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Progress in Orthodontics Feb 2018Corrosion resistance is an important requirement for orthodontic appliances. Nickel and chromium may be released from orthodontic wires and can cause allergic reactions...
BACKGROUND
Corrosion resistance is an important requirement for orthodontic appliances. Nickel and chromium may be released from orthodontic wires and can cause allergic reactions and cytotoxicity when patients use various mouthwashes to whiten their teeth. Our study aimed to assess the release of nickel and chromium ions from nickel titanium (NiTi) and stainless steel (SS) orthodontic wires following the use of four common mouthwashes available on the market.
METHODS
This in vitro, experimental study was conducted on 120 orthodontic appliances for one maxillary quadrant including five brackets, one band and half of the required length of SS, and NiTi wires. The samples were immersed in Oral B, Oral B 3D White Luxe, Listerine, and Listerine Advance White for 1, 6, 24, and 168 h. The samples immersed in distilled water served as the control group. Atomic absorption spectroscopy served to quantify the amount of released ions.
RESULTS
Nickel ions were released from both wires at all time-points; the highest amount was in Listerine and the lowest in Oral B mouthwashes. The remaining two solutions were in-between this range. The process of release of chromium from the SS wire was the same as that of nickel. However, the release trend in NiTi wires was not uniform.
CONCLUSIONS
Listerine caused the highest release of ions. Listerine Advance White, Oral B 3D White Luxe, and distilled water were the same in terms of ion release. Oral B showed the lowest amount of ion release.
Topics: Chromium; In Vitro Techniques; Ions; Mouthwashes; Nickel; Orthodontic Wires; Spectrophotometry, Atomic; Stainless Steel; Surface Properties; Titanium; Tooth Bleaching Agents
PubMed: 29399703
DOI: 10.1186/s40510-018-0203-7 -
The Angle Orthodontist Jul 2018The aim of this research was to assess galvanic behavior of lingual orthodontic brackets coupled with representative types of orthodontic wires.
OBJECTIVES
The aim of this research was to assess galvanic behavior of lingual orthodontic brackets coupled with representative types of orthodontic wires.
MATERIALS AND METHODS
Three types of lingual brackets: Incognito (INC), In-Ovation L (IOV), and STb (STB) were combined with a stainless steel (SS) and a nickel-titanium (NiTi) orthodontic archwire. All materials were initially investigated by scanning electron microscopy / x-ray energy dispersive spectroscopy (SEM/EDX) while wires were also tested by x-ray diffraction spectroscopy (XRD). All bracket-wire combinations were immersed in acidic 0.1M NaCl 0.1M lactic acid and neutral NaF 0.3% (wt) electrolyte, and the potential differences were continuously recorded for 48 hours.
RESULTS
The SEM/EDX analysis revealed that INC is a single-unit bracket made of a high gold (Au) alloy while IOV and STB are two-piece appliances in which the base and wing are made of SS alloys. The SS wire demonstrated austenite and martensite iron phase, while NiTi wire illustrated an intense austenite crystallographic structure with limited martensite. All bracket wire combinations showed potential differences below the threshold of galvanic corrosion (200 mV) except for INC and STB coupled with NiTi wire in NaF media.
CONCLUSIONS
The electrochemical results indicate that all brackets tested demonstrated galvanic compatibility with SS wire, but fluoride treatment should be used cautiously with NiTi wires coupled with Au and SS brackets.
Topics: Alloys; Corrosion; Electrogalvanism, Intraoral; Gold Alloys; Microscopy, Electron, Scanning; Orthodontic Brackets; Orthodontic Wires; Spectrometry, X-Ray Emission; Stainless Steel; X-Ray Diffraction
PubMed: 29509025
DOI: 10.2319/092917-655.1 -
The Angle Orthodontist Nov 2014To analyze the effect of various coating formulations on the mechanical and corrosion properties of nickel-titanium (NiTi) orthodontic wires.
OBJECTIVE
To analyze the effect of various coating formulations on the mechanical and corrosion properties of nickel-titanium (NiTi) orthodontic wires.
MATERIALS AND METHODS
Uncoated, rhodium-coated, and nitrified NiTi wires were observed with a three-point-bend test, surface roughness (Ra) measurement, scanning electron microscopy, energy dispersive spectroscopy, and electrochemical testing (open circuit potential, electrochemical impedance spectroscopy, and cyclic polarization scan). Differences in the properties of tested wire types were analyzed with analysis of variance and Tukey post hoc test.
RESULTS
Uncoated and nitrified NiTi wires showed similar mechanical and anticorrosive properties, while rhodium-coated NiTi wires showed the highest Ra and significantly higher modulus of elasticity, yield strength, and delivery of forces during loading but not in unloading. Rhodium-coated NiTi wires also had the highest corrosion current density and corrosion potential, lowest impedance modulus, and two time constants on Bode plot, one related to the Rh/Au coating and the other to underlying NiTi.
CONCLUSION
Working properties of NiTi wires were unaffected by various coatings in unloading. Nitrification improved corrosion resistance. Rhodium coating reduced corrosion resistance and pronounced susceptibility to pitting corrosion in artificial saliva because of galvanic coupling between the noble coating and the base alloy.
Topics: Coated Materials, Biocompatible; Corrosion; Dental Alloys; Dielectric Spectroscopy; Elastic Modulus; Electrolysis; Gold; Humans; Materials Testing; Microscopy, Electron, Scanning; Nickel; Orthodontic Wires; Pliability; Polarography; Rhodