helical angles, blade symmetry, cross-sectional geometries, and nickel–titanium ratios. Measuring lines were more reliable in the original instrument, while differences were noted in the geometry of the tips (sharper tip for the original and rounded for the counterfeit) and surface finishing with PG-CF presenting more surface irregularities. PG-OR showed significantly more time to fracture (118 s), a higher angle of rotation (440°), and a lower maximum bending load (146.3 gf) (p < 0.05) than PG-CF (p < 0.05); however, maximum torque was similar for both instruments (0.4 N.cm) (p > 0.05). Although the tested instruments had a similar design, the original ProGlider showed superior mechanical behavior. The results of counterfeit ProGlider instruments were unreliable and can be considered unsafe for glide path procedures. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Article
Comparative Assessment of the Shaping Ability of Reciproc Blue, WaveOne Gold, and ProTaper Gold in Simulated Root Canals
Materials 2022, 15(9), 3028; https://doi.org/10.3390/ma15093028 - 21 Apr 2022
Viewed by 804
Abstract
Maintaining the original trajectory of the root canal is a major challenge in endodontic therapy, especially in narrow and curved root canals. The present study aims to assess the shaping capacity of three endodontic systems made of different nickel–titanium alloys on simulated curved [...] Read more.
Maintaining the original trajectory of the root canal is a major challenge in endodontic therapy, especially in narrow and curved root canals. The present study aims to assess the shaping capacity of three endodontic systems made of different nickel–titanium alloys on simulated curved root canals. Thirty-six endodontic resin blocks (Ref. V040245, VDW) divided into three groups, each of twelve blocks (n = 12), were shaped, photographed, and analyzed: Group 1-Protaper Gold (PTG) (Dentsply Maillefer, Ballaigues, Switzerland) F2 25/08; Group 2-Reciproc Blue (RB), RB 25/08 (VDW, Munich, Germany); Group 3-WaveOne Gold (WOG) (Dentsply Maillefer), WOG 25/07. Each block was standardized and photographed before and after shaping in the same position, with the foramen oriented to the left. Post-shaping images were superimposed onto the initial ones. Thirteen measurement points were used for evaluation, spaced with 1 mm distance from one another, from level 0, apical foramen, to level 12, coronal orifice. The amount of removed resin from inner (X1) and outer (X2) walls, the direction of transportation (X1 − X2), and the centering ability (X1 − X2)/Y were measured, calculated, and comparatively analyzed. Statistical differences (p < 0.05) were observed between the shaping capacity of the considered systems in the middle and coronal thirds. PTG had a better centering ability than WOG and RB in the coronal third, while RB was more centered in the middle third in comparison to both WOG and PTG. In the apical third, the centering capacity of WOG was higher, without being statistically significant. WOG 25/07 and PTG 25/08 tend to cut more on the inner wall of the root canals, and RB 25/08 on the external one. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Article
Design, Metallurgical Features, and Mechanical Behaviour of NiTi Endodontic Instruments from Five Different Heat-Treated Rotary Systems
Materials 2022, 15(3), 1009; https://doi.org/10.3390/ma15031009 - 28 Jan 2022
Cited by 7 | Viewed by 1947
Abstract
The current study aimed to compare the F1 endodontic instruments from five different heat-treated rotary systems regarding their design, metallurgical properties, and mechanical performance. Five F1 root canal shaping instruments (ProTaper Gold [PTG], Premium Taper Gold, Go-Taper Flex, EdgeTaper Platinum, and Super Files [...] Read more.
The current study aimed to compare the F1 endodontic instruments from five different heat-treated rotary systems regarding their design, metallurgical properties, and mechanical performance. Five F1 root canal shaping instruments (ProTaper Gold [PTG], Premium Taper Gold, Go-Taper Flex, EdgeTaper Platinum, and Super Files Blue)—plus, a conventional ProTaper Universal (PTU)—which were evaluated regarding their design, nickel/titanium ratio, phase transformation temperatures, microhardness, cyclic fatigue, and torsional and bending strengths. Mood's median test was used for the statistical comparison with a significance set at 5%. The instruments were similar regarding the nickel/titanium ratio and overall design. Go-Taper Flex had the closest transformation temperatures to PTG. PTU and Go-Taper Flex had the highest microhardness (408.3 and 410.5 HVN). The time to fracture of Super Files Blue was three and seven times higher than PTG and PTU, respectively. No difference was observed in the maximum torque to fracture among PTG (1.30 N·cm) and the other systems, except for the Premium Taper Gold (1.05 N·cm) and Go-Taper Flex (1.10 N·cm). Significantly lower bending loads than PTG (269.2 gf) were observed for the EdgeTaper Platinum (158.3 gf) and Premium Taper Gold (103.5 gf) instruments. Super Files Blue outperformed PTG in the cyclic fatigue test, while EdgeTaper Platinum and Premium Taper Gold were more flexible. Premium Taper Gold and Go-Taper Flex showed lower torsional strength. Full article
(This article belongs to the Special Issue Advances and Applications of Nickel-Titanium Alloys in Medical Fields)
Show Figures

Figure 1

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Dear Colleagues,

Since the observation of shape memory characteristics in an almost equiatomic nickel-titanium (NiTi) alloy in research developed for the United States of America Navy, NiTi alloys have been employed not only in ocean engineering but also in medical fields, with applications in orthopedics, orthodontics, and endodontics. The almost equiatomic proportion of the main two elements leads to a weight proportion of around 56% nickel and 44% titanium. As with other metallic alloys, the NiTi alloy can exist in several crystallographic arrangements. The changes in the alloy arrangement may result from stress application or temperature effects. Due to their characteristics, NiTi alloys have been recurrently used in the manufacture of medical tools and instruments. This Special Issue intends to provide an overview of the latest advances, tendencies, and applications of this alloy in multiple areas of different medical fields. It is my pleasure to invite you to contribute to this Special Issue, where both research papers and reviews, with a focus on the following potential topics, are welcome. Potential topics include, but are not limited to: novel medical applications; advances in technical procedures; new technologies and recent developments in manufacturing; mechanical properties and novel modes to assess them; new concepts, and historical and future perspectives.

Dr. Jorge N.R. Martins
Guest Editor

{snippet name="submission_info"}

Back to TopTop