Archwire Research Articles

Experimental studies for the progressive assessment of stress distributions on orthodontic archwire.

This paper presents experimental studies to examine effect of crowding stages on stress distributions on orthodontic archwire using loading tests and 2D photogrammetry technique. Three specimens representing crowding II, crowding I, and alignment stage were fabricated based on a 3D images of upper teeth. Engaged NiTi archwire is loaded with weights to induce deformation, and 2D photogrammetry technique was used to loaded wire and curvature change of the engaged wire from the captured images. Axial and flexural stresses were obtained, which were used to calculate von Mises stress distributions along the wire. The results show that the averaged von Mises stress of archwire was released in about 10% when the alignment of teeth changes from crowding II to I and crowding I to alignment. Comparing all three stages, it was common that flexural stresses were much larger than the axial stresses. In addition, the wire stresses were concentrated more on molar teeth area due to anchorage effect, regardless of crowding stage. This study shows not only how stresses were distributed along the wire but also how stress distributions on wire change as orthodontic treatment proceeded, which can be used to improve effectiveness of treatment and develop wire design.

Analytical study for prediction of stress distribution on orthodontic archwire considering short-term stress loss

This article proposes a method to predict the stress distributions on orthodontic archwires by considering the short-term stress losses. First, finite element (FE) analysis and numerical analysis using stress-loss formulations were performed. The FE models of the upper teeth and archwire were generated, and the initial stresses along the archwire were predicted from the FE model. The initial stresses on the wire were released in a relatively short amount of time due to shortening of the teeth, and slip and friction between the wire and brackets. Therefore, the formulations for the short-term stress losses were adopted from prestressed concrete design techniques and used to calculate the wire stress releases. To validate, loading tests and image processing were conducted, and the stresses were calculated from the deformations and curvatures of the loaded wire images. FE analyses without considering the stress losses predicted the stress distributions are unrealistically large; hence, including losses from elastic shortening, anchorage slip, and friction area could reduce the initial stresses by 16–34%. Comparing the average wire stress from FE analysis with image processing, a difference of only 0.82% was noted, which validates the method for predicting stress distribution using FE analysis and the method for stress loss calculations.

Orthodontic Bracket Friction Affected by Design Selection Material and Manufacturing Process

One of the problems in orthodontic treatment is friction. Some of the factors that support friction are archwire material, archwire dimensions, bracket material, surface roughness, type of ligation, environmental humidity, and bracket position, angulation angle between bracket and wire, changes in the surface of the archwire and bracket. The aim of this study is to analyse the difference in friction between the two branded bracket designs and a new patented bracket (patent no. IDP000069597). The production method for this new bracket is different, however, uses the same material of 17-4 PH stainless steel. There are three groups in this research, one sample of bracket each from two different branded and one sample of a new bracket design. All three groups were tested for microstructure, then tested for measurement of friction between bracket slots and archwire. The microstructure of the two branded brackets has a martensitic phase that is not as dense as the new bracket, which is due to the different manufacturing method processes. The two branded brackets use the metal injection molding method, while the new brackets use the investment casting method. The friction test results show that there are significant differences between the three groups of brackets. One of the branded brackets (A) has the lowest friction, but branded bracket (B) does not have different friction with the new bracket. Differences in design and manufacturing methods of orthodontic bracket affect the friction between orthodontic brackets and archwires even though they use the same material.

An in vitro comparative evaluation of surface roughness characteristics of different orthodontic archwires: An atomic force microscopy study.

Background. The present study evaluated and compared the surface roughness (SR) of five different types of orthodontic archwires made by two different manufacturers. Methods. In this in vitro study, 10 samples of five different archwires comprising of three types of shape memory wires, SmartArch (Ormco), Damon (Ormco), Heat-activated NiTi (HANT) (G&H Orthodontics), Stainless Steel wire (SS) (Ormco), and conventional NiTi (G&H Orthodontics) were examined by atomic force microscopy (AFM). The processing of 3D images was carried out using Gwyddion software, from which the root mean square (rms), the roughness average (Ra), and the maximum height (mh) of the scanned surface profile were documented. The data were analyzed with one-way ANOVA followed by post hoc Tukey tests for intergroup comparisons. Results. The mean SR of SS wires was the least (Ra=8.70±0.17), followed by NiTi wires (10.29±2.00) with a significant difference between them (P<0.05). Among the three shape-memory wires, the HANT wires had the least SR (Ra=22.97±16.56) compared to SmartArch wires (Ra=25.55±3.78) and Damon wires (Ra=25.67±4.54), but the difference was not significant (P>0.05). Conclusion. The SS wires by Ormco had the least SR followed by G&H orthodontics NiTi wires. The three different shape-memory wires tested had no significant difference in SR values.

