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Current and Future Trends in Orthodontic Materials

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

Deadline for manuscript submissions: closed (20 July 2022) | Viewed by 35966

Special Issue Editor

Department of Medical, Surgical and Health Sciences, University of Trieste, 34127 Trieste, Italy
Interests: growth indicators; functional treatment; skeletal anchorage; orthodontic materials; biomechanics

Special Issue Information

Dear Colleagues,

Orthodontic materials are significantly different from general dental materials. Orthodontics, indeed, can be considered a totally separate world in the universe of dentistry. The orthodontic community is a dynamic family which is always enthusiastic about the introduction of new orthodontic materials and new technologies or procedures.

Unfortunately, innovative materials are sometimes advertised and promoted without a solid scientific base. Literature on new materials is often produced only after the product’s commercialization, confirming or not a real innovation from a clinical perspective.

The latest trends in orthodontic materials are focused on aligners, miniscrews for orthodontic skeletal anchorage, orthodontic fixed materials as brackets and wires, and, finally, digital technology, such as 3D printings.

The aim of this Special Issue is to enrich the literature of quality studies regarding the more recent innovations around orthodontic materials and to provide a substantial contribution about the most promising procedures in the orthodontic discipline for the near future. Original articles, review articles, and preliminary studies are invited with particular interest in innovation in orthodontic sciences.

Prof. Luca Contardo
Guest Editor

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Keywords

  • aligners
  • skeletal anchorage
  • mechanical properties
  • superficial characteristics
  • orthodontic materials

Published Papers (12 papers)

