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Journal of Orofacial Orthopedics =... Mar 2019Mechanical properties along the length of latest generation "multi-force" archwires were measured and compare with commercially available thermally activated and... (Comparative Study)
Comparative Study
AIMS
Mechanical properties along the length of latest generation "multi-force" archwires were measured and compare with commercially available thermally activated and non-thermally activated nickel-titanium (NiTi) archwires.
MATERIALS AND METHODS
A modified deflection test was used to produce load/deflection curves for different positions along the lengths of a sample of 114 NiTi archwires composed by thermal NiTi, non-thermal NiTi, two types of multi-force NiTi and one type of multi-force copper archwires of various cross-sections (0.016 × 0.016 inch, 0.016 × 0.022 inch, 0.018 × 0.025 inch and 0.019 × 0.025 inch). The length, slope and mean force expressed were calculated from the resulting unloading plateaus, enabling comparison between types of archwire at different points along their lengths.
RESULTS
Among conventional thermal, conventional nonthermal and multiforce archwires, all parameters investigated were statistically different, whereby the performance of the latter was superior. Multi-force archwires displayed 27% and 31% lighter mean forces in the upper and lower arches, respectively, in addition to 62% and 40% reductions in unloading plateau slope and length, respectively, as compared to conventional CuNiTi wires. Comparison of the different types of multi-force wires tested revealed statistically significant differences in the three parameters, depending on the testing position but irrespective of their cross-section.
CONCLUSIONS
Although conventional archwires display identical behaviour along their lengths, as advertised the multi-force archwires do indeed exert a progressive force which differs between anterior, medial and posterior sections. The multi-force wires provide lighter, more prolonged and constant forces than conventional wires without cross-section-dependent variation.
Topics: Alloys; Dental Stress Analysis; Orthodontic Wires; Stress, Mechanical; Weight-Bearing
PubMed: 30610250
DOI: 10.1007/s00056-018-00164-4 -
Orthodontics & Craniofacial Research Feb 2021The objective of this study was to compare the resistance to sliding of aesthetic orthodontic coated wires after prolonged water immersion for up to 4 weeks.
OBJECTIVE
The objective of this study was to compare the resistance to sliding of aesthetic orthodontic coated wires after prolonged water immersion for up to 4 weeks.
SETTING AND SAMPLE POPULATION
An in vitro study of commercially available orthodontic appliances.
MATERIALS AND METHODS
Aesthetic coated stainless-steel wires (Parylene-coated, epoxy-coated and Teflon-coated) (0.019" × 0.025") and an uncoated control were immersed in distilled-deionized water for zero, two or four weeks at 37°C and then were subjected to resistance-to-sliding tests through a three-bracket system of sapphire ceramic brackets (0.022" × 0.028" slot) and clear-coloured elastic ligatures at a contact angle of 0° or 3°. Maximal and average resistance to sliding was analysed by a three-way analysis of variance, two general linear models and a post hoc Tukey's honest significant difference test.
RESULTS
Water immersion time, contact angle, wire group and their interactions had statistically significant effects on the resistance to sliding of tested orthodontic wires. Various coated wires had distinct timely changes in the maximal and average resistance to sliding after water immersion for 2 to 4 weeks. When compared to the uncoated control in most of the experimental conditions, epoxy-coated wires had lower or non-significant differences in resistance to sliding, while Parylene-coated wire had higher resistances.
CONCLUSIONS
Prolonged water immersion for weeks alters the resistance to sliding of aesthetic orthodontic wires coated with Parylene, epoxy or Teflon. Based on their resistance to sliding, different designs in orthodontic biomechanics should be considered for the different aesthetic orthodontic coated wires.
Topics: Dental Alloys; Esthetics, Dental; Friction; Immersion; Materials Testing; Nickel; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Stainless Steel; Surface Properties; Titanium; Water
PubMed: 32741117
DOI: 10.1111/ocr.12413 -
Journal of the Mechanical Behavior of... Feb 2021Orthodontic archwire rotation around its long axis, known as third-order torque, is utilised to correct tooth rotational misalignments moving the tooth root closer to or...
Orthodontic archwire rotation around its long axis, known as third-order torque, is utilised to correct tooth rotational misalignments moving the tooth root closer to or away from the cheek through engagement with an orthodontic bracket. Studying the behaviour of archwire and brackets during an applied rotation can aid in better understanding and appreciating the mechanics of third-order torque, potentially allowing for more effective orthodontic treatment protocols. Mechanically characterising archwire behaviour during third-order torque application is a complex task due to their physical scale and geometries. An advanced measurement technique was needed to address these constraints. A three-dimensional (3D) non-contact optical method using a digital image correlation (DIC) system was developed. An orthodontic torque simulator (OTS) was used to apply and measure third-order torque with 0.483 × 0.635 mm (0.019″ x 0.025″) rectangular archwires in tandem with a 3D DIC system, whereby surface deformations and strains could be computed using correlation algorithms. The 3D DIC system was implemented to enable third-order torque experimentation with the OTS while imaging the archwire and bracket surfaces. The 3D DIC system's ability to measure 3D archwire deformations and strains was verified using a finite element model, where comparisons between 3D DIC measurements and calculated results from the model were made to ensure the measurement capabilities of 3D DIC in the context of third-order torque. The 3D DIC system was then used to compare archwire behaviour between stainless steel (SS) and titanium molybdenum alloy (TMA) archwires to study potential clinical differences in archwire behaviour, in which the archwires were rotated with a custom SS rigid dowel (RD) as well as commercial Damon Q orthodontic brackets. The quantification of third-order torque and archwire deformations and strains led to the conclusion that SS archwires led to larger torque magnitudes compared to TMA archwires. The RD resulted in larger archwire strains compared to Damon Q brackets. The 3D DIC system provides a non-contact measurement technique that can further be used with third-order torque experimentation with the OTS.
Topics: Dental Alloys; Dental Stress Analysis; Materials Testing; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Stainless Steel; Surface Properties; Titanium; Torque
PubMed: 33221162
DOI: 10.1016/j.jmbbm.2020.104196 -
Head & Face Medicine Nov 2020The Multiloop Edgewise Archwire (MEAW) appliance is an orthodontic treatment method suitable for the therapy of severe types of malocclusions such as open bites or... (Review)
Review
BACKGROUND
The Multiloop Edgewise Archwire (MEAW) appliance is an orthodontic treatment method suitable for the therapy of severe types of malocclusions such as open bites or anterior crossbites. The cephalometric Denture Frame Analysis (DFA) provides a supportive diagnostic tool for patient-specific treatment planning concerning the rearrangement of occlusion within the "denture frame". The objective of this study is to give a comprehensive overview of the national and international scientific literature about MEAW and DFA regarding the general therapeutic effects, advantages and limitations.
METHODS AND MATERIALS
A computerized literature search was performed using four principal medical databases (PubMed/Medline, Google Scholar, Web of Science and Cochrane Central Register of Controlled Trials) and supplemented by manual searching of the references listed in the retrieved articles. The results were screened and assessed following the PRISMA guidelines.
RESULTS
Six hundred seventy-seven full articles were assessed for eligibility. A number of 134 articles went through qualitative analysis and 3 studies were finally involved in comparative synopsis. The findings reveal advantageous characteristics of the MEAW technique such as a high degree of three-dimensional individual tooth control and a comparatively low load deflection rate, causing mostly dentoalveolar changes without significantly influencing the skeletal structures.
CONCLUSION
Based on current literature, the MEAW technique appears to have several therapeutic benefits and serves as a sufficient alternative treatment method for dentoalveolar compensation, when measures of orthognathic surgery are rejected. Concerning the deficient data basis of available literature and the low level of scientific evidence, further studies are required in order to expand on the knowledge in this subject area. Several aspects like the effectiveness or the long-term stability have to be evaluated more extensively. Moreover, the transferability of the DFA to ethnic groups other than the Asian ethnicity should be examined further.
Topics: Cephalometry; Dentures; Humans; Malocclusion; Orthodontic Wires; Tooth Movement Techniques
PubMed: 33243257
DOI: 10.1186/s13005-020-00247-x -
Journal of Orofacial Orthopedics =... Sep 2018This study aimed to determine and compare the mechanical properties of novel CAD/CAM(computer-aided design/manufacturing)-individualized nickel-titanium (NiTi) and...
PURPOSE
This study aimed to determine and compare the mechanical properties of novel CAD/CAM(computer-aided design/manufacturing)-individualized nickel-titanium (NiTi) and conventional twisted wires.
METHODS
Seven NiTi wires (angular, 0.20 × 0.20 mm up to 0.50 × 0.50 mm) and two twisted steel wires (round, 0.40 mm and 0.44 mm) were investigated in three-point (3PBT) and four-point bending tests (4PBT) using the Orthodontic Measurement and Simulation System. All wires were loaded up to a distance of 3.3 mm, and resulting forces were measured. Additionally, in the biomechanical test (BMT), CAD/CAM-individualized NiTi retainers (0.35 × 0.35 mm) were subjected to intrusive and extrusive deformation of 0.1, 0.2, and 0.4 mm.