Evaluation of pain in patients undergoing fixed dental appliance

Introduction: Pain is experienced by patients during various fixed orthodontic procedures such as placement of separators, insertion of arch wire and its activations, orthopedic appliances such as headgear, and debonding of the appliance. This study was formulated with the background that the level of pain sensation differs between conventional metal and ceramic brackets, arch wire being the same pain is an important aspect of oral health-related quality of life (OHRQOL). Understanding how patients' pain experiences during their treatment affect their quality of life (QOL) is important and the absence of pain/discomfort is important for achieving a high QOL. Aim and Objective: The objective of this study was to assess the relationship between pain and OHRQOL among patients wearing fixed orthodontic appliances and to evaluate whether patient motivation and counseling had an effect on the pain and discomfort. Materials and methods: The data collection was done , the obtained data were tabulated and entered in the MS excel sheet. Data collection were imported to SPSS, variable definition process was done using tables and graphical illustration.

Assessment of impact of fluoride on mechanical properties of NiTi and Cu NiTi orthodontic archwires

Background: The current study was carried out to assess the impact on the mechanical properties of orthodontic wires such as the NiTi and CuNiTi wires by fluoride available in various prophylactic products. Materials &amp; methods: 80 wire specimens were selected and were divided into two study groups with 20 specimens in each group as follows”: Group A: 0.019 x 0.025 inch NiTi archwires (NT3, American Orthodontics,USA), Group B: 0.019 x 0.025 inch CuNiTi archwires (Tritanium, American Orthodontics,USA). Following fluoride agent was taken as standard for the present study: Phos-Flur gel (Colgate oral pharmaceuticals, New York, USA). From the straight part of the archwire enrolled in the present study, wire specimens of dimensions 0.40 X 0.60 X 20 mm were cut. Control group: 40 specimens consisting of 20 specimens from each wire type; Solution used was deionized water, and Study group: 40 specimens consisting of 20 specimens from each wire group, placed in the Phos-Flur gel. Random selection of the wires was done followed by testing under universal force testing machine. Results: Among the study groups subjects, mean loading force among group A and group B specimens was 596.1 MPa and 368.4 MPa respectively.

Third-Order Effects and Maxillary Incisor Control in Lingual Orthodontics – A Finite Element Study of a Ribbon Arch and Edgewise Straight Wire System

Introduction: The aim of the present study was to analyze the effects of retraction mechanics on torque control when retraction forces were applied on the maxillary anterior dentition in two distinct lingual appliance systems. Materials and Methods: A three-dimensional bilateral maxillary model was created where the first premolar extraction case was included. 150 g (1.47 N) of retraction force was applied on each side from canine (C) hook to molar for both edgewise straight wire system and ribbonarch appliances. Results: In the edgewise appliance, it was observed in the X-axis that there was less amount of tipping of the six anterior teeth of the canine and central incisor (CI) when compared with the lateral incisor (LI) at occlusal point. In the Y-axis, overall extrusion was observed. In the Z-axis, there was less lingual crown movement. In the ribbonarch appliance, it was observed in the X-axis that there was less tipping, prominently in the canine and CI than in the LI. In the Y-axis, overall extrusion was observed. In the Z-axis, there was less lingual crown movement, whereas the CI and canine showed less movement when compared with the LI. Conclusions: It was observed that there was greater torque loss and extrusion in the edgewise appliance along with greater maximum principal stress in the cervical half of the facial side in the periodontal ligament (PDL) and minimum principal stress on the cervical half of the palatal side in the PDL when compared with the ribbonarch appliance.

Effect of Graphene Sheets Embedded Carbon Films on the Fretting Wear Behaviors of Orthodontic Archwire-Bracket Contacts.

Carbon films were fabricated on the orthodontic stainless steel archwires by using a custom-designed electron cyclotron resonance (ECR) plasma sputtering deposition system under electron irradiation with the variation of substrate bias voltages from +5 V to +50 V. Graphene sheets embedded carbon (GSEC) films were fabricated at a higher substrate bias voltage. The fretting friction and wear behaviors of the carbon film-coated archwires running against stainless steel brackets were evaluated by a home-built reciprocating sliding tribometer in artificial saliva environment. Stable and low friction coefficients of less than 0.10 were obtained with the increase of the GSEC film thickness and the introduction of the parallel micro-groove texture on the bracket slot surfaces. Particularly, the GSEC film did not wear out on the archwire after sliding against three-row micro-groove textured bracket for 10,000 times fretting tests; not only low friction coefficient (0.05) but also low wear rate (0.11 × 10−6 mm3/Nm) of the GSEC film were achieved. The synergistic effects of the GSEC films deposited on the archwires and the micro-groove textures fabricated on the brackets contribute to the exceptional friction and wear behaviors of the archwire-bracket sliding contacts, suggesting great potential for the clinical orthodontic treatment applications.

Surgical Orthodontic Treatment of Class II Malocclusion with Facial Asymmetry

This case report describes a successful surgical orthodontic treatment of a Class II malocclusion with facial asymmetry. An 18-year-old female visited our dental clinic due to proclined anterior teeth and facial asymmetry. Straight facial profile and skeletal Class II was observed. The frontal cephalometric analysis showed that the left ramus length was longer and the left ramal angle was greater than the right. After extraction of the maxillary and mandibular second premolars, dental arch was decompensated. After presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy (BSSRO) was performed. Facial asymmetry was improved, but posterior open bite on the right was occurred by insufficient dental decompensation. To prevent recurrence of the mandible, a bite stop was made by bonding resin on the lingual side of the right maxillary canine. This prevented the recurrence of the mandibular rolling and yawing with the use of bilateral intermaxillary elastics. The right mandibular posterior part with open bite was segmented from the main arch wire and was extruded with intermaxillary elastic. Fast occlusal stabilization was achieved by using the rapid tooth movement after surgery. Since intermaxillary elastic was used while applying an intrusion force with a micro-implant to the left posterior region, it was possible to stabilize the mandible while prevent tooth extrusion. After treatment, facial symmetry and good occlusal relationship were achieved.

Orthodontic Treatment for Adult Patients with Scissors Bite Using Tiggle Brackets

Due to the difficulty of correcting scissors bite, so many treatment modalities have been suggested. One of them are crisscross elastics, orthodontic miniscrews, trans-palatal arch with precision lingual arch wire, and so on. Tiggle brackets are one of minitubes which was recently introduced for the treatment of anterior teeth. It is designed to be positioned on the lingual surfaces of the anterior teeth. They exert very light force, so the counteraction is very small with minimum side effect. With their small size, it is good to bond on the teeth with scissors bite, reducing the possibility of falling off during masticatory movement. Tiggle brackets can be a very useful orthodontic treatment modality when correcting scissors bite.

Effect of fine particle shot peening on surface friction of stainless steel and ceramic bracket slots

This study aims to compare the static friction of untreated and fine particle shot peening (FPSP) treated stainless steel and ceramic bracket slots. A total of 60 pieces of stainless steel and 60 pieces of ceramic brackets (Roth prescription, 0.022×0.028 in2) were divided into 3 groups: control (n=20), silica glass bead particle surface treatment (n=20) and stainless steel (SUS316L) particle surface treatment (n=20). Ten brackets of each group were combined with 0.019×0.025 in2 orthodontic stainless steel arch wires and were analyzed for static friction. The remaining 10 brackets of each group were tested for slot surface roughness and hardness. The result shows that stainless steel brackets treated with FPSP exhibited lower static friction, with smoother and harder surfaces than the control group (p<0.05). In contrast, treated ceramic brackets showed no difference from the control group in terms of static friction, roughness, and hardness (p>0.05).

Effect of Fluoride Content of Mouthwashes on Superelastic Properties of NiTi Orthodontic Archwires.