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Research

Jump to: Review

10 pages, 2862 KiB  
Article
Friction Force Adjustment by an Innovative Covering System Applied with Superelastic NiTi Brackets and Wires—An In-Vitro Study
by Andrea Wichelhaus, Tena Eichenberg, Philip Gruber, Elias Panos Bamidis and Thomas Stocker
Materials 2022, 15(12), 4248; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15124248 - 15 Jun 2022
Viewed by 1397
Abstract
The aim of this study was the investigation of polymeric coverings to adjust frictional forces between V-shaped wires and brackets, both made of superelastic NiTi. Adjustment of frictional forces is relevant for certain stages during orthodontic therapy. Coverings able to generate frictional forces [...] Read more.
The aim of this study was the investigation of polymeric coverings to adjust frictional forces between V-shaped wires and brackets, both made of superelastic NiTi. Adjustment of frictional forces is relevant for certain stages during orthodontic therapy. Coverings able to generate frictional forces when assembled to such brackets are additively manufactured. Six different internal widths of coverings were examined in three different environments: dry condition at room temperature (RT) or body temperature (BT), or artificial saliva (AS) at RT. The different coverings significantly affected the frictional forces for all media (p < 0.001). A correlation between internal width of the covering and resulting frictional forces was found. BT and dry environment showed the lowest friction forces for all samples. The highest force was found for two covering types at RT in AS, while the remaining four covering types showed the highest values in dry environment (p < 0.001). Friction could, therefore, be adjusted by variation of bracket covering clipped onto brackets, which is useful for orthodontic therapy. Coverings delivering higher friction provide dental anchorage, while coverings with lower friction can be used for tooth movement or purely esthetic reasons. It was shown that the variation of covering width may be used for adjustment of frictional forces. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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11 pages, 1717 KiB  
Article
The Effects of Temperature and Time of Heat Treatment on Thermo-Mechanical Properties of Custom-Made NiTi Orthodontic Closed Coil Springs
by Thanate Assawakawintip, Peerapong Santiwong, Anak Khantachawana, Kawin Sipiyaruk and Rochaya Chintavalakorn
Materials 2022, 15(9), 3121; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15093121 - 26 Apr 2022
Cited by 10 | Viewed by 1791
Abstract
Nickel-Titanium (NiTi) springs have been increasingly used in orthodontics; however, no optimum condition of heat treatment has been reported. Therefore, this research was conducted to determine the optimum heat-treatment temperature and duration for the fabrication of NiTi-closed coil springs by investigating their effects [...] Read more.
Nickel-Titanium (NiTi) springs have been increasingly used in orthodontics; however, no optimum condition of heat treatment has been reported. Therefore, this research was conducted to determine the optimum heat-treatment temperature and duration for the fabrication of NiTi-closed coil springs by investigating their effects on thermo-mechanical properties. As-drawn straight NiTi wires of 0.2 mm diameter were used to fabricate closed coil springs of 0.9 mm lumen diameter. The springs were heat-treated at three different temperatures (400, 450, and 500 °C) with three different durations (20, 40, and 60 min). Electron Probe Micro-Analysis (EPMA) and Differential Scanning Calorimetry (DSC) were used to investigate element composition and thermo-mechanical properties, respectively. Custom-made NiTi closed coil springs composed of 49.41%-Ti and 50.57%-Ni by atomic weight, where their DSC curves of 500 °C presented the obvious endothermic and exothermic peaks, and the austenite finish temperature (Af) were approximately 25 °C. With increasing temperature, deactivation curves presented decreased plateau slopes generating higher superelastic ratios (SE ratios). At 500 °C, closed coil springs showed superelastic tendency with lower stress hysteresis. The thermo-mechanical properties were significantly influenced by heat-treatment temperature rather than duration. The optimum parameter appeared to be 500 °C for 40 min to produce appropriate force delivery levels, relatively low plateau slope, and lower hysteresis for orthodontic use. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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11 pages, 1287 KiB  
Article
Ion Release and Surface Changes of Nickel–Titanium Archwires Induced by Changes in the pH Value of the Saliva—Significance for Human Health Risk Assessment
by Zana Jusufi Osmani, Borut Poljšak, Saša Zelenika, Ervin Kamenar, Kristina Marković, Marko Perčić and Višnja Katić
Materials 2022, 15(6), 1994; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15061994 - 08 Mar 2022
Cited by 4 | Viewed by 1883
Abstract
The aim of this study was to explore whether changes in the salivary pH influence mechanical properties, surface roughness, and ion release from NiTi archwires with various surface coatings, and discuss the clinical significance of the findings. The uncoated, rhodium-coated, and nitrified NiTi [...] Read more.