RESULTS
For twisted wires, typical plastic deformations were found in 3PBT (0.40 mm: 0.3 mm; 0.44 mm: 0.4 mm), and maximum resulting forces for these reached 1.3 N and 3.2 N for the 0.40 mm and 0.44 mm wires, respectively. Corresponding values in the 4PBT totaled 0.8 N for the 0.40 mm and 1.9 N for the 0.44 mm twisted wire. The NiTi samples showed plastic deformations in the 3PBT for the 0.25 × 0.25 mm dimension and in 4PBT for the 0.35 mm × 0.35 mm version. At a deflection of 1.5 mm, both tests revealed significantly different forces for the NiTi wires of different dimensions (p ≤ 0.001). In the BMT, no remarkable loading plateau or plastic deformation was observed. The resulting forces were significantly higher for extrusive than for intrusive deformation (p ≤ 0.001).
CONCLUSIONS
Individualized NiTi retainers feature specific elasticity and dimensional stability, and more deflection is necessary to achieve permanent deformations. The CAD/CAM production process did not significantly influence the biomechanical properties of the NiTi wires.
Topics: Alloys; Biomechanical Phenomena; Computer-Aided Design; Dental Stress Analysis; Elasticity; In Vitro Techniques; Materials Testing; Orthodontic Retainers; Orthodontic Wires; Surface Properties
PubMed: 30014179
DOI: 10.1007/s00056-018-0144-2 -
BMC Oral Health Jun 2023Controlling the 3D movement of central incisors during tooth extraction cases with clear aligners is important but challenging in invisible orthodontic treatment. This...
BACKGROUND
Controlling the 3D movement of central incisors during tooth extraction cases with clear aligners is important but challenging in invisible orthodontic treatment. This study aimed to explore the biomechanical effects of central incisors in tooth extraction cases with clear aligners under different power ridge design schemes and propose appropriate advice for orthodontic clinic.
METHODS
A series of Finite Element models was constructed to simulate anterior teeth retraction or no retraction with different power ridge designs. These models all consisted of maxillary dentition with extracted first premolars, alveolar bone, periodontal ligaments and clear aligner. And the biomechanical effects were analysed and compared in each model.
RESULTS
For the model of anterior teeth retraction without power ridge and for the model of anterior teeth no retraction with a single power ridge, the central incisors exhibited crown lingual inclination and relative extrusion. For the model of anterior teeth no retraction with double power ridges, the central incisors tended to have crown labial inclination and relative intrusion. For the model of anterior tooth retraction with double power ridges, the central incisors exhibited a similar trend to the first kind of model, but as the depth of the power ridge increased, there was a gradual decrease in crown retraction value and an increase in crown extrusion value. The simulated results showed that von-Mises stress concentration was observed in the cervical and apical regions of the periodontal ligaments of the central incisors. The clear aligner connection areas of adjacent teeth and power ridge areas also exhibited von-Mises stress concentration and the addition of power ridge caused the clear aligner to spread out on the labial and lingual sides.
CONCLUSIONS
The central incisors are prone to losing torque and extruding in tooth extraction cases. Double power ridges have a certain root torque effect when there are no auxiliary designs, but they still cannot rescue tooth inclination during tooth retraction period. For tooth translation, it may be a better clinical procedure to change the one-step aligner design to two-step process: tilting retraction and root control.
Topics: Humans; Incisor; Orthodontic Wires; Cuspid; Maxilla; Tooth Extraction; Orthodontic Appliances, Removable; Tooth Movement Techniques; Finite Element Analysis
PubMed: 37349701
DOI: 10.1186/s12903-023-03106-8 -
Journal of the College of Physicians... Mar 2018Orthodontic alignment of un-erupted dilacerated teeth is challenging, as the bent roots resist forces applied to move them through the bone. Various treatment options...
Orthodontic alignment of un-erupted dilacerated teeth is challenging, as the bent roots resist forces applied to move them through the bone. Various treatment options are now available to treat this condition including providing prosthesis after extractions and apicectomies. However, to maintain alveolar bone in the area of the un-erupted tooth, especially if the involved tooth is in the anterior segment, the ideal treatment would be to try and bring the tooth in the arch orthodontically. Treatment requires increased time duration, compliance of the patient, and consistent force mechanics. This case report is of a 9-year boy with un-erupted and dilacerated teeth. Orthodontic treatment of prolonged duration was provided to bring these teeth into the arch, improving the esthetics and function.