The influence of sodium fluoride (NaF) concentration in mouthwashes on the properties of superelastic NiTi orthodontic wires has been studied. In this work, 55.8%Ni and 44.2%Ti (in weight) wires were introduced in commercial mouthwashes with different NaF contents (0, 130, 200 and 380 ppm). The release of Ni2+ and Ti4+ ions was by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) at 1, 4, 7 and 14 days. Superelastic orthodontic wires present at oral temperature the austenitic phase which is transformed into a plastic phase (martensite) by cooling. The temperatures at which this occurs are influenced by the chemical composition. The release of ions from the wire will produce variations in the temperatures and stresses of the stress-induced martensitic transformation. Ms, Mf, As, Af were determined by Differential Scanning Calorimeter (DSC). The transformation stresses (austenite to stress induce martensite) were determined with a servo-hydraulic testing machine at 37 °C. The surfaces for the different times and mouthwash were observed by Scanning Electron Microscope (SEM). The release of Ni2+ in mouthwashes with 380 ppm NaF concentrations reaches 230,000 ppb in 14 days and for Ti4+ 175,000 ppb. When NaF concentrations are lower than 200 ppm the release of Ni and Ti ions is around 1500 ppb after 14 days. This variation in compositions leads to variations in Ms from 27 °C to 43.5 °C in the case of higher NaF concentration. The increasing immersion time and NaF concentrations produce a decrease of Ni in the wires, increasing Ms which exceed 37 °C with the loss of superelasticity. In the same way, the stresses (tooth position corrective) decrease from 270 MPa to 0 MPa due to the martensitic phase. The degradation can produce the growth of precipitates rich in Ti (Ti2Ni). These results are of great interest in the orthodontic clinic in order to avoid the loss of the therapeutic properties of superelastic NiTi due to long immersion in fluoride mouthwashes.

Establishment, FEM analysis and experimental validation of tooth movement prediction model of orthodontic archwire T-loop

BackgroundThe T-loop has been used clinically to close gap between teeth. And it is a typical orthodontic archwire bending method. However, the design of the T-loop parameters for different patients is based on the clinical experience of the dentists. The variation in dentists' clinical experience is the main reason for inadequate orthodontic treatment, even high incidence of postoperative complications.MethodsFirstly, the tooth movement prediction model is established based on the analysis of the T-loop structure and the waxy model dynamic resistance. As well as the reverse reconstruction of the complete maxillary 3D model based on the patient CBCT images, the oral biomechanical FEM analysis is completed. A maxillary waxy dental model is manufactured to realize the water-bath measurement experiment in vitro mimicking the oral bio-environment. Thus, the calculated, simulation and experimental data are obtained, as well as obtaining a cloud of total deformation from the simulation analysis.ResultsThe growth trend of the 11 sets of simulation data is the same as that of the experimental data. And all of them show that the tooth displacement is positively correlated with the cross-sectional size of the archwire, and the clearance distance. As well as the higher Young's modulus of the archwire material, the greater the tooth displacement. And the effect of archwire parameters on tooth displacement derived from simulation and experimental data is consistent with the prediction model. The experimental and calculated data are also compared and analyzed, and the two kinds of data are basically consistent in terms of growth trends and fluctuations, with deviation rates ranging from 2.17 to 10.00%.ConclusionsThis study shows that the accuracy and reliability of the tooth movement prediction model can be verified through the comparative analysis and deviation calculation of the obtained calculated, simulation and experimental data, which can assist dentists to safely and efficiently perform orthodontic treatment on patients. And the FEM analysis can achieve predictability of orthodontic treatment results.

Clinical contemplation and management of multiple impacted canines

The impaction of the maxillary canines causes relevant a esthetic and functional problems. The multidisciplinary approach to the proper planning and execution of orthodontic traction of the element in question is essential. Many strategies are cited in the literature among the mis the good biomechanical control in order to avoid possible side effects. The aim of this paper is to present a case report in which a superior canines impacted by palatine was pulled out with the aid of direct traction with the help of elastics and arch wires. A 19-year-old male patient reported with a chief complaint of malaligned teeth and missing some teeth. The proposed treatment prioritized the traction of the upper right canine without changing the occlusion and aesthetics. For this, straight wire appliance with .022 slot was inserted in order to minimize unwanted side effects. The use of cantilever to the traction of the upper right canine has enabled an efficient and predictable outcome, because it is of statically determined mechanics. Comprehensive orthodontic therapy along with surgical exposure of 13, 33 and 43 helped in achieving all the treatment objectives to great satisfaction without any adverse effects on the periodontium or the dentition.

A Comparative Study of Intermolar Arch Width before and after Orthodontic Treatment in Alignment Phase among Class II Div-I Patients