The aim of this study was to explore whether changes in the salivary pH influence mechanical properties, surface roughness, and ion release from NiTi archwires with various surface coatings, and discuss the clinical significance of the findings. The uncoated, rhodium-coated, and nitrified NiTi wires were immersed into artificial saliva of different pH values (4.8, 5.1, 5.5, and 6.6). Released nickel and titanium ions were measured with inductively coupled plasma-optical emission spectroscopy at the end of 28 days. Atomic force microscopy was used to measure the arithmetic average surface roughness Ra, the root-mean-square roughness Rq, and the maximum height of the asperities RZ. The nanoindentation hardness (HIT) and Young’s modulus (EIT) measurements were performed. The change in the pH of artificial saliva is inversely proportional to the release of titanium from both coated and uncoated wires, and the release of nickel from uncoated wires. The surface roughness parameters of both coated and uncoated wires are unaffected by the change in the pH of artificial saliva. The change in the pH of saliva has minor influence on the hardness and Young’s modulus of elasticity of both coated and uncoated wires. The concentration of released metal ions measured was below the recommended upper limit for daily intake; nevertheless, hypersensitivity effects cannot be excluded, even at lower concentrations and at low pH. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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11 pages, 608 KiB  
Article
Bracket Bonding to All-Ceramic Materials with Universal Adhesives
by Cecilia Goracci, Giuseppe Di Bello, Lorenzo Franchi, Chris Louca, Jelena Juloski, Jovana Juloski and Alessandro Vichi
Materials 2022, 15(3), 1245; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15031245 - 08 Feb 2022
Cited by 3 | Viewed by 2019
Abstract
The need for bracket bonding to ceramic restorations is increasing. The aim of this study was to evaluate the effect of universal adhesives on bracket adhesion to polished or glazed lithium disilicate (LDS) and monolithic zirconia (MZ) surfaces. One hundred and twenty brackets [...] Read more.
The need for bracket bonding to ceramic restorations is increasing. The aim of this study was to evaluate the effect of universal adhesives on bracket adhesion to polished or glazed lithium disilicate (LDS) and monolithic zirconia (MZ) surfaces. One hundred and twenty brackets (N = 10) were bonded to either polished or glazed LDS (e.max CAD B32, Ivoclar Vivadent, Schaan, Liechtenstein) and MZ (In-Ceram® YZ, VITA, Bad Sackingen, Germany) blocks using three different adhesives combined with Transbond™ XT Paste (3M Unitek, Monrovia, CA, USA). Tested universal adhesives were Scotchbond™ Universal Adhesive (SU, 3M St. Paul, MN, USA) and Assure Plus (AP, Reliance, Itasca, IL, USA). Transbond™ XT Primer (XTP, 3M Unitek, Monrovia, CA, USA) served as a control adhesive. Bracket bond strength was measured in shear mode (SBS). Failure type was determined by the Modified Adhesive Remnant Index (ARI). Data were statistically analyzed. On polished LDS, SU yielded bracket SBS significantly superior to those of AP and XTP. On polished MZ, the use of SU and AP significantly enhanced bracket retention as compared with XTP. Low SBS values, below the threshold of clinical acceptability, were reached by all tested adhesives on glazed LDS and MZ specimens. SBS measurements corresponded with failure type observations. Universal adhesives SU and AP could be considered for use on polished LDS and MZ surfaces. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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15 pages, 1032 KiB  
Article
Orthodontic Retention—Protocols and Materials—A Questionnaire Pilot Study among Polish Practitioners
by Maciej Jedliński, Marta Mazur, Krzysztof Schmeidl, Katarzyna Grocholewicz, Roman Ardan and Joanna Janiszewska-Olszowska
Materials 2022, 15(2), 666; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15020666 - 16 Jan 2022
Cited by 5 | Viewed by 2308
Abstract
The aim of the study was to analyze retention protocols and materials for fixed retainers used by clinicians providing orthodontic treatment in Poland. The survey was carried out from February to April 2021. The questionnaire was designed using the Google Forms tool. After [...] Read more.
The aim of the study was to analyze retention protocols and materials for fixed retainers used by clinicians providing orthodontic treatment in Poland. The survey was carried out from February to April 2021. The questionnaire was designed using the Google Forms tool. After validation, the questionnaire was delivered to verified active orthodontists gathered in a closed social media group of 615 members. Finally, 104 answers were received. Answers to individual questions were provided in percentages and tabularized. A chi-squared test of proportion was used to compare: the proportion of clinicians using retainers of different characteristics and the proportions of clinicians indicating the superiority of a given clinical solution. Rectangular steel braided wire was rated as most reliable. However, doctors who declared to use gold chain were mostly solely using this type of wire. Multistranded round wire was rated the worst. Fiber-reinforced composite was mainly used in periodontal patients. The protocols used by Polish orthodontic practitioners relied on double long-term retention with regular follow-up. The most popular material was stainless steel braided rectangular wire bonded with a flowable composite. Most clinicians believed they could maintain the treatment results, but they declared that patients’ cooperation was a challenge. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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10 pages, 1411 KiB  
Article
Effect of Water-Based Disinfectants or Air-Drying on Dimensional Changes in a Thermoplastic Orthodontic Aligner
by Davide Bresolato, Andrea Volpato, Lorenzo Favero and Riccardo Favero
Materials 2021, 14(24), 7850; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14247850 - 18 Dec 2021