Topics: Child; Dental Arch; Humans; Male; Malocclusion; Orthodontic Brackets; Orthodontic Wires; Tooth, Impacted; Tooth, Unerupted; Treatment Outcome
PubMed: 29544588
DOI: 10.29271/jcpsp.2018.03.245 -
Dental Materials Journal Mar 2018Titanium nitride (TiN) coating by ion plating has properties such as high hardness, wear resistance, corrosion resistance, and surface lubricity, therefore TiN coating...
Titanium nitride (TiN) coating by ion plating has properties such as high hardness, wear resistance, corrosion resistance, and surface lubricity, therefore TiN coating is often used in various dental appliances and materials. In this study, we evaluated the corrosion behaviors and mechanical properties of TiN coated stainless steel (SS) and nickel titanium (Ni-Ti) orthodontic wires prepared by ion plating. TiN coating by ion plating improves the corrosion resistance of orthodontic wires. The corrosion pitting of the TiN coated wire surface become small. The tensile strength and stiffness of SS wire were increased after TiN coating. In contrast, its elastic force, which is a property for Ni-Ti wire, was decreased. In addition, TiN coating provided small friction forces. The low level of friction may increase tooth movement efficiently. Therefore, TiN coated SS wire could be useful for orthodontics treatment.
Topics: Coated Materials, Biocompatible; Corrosion; Dental Alloys; Electroplating; Hardness; Materials Testing; Nickel; Orthodontic Wires; Stainless Steel; Surface Properties; Tensile Strength; Titanium
PubMed: 29109336
DOI: 10.4012/dmj.2016-348 -
Scientific Reports Jun 2022This observational study evaluates three-dimensionally the relation between the root of maxillary canine and overlying labial cortical plate of bone during orthodontic... (Observational Study)
Observational Study
This observational study evaluates three-dimensionally the relation between the root of maxillary canine and overlying labial cortical plate of bone during orthodontic canine retraction. Eighty-four bilateral maxillary canines in 42 patients were retracted in the extraction space of first premolars, using conventional orthodontic NiTi retraction spring delivering 150gm. Three-dimensional evaluation at the cusp tip, root apex, and the overlying cortical bone was done based on Classification of Root/Cortical bone relation (CRCR) before and after canine retraction. 168 observations of the canines pre- and post-retraction showed a mean distal movement of the canine cusp tip of 3.78(± 2.05) mm, while the canine root apex was almost stationary. Scarcely, 5.4% of the canine roots and root apices persisted in the medullary bone during retraction, while 16.1% contacted the overlying cortical bone. Fenestration of the overlying cortical bone by the canine roots or root apices occurred in 78.6% of the sample. The unembellished intimacy between the canine root and apex to the overlying thick dense cortical bone might have the decelerating effect on the maxillary canine retraction. The natural bone plate labial to the maxillary canine root did not yield infront nor enlarge due to canine retraction, but else defeated the current orthodontic biomechanical implementation.
Topics: Cortical Bone; Cuspid; Humans; Maxilla; Orthodontic Wires; Tooth Movement Techniques
PubMed: 35739156
DOI: 10.1038/s41598-022-14663-3 -
The Angle Orthodontist Sep 2021To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb])...
OBJECTIVES
To examine the torque moment that occurs between esthetic brackets and bendable alloy (stainless steel [SS], titanium-molybdenum [Ti-Mo], and titanium-niobium [Ti-Nb]) wires.
MATERIALS AND METHODS
This study examined ceramic (CR), zirconium oxide (ZC), polycarbonate (PC), and conventional metallic brackets (MT) (upper, 0.018-inch and 0.022-inch slots) combined with SS, Ti-Mo, and Ti-Nb wires using elastic module ligation. The torque moments delivered by various wire and bracket combinations were measured using a torque gauge apparatus. The wire torque angles at 5-40° were examined.
RESULTS
The torque value increased in the order of CR, ZC, MT, and PC brackets for both 0.018-inch and 0.022-inch slots. The fracture points of the CR and ZC brackets combined with SS and Ti-Mo wires were approximately more than 30° and 35°, respectively. No fracture points were detected in the combination of ZC brackets and Ti-Nb wires.
CONCLUSIONS
The current study identified the material characteristics of CR, ZR, and PC brackets during torque tooth movements. The present results demonstrate a characteristic combined effect between different esthetic brackets and bendable alloy wires.
Topics: Alloys; Dental Stress Analysis; Esthetics, Dental; Materials Testing; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Stainless Steel; Titanium; Torque
PubMed: 33822872
DOI: 10.2319/081820-729.1