For an orthodontist, changes in the width of the arch caused by treatment with fixed appliances are important. Understanding these changes is critical to your physician's planning for treatment. Aim: The purpose of the study was to compare and determine the width of the inter- molar arch in cases of class II, division 1 before and 4 months after fixed orthodontic treatment. Study Design: A cross-sectional intervention study. Place and Duration: In the Orthodontics department of Jam Ghulam Qadir Govt. Hospital, Hub Govt of Balochistan and Bhitai Dental and Medical College Mirpurkhas, for six-months duration from July 2021 to December 2021. Methods: 200 Class II Division 1 malocclusion patients were included by the purposive non- probability technique of sampling. 14 to 28 years was the patients age range. The impressions of the upper arch were measured before and six months after orthodontic treatment, and the maxillary inter-molar width was measured. Standard 0.012 Nitinol to 0.019x0.028 arch wires were used. The width of the inter-molar arch was taken as the transverse distance from the central fossa of the 1st molar on one side of the same arch to the central fossa of the 1st molar on the same arch of other side. Results: 200 Class II Division 1 malocclusion patients were included (120 males and 80 females) with 14-28 years of age range and 18.24 ± 2.8 years of mean age. The mean values of the inter-molar width in the entire sample were 46.01 mm ± 2.58 mm in T1 and 48.201 mm ± 2.70 mm in T2 (Table 2). The mean width of the inter-molar arches in men and women before treatment was 43.7± 2.2 mm and 46.2 ± 2.8 mm. Though, the mean T2 inter-molar arch width after treatment was 47.1 ± 2.3 mm in women and 48.3 ± 2.7 mm in men. Conclusion: There was an average rise in the width of the inter-molar arch by 1.7 mm before and after treatment, therefore the orthodontist should consider the mechanics of expanding the arch, especially when the treatment plan does not include extractions. Keywords: width of the inter-molar arch, shape of the arch, malocclusion class II division 1

Three dimensional modeling and numerical analysis of hydrogen effects on the thermomechanical response of Nickel–Titanium orthodontic applications

This paper deals with effects of the hydrogen presence on the thermo-mechanical behavior of NiTi shape memory alloys (SMAs), widely considered for manufacturing orthodontic archwires. A three dimensional phenomenological model is formulated, based on thermodynamics of irreversible processes. It takes into account the experimentally observed effects on the main physical mechanisms (martensitic transformation and reorientation of martensite). The assumption of an additive decomposition between a reversible lattice and a trapped hydrogen concentrations is adopted. The complete problem including chemical, thermal and mechanical balanced equations and their weak form are solved by the finite element method. A 3D hexahedral continuum finite element with five degrees of freedom per node (displacements, temperature and total hydrogen concentration) is developed. Its implementation is carried out in the Abaqus finite element software. Numerical results are presented and compared to experimental ones which show the significant effects of the hydrogen presence in NiTi SMA.

Multi-Loop Edge Wise Arch Wire Technique (MEAW) – A Review

Anterior open bite treatment is considered to be a complex treatment in the field of orthodontics. Orthognathic surgery is often the treatment of choice for these types of malocclusions and prognosis of the results are still questionable. With the introduction of Multiloop edgewise archwire therapy, treatment of open bite has started showing efficient results. Moreover, MEAW is versatile as it is capable of correcting various malocclusions as well such as Class II, Class III, deep overbite, and malocclusions with marked midline deviations. Since the advent of the MEAW, its treatment modality has been used worldwide and numerous reports of successful results have been published. Some orthodontists have described the MEAW technique as “magical” or “unbelievable,” but it certainly is not. The diagnosis and treatment plan must be correct and construction of the MEAW must be precise to deliver the necessary forces to move the teeth to an optimal, stable relationship.Hence this article aims to review the multiloop edge wise arch wire technique in detail along with its biomechanics.

Effect of Bracket Width on Bending Deformation of NiTi Arch Wire: A Finite Element Study

The force transferred from the NiTi arch wire to the tooth during orthodontic treatment is strongly dependent on the geometry of the wire and brackets used by the orthodontist. This study investigated the effect of orthodontic bracket geometry on the bending behaviour of superelastic NiTi arch wire. A three-dimensional finite element models of wire bending in three-brackets configuration was developed by employing superelastic user material subroutine and contact interaction. The finite element model was used to anticipate the bending forces and stresses of NiTi wires as they were engaged in various slot width dental brackets. Four different bracket widths were considered, ranging from 1.5 mm to 4.5 mm. Throughout the bending course, the superelastic NiTi wire bent in the 4.5 mm width bracket continuously demonstrated the highest bending force in comparison to the other bracket widths. As the bracket width was raised from 1.5 mm to 4.5 mm, the wire unloading force measured at 2.5 mm deflection increased gradually from 0.40 N to 1.7 N. The bending stress of the wire deformed in the 1.5 mm width bracket was 543 MPa, band it increased to 1051 MPa when the 4.5 mm width bracket was used. The proportion of complete martensite structure at the wire curvature gradually increased as the width of the bracket slot was increased.