Viewed by 1769
Abstract
The polymer structure of thermoplastic materials currently used to make aligners is altered by the oral conditions and this negatively affects their capacity to move teeth. This study aimed to compare different options for storing aligners when not in use by superimposing successive [...] Read more.
The polymer structure of thermoplastic materials currently used to make aligners is altered by the oral conditions and this negatively affects their capacity to move teeth. This study aimed to compare different options for storing aligners when not in use by superimposing successive 3D images to identify which storage method least affects material shape and weight. Fifty PET-G aligners, produced using the CA Digital method, were divided into four groups (1A, 1B, 1C, and 2D) and were stored for 18 h a day in artificial saliva at 37 °C. Then, to mimic their storage conditions when not in use, aligners in group 1A were immersed for the remaining 8 hours a day in bicarbonate solution, those in group 1B in chlorhexidine solution, those in group 1C in distilled water, and those in group 2D were stored dry. The samples were scanned at the baseline (before the immersion cycles began) and again two weeks later. The digital scans were superimposed and the median deformation, its variability, and weight differences were recorded for each group. Statistical analysis showed aligner deformation (expansion) in all three groups stored in wet conditions, with a statistically significant difference between groups 1A and 1C. Aligners in group 2D shrank slightly, and to a significantly greater degree with respect to group 1C. Variability in the degree of deformation was similar among the three groups stored in wet conditions, but significantly greater in group 2D. Weight gains were recorded in all four groups, the smallest in group 2D and the largest in group 1A. Storing aligners in dry conditions promoted lower deformation in the material, involving a slight shrinkage, whereas wet storage conditions caused an expansion of the aligner, especially when distilled water is used. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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18 pages, 1608 KiB  
Article
The Effect of Brilliant Blue-Based Plaque-Staining Agents on Aesthetic Orthodontic Appliances
by Justyna Topolska, Sylwia Motyl, Aleksandra Orłowska, Andrzej Borkowski, Paweł Działak and Krzysztof Gronkiewicz
Materials 2021, 14(22), 7050; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14227050 - 20 Nov 2021
Cited by 1 | Viewed by 1470
Abstract
Orthodontic appliances discolour over treatment time, and a yellowish plaque builds up on the contact area of the brackets, adhesive and teeth. Brilliant Blue-based plaque-staining agents (BBPSAs), which increase tooth brushing efficiency, have the potential to support the maintenance of proper oral hygiene [...] Read more.
Orthodontic appliances discolour over treatment time, and a yellowish plaque builds up on the contact area of the brackets, adhesive and teeth. Brilliant Blue-based plaque-staining agents (BBPSAs), which increase tooth brushing efficiency, have the potential to support the maintenance of proper oral hygiene during orthodontic treatment. However, they exhibit strong colouring properties, and their impact on the aesthetics of braces remains unclear. Therefore, the aim of this study was to investigate the influence of commercially available BBPSAs on the colour of aesthetic orthodontic materials. A light-cured, colour-changing orthodontic adhesive and new-generation, monocrystalline, sapphire brackets were chosen for the experiments. The effect of the staining agent on the tested materials was investigated in terms of the reaction temperature and time, as well as the presence of black tea-induced impurities on the materials. The CIELAB (Commission Internationale de L’éclairage L* a* b*) colour system parameters were measured, and the colour differences (ΔE*ab and ΔE00—the Commission Internationale de L’éclairage 2000 colour-difference) were determined for the materials under several experimental conditions. The braces’ green-red colour expression was positively affected by the BBPSA. Under in vitro conditions, the regular use of the BBPSA for 90 days visibly improved the unfavourable colour change caused by the black tea. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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10 pages, 2171 KiB  
Article
Effect of Microimplant Neck Design with and without Microthread on Pullout Strength and Destruction Volume
by Yu-Chuan Tseng, Han-Sheng Chen, Szu-Yu Hsiao, Kun-Jung Hsu and Chun-Ming Chen
Materials 2021, 14(20), 5991; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14205991 - 12 Oct 2021
Viewed by 1279
Abstract
The microthread neck concept has been applied to dental implants. This study investigated the pullout strength and destruction volume of orthodontic microimplants with and without the microthread neck design. Fifteen microimplants (diameter: 1.5 × 10 mm) of three types (Types A and B: [...] Read more.
The microthread neck concept has been applied to dental implants. This study investigated the pullout strength and destruction volume of orthodontic microimplants with and without the microthread neck design. Fifteen microimplants (diameter: 1.5 × 10 mm) of three types (Types A and B: without microimplant neck; Type C: with microimplant neck) were tested. The insertion torque (IT), Periotest value (PTV), horizontal pullout strength (HPS), and horizontal destruction volume (HDV) of each type were measured. Kruskal–Wallis H test and Dunn’s post-hoc comparison test were performed to compare the measured values of the three types of microimplants. The correlations of the measured values were used to perform the Spearman’s correlation coefficient analysis. The ITs of Types B (8.8 Ncm) and C (8.9 Ncm) were significantly higher than those of Type A (5.2 Ncm). Type B yielded the lowest PTV (4.1), and no statistical differences in PTV were observed among the three types. Type A had a significantly lower HPS (158.8 Ncm) than Types B (226.9 Ncm) and C (212.8 Ncm). The three types did not exhibit any significant differences in the HDV. The results of the Spearman’s correlation coefficient test revealed that HDV (ρ = 0.710) and IT (ρ = 0.813) were strongly correlated with HPS, whereas for PTV and HPS, it was not. HPS was strongly and significantly correlated with HDV. The orthodontic microimplant with a microimplant neck design did not perform better than that without a microthread in the mechanical strength test. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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13 pages, 1773 KiB  
Article
Vertical and Orovestibular Forces Generated by Beta-Titanium and Stainless-Steel Rectangular Wires in Labial and Fully Customized Lingual Bracket Systems
by Chrystalla Kyprianou, Athina Chatzigianni, Nikolaos Daratsianos and Christoph Bourauel
Materials 2021, 14(19), 5632; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14195632 - 28 Sep 2021
Cited by 2 | Viewed by 1737
Abstract
This study aimed to investigate the force values exerted from rectangular wires when combined with conventional labial and fully customized lingual appliances under predefined, idealized activation. Fully customized lingual brackets of two brands Incognito™ (3M Unitek, Monrovia, CA, USA) and WIN (DW Lingual [...] Read more.
This study aimed to investigate the force values exerted from rectangular wires when combined with conventional labial and fully customized lingual appliances under predefined, idealized activation. Fully customized lingual brackets of two brands Incognito™ (3M Unitek, Monrovia, CA, USA) and WIN (DW Lingual Systems, Bad Essen, Germany) and labial brackets of another brand, discovery® MIM and discovery® smart systems (Dentaurum, Ispringen, Germany), were chosen. Stainless-steel and beta-titanium wires of 0.018” × 0.025” were examined. For IncognitoTM, 0.0182” × 0.025” beta-titanium wires were tested. Intrusion/extrusion and orovestibular movements were performed in a range of 0.2 mm, and the forces were recorded for each 0.1 mm of the movement. Mean values and standard deviations were calculated for all measurements, and ANOVA was performed for statistical analysis. Slight differences were observed between the forces generated from beta-titanium and stainless-steel wires. The same wire generated in some cases 5–53% higher forces with the lingual appliance due to the vertical orientation of the long walls during intrusion/extrusion and increased wire stiffness at the anterior region. Beta-titanium and stainless-steel 0.018” × 0.025” wires can generate similar force values during the final stages of the orthodontic therapy; thus, possibly only one of the two alloys could be used in each orthodontic wire sequence. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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12 pages, 2463 KiB  
Article
Bacterial Exposure to Nickel: Influence on Adhesion and Biofilm Formation on Orthodontic Archwires and Sensitivity to Antimicrobial Agents
by Andrej Pavlic, Gabrijela Begic, Marin Tota, Maja Abram, Stjepan Spalj and Ivana Gobin
Materials 2021, 14(16), 4603; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14164603 - 16 Aug 2021
Cited by 4 | Viewed by 1875
Abstract
The presence of nickel could modify bacterial behavior and susceptibility to antimicrobial agents. Adhesion and biofilm formation on orthodontic archwires can be a source of bacterial colonization and possible health hazards. Staphylococcus aureus was subjected to exposure and adaptation to various sub-inhibitory concentrations [...] Read more.
The presence of nickel could modify bacterial behavior and susceptibility to antimicrobial agents. Adhesion and biofilm formation on orthodontic archwires can be a source of bacterial colonization and possible health hazards. Staphylococcus aureus was subjected to exposure and adaptation to various sub-inhibitory concentrations of nickel. Five strains of bacteria adapted to nickel in concentrations of 62.5–1000 μg/mL were tested for adhesion and biofilm formation on nickel-titanium archwires. Archwires were previously incubated in artificial saliva. Bacteria were incubated with orthodontic wire with stirring for 4 h (adhesion) and 24 h (biofilm formation). The number of adherent bacteria was determined after sonication and cultivation on the Muller-Hinton agar. Disk diffusion method was performed on all bacteria to assess the differences in antimicrobial susceptibility. Bacteria adapted to lower concentrations of nickel adhered better to nickel-titanium than strains adapted to higher concentrations of nickel (p < 0.05). Biofilm formation was highest in strains adapted to 250 and 500 μg/mL of nickel (p < 0.05). The highest biofilm biomass was measured for strains adapted to 250 μg/mL, followed by those adapted to 1000 μg/mL. Bacteria adapted to lower concentrations of nickel demonstrated lower inhibition zone diameters in the disk diffusion method (p < 0.05), indicating increased antimicrobial resistance. In conclusion, bacteria adapted to 250 μg/mL of nickel ions adhered better, demonstrated higher biofilm formation and often had higher antimicrobial resistance than other adapted and non-adapted strains. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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Review