Efficacy of lower arch leveling, lower incisors’ root resorption, and pain associated with the correction of curve of Spee using different orthodontic archwires: a randomized clinical trial

ObjectivesTo compare between 3 archwires (AWs) for leveling curve of Spee (COS) in terms of efficacy of reduction, external apical root resorption (EARR), pain experienced, and the lower arch dimensional changes during COS leveling.Trial designRandomized clinical trial.SettingJordan University of Science and Technology Postgraduate dental clinics.Material and methodsFifty-three subjects with COS > 5 mm were included in this study. The subjects were randomly divided into three groups based on the AW used: group 1, 0.017 × 0.025-inch stainless-steel (SS) AW; group 2, 0.019 × 0.025-inch SS AW; and group 3, 0.021 × 0.025-inch β-titanium (TMA) AW. The intervention was randomly allocated using the permuted random block size of 3 with a 1:1:1 allocation ratio. In the three groups, a 5-mm depth reverse COS was placed in the AWs. The following time points were defined for COS assessment: T1, before interventional leveling AW placement; and T2–T7, 1–6 months after interventional leveling AW placement. Records consisted of dental study models and periapical (PA) radiographs. Pain scores were recorded using visual analogue scale. Patients were followed up on a monthly basis until COS < 1.5 mm.Main outcome measuresCOS depth reduction, lower incisors’ EARR, pain scores, and arch dimensional changes.ResultsAn overall reduction of 3.82 mm, 4.47 mm, and 3.85 mm of the depth of COS was achieved in groups 1, 2, and 3, respectively. The mean differences of 0.65 mm between groups 1 and 2 and 0.62 mm between groups 2 and 3 were significant at P < 0.05. Lower incisors’ EARR during leveling COS ranged from 0.68 to 0.72 mm, from 0.63 to 0.82 mm, and from 0.53 to 0.88 mm in groups 1, 2, and 3, respectively (P > 0.05). Higher pain scores were reported by group 2 subjects during the first 24 h. Arch length and width increased significantly in groups 2 and 3 (P < 0.05). In all groups, COS leveling was achieved by lower incisor intrusion and proclination and lower molar extrusion.ConclusionsAll investigated AWs were effective in leveling COS with minimal lower incisors’ EARR (< 1 mm). COS was leveled by lower incisors’ intrusion and proclination and lower molar extrusion. Pain scores were the highest in group 2 during the first 24 h.Clinical relevanceThe 3 investigated leveling AWs were effective for the leveling COS and at the same time safe on the roots of the lower anterior teeth.

Friction forces generated by aesthetic Gummetal® (Ti-Nb) orthodontic archwires: A comparative in vitro study

The aim of this in vitro study was to compare friction forces generated by the following archwires: rhodium-plated aesthetic Gummetal® (E-GM), Gummetal® (GM), stainless steel (SS) and titanium-molybdenum alloy (TMA), according to bracket-wire angulation and archwire cleanliness. One hundred and ninety-two samples of four orthodontic alloys (E-GM, GM, SS, and TMA) were prepared. The samples were divided into two groups: uncleaned and cleaned using 99% isopropanol in an ultrasonic bath, then subdivided into three subgroups according to bracket-wire angulation: 0°, 5° and 10°. Using a universal testing machine, the wires were pulled through SS maxillary right canine brackets to test static friction forces according to bracket-wire angulation and wire cleanliness. Representative specimens were evaluated to assess surface morphology and roughness. There were significant differences in static friction forces between archwires when analysed by bracket-wire angulation and cleanliness (P<0.001) except for the 0° uncleaned group. Overall, TMA archwires produced the highest friction while SS wires showed the lowest friction at 0° and 5°. E-GM wires showed comparable friction to SS at 0o (cleaned and uncleaned), but significantly higher friction than SS at 5o (uncleaned) and 10° (cleaned). GM wires had comparable friction to SS at 0° (cleaned and uncleaned), but significantly less friction at the 5° (cleaned) and 10° (cleaned and uncleaned). Compared to GM, E-GM had significantly higher friction at 5o and 10° (cleaned and uncleaned). Cleaning wires reduced surface roughness but increased overall friction. E-GM wires generate higher frictional resistance forces compared to GM and SS, especially at higher bracket-wire angulations and when cleaned. GM friction forces are comparable to SS and thus could be used for space closure with sliding mechanics. However, E-GM wires are not ideal for the same purpose.