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18 pages, 2215 KiB  
Review
A Critical Appraisal of the Use and Properties of Nickel–Titanium Dental Alloys
by Petra Močnik and Tadeja Kosec
Materials 2021, 14(24), 7859; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14247859 - 18 Dec 2021
Cited by 14 | Viewed by 3273
Abstract
Nickel–titanium (NiTi) archwires are used in dentistry for orthodontic treatment. NiTi alloys have favourable mechanical characteristics, such as superelasticity and shape memory, and are also known as a corrosion-resistant alloy. In specific cases, an archwire could be attacked by certain types of corrosion [...] Read more.
Nickel–titanium (NiTi) archwires are used in dentistry for orthodontic treatment. NiTi alloys have favourable mechanical characteristics, such as superelasticity and shape memory, and are also known as a corrosion-resistant alloy. In specific cases, an archwire could be attacked by certain types of corrosion or wear degradation, which can cause the leaching of metal ions and a hypersensitive response due to increased concentrations of Ni in the human body. A systematic search of the literature retrieved 102 relevant studies. The review paper focuses on three main fields: (i) electrochemical properties of NiTi wires and the effect of different environments on the properties of NiTi wires (fluoride and low pH); (ii) tribocorrosion, a combination of chemical and mechanical wear of the material, and (iii) the biocompatibility of NiTi alloy and its subsequent effect on the human body. The review showed that corrosion properties are affected by microstructure, pH of saliva and the presence of fluorides. A high variation in published results should be, therefore, interpreted with care. The release of nickel ions was assessed using the same unit, showing that the vast majority of metal ions were released in the first few days of exposure, then a stable, steady state was reached. In tribocorrosion studies, the increased concentrations of Ni ions were reported. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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11 pages, 1250 KiB  
Review
Direct 3D Printing of Clear Orthodontic Aligners: Current State and Future Possibilities
by Gianluca M. Tartaglia, Andrea Mapelli, Cinzia Maspero, Tommaso Santaniello, Marco Serafin, Marco Farronato and Alberto Caprioglio
Materials 2021, 14(7), 1799; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14071799 - 05 Apr 2021
Cited by 82 | Viewed by 12333
Abstract
The recent introduction of three-dimensional (3D) printing is revolutionizing dentistry and is even being applied to orthodontic treatment of malocclusion. Clear, personalized, removable aligners are a suitable alternative to conventional orthodontic appliances, offering a more comfortable and efficient solution for patients. Including improved [...] Read more.
The recent introduction of three-dimensional (3D) printing is revolutionizing dentistry and is even being applied to orthodontic treatment of malocclusion. Clear, personalized, removable aligners are a suitable alternative to conventional orthodontic appliances, offering a more comfortable and efficient solution for patients. Including improved oral hygiene and aesthetics during treatment. Contemporarily, clear aligners are produced by a thermoforming process using various types of thermoplastic materials. The thermoforming procedure alters the properties of the material, and the intraoral environment further modifies the properties of a clear aligner, affecting overall performance of the material. Direct 3D printing offers the creation of highly precise clear aligners with soft edges, digitally designed and identically reproduced for an entire set of treatment aligners; offering a better fit, higher efficacy, and reproducibility. Despite the known benefits of 3D printing and the popularity of its dental applications, very limited technical and clinical data are available in the literature about directly printed clear aligners. The present article discusses the advantages of 3D printed aligners in comparison to thermoformed ones, describes the current state of the art, including a discussion of the possible road blocks that exist such as a current lack of approved and marketed materials and limited existence of aligner specific software. The present review suggests the suitability of 3D direct printed aligners is superior to that of thermoformed manufactured aligners because of the prior’s increased accuracy, load resistance, and lower deformation. It is an overall more stable way to produce an aligner where submillimeter movements can make a difference in treatment outcome. Direct 3D printing represents a complex method to control the thickness of the aligner and therefore has a better ability to control the force vectors that are used to produce tooth movement. There is currently no other approved material on the market that can do this. The conclusion of this article is that we encourage further in vitro and in vivo studies to test these new technologies and materials. Full article
(This article belongs to the Special Issue Current and Future Trends in Orthodontic Materials)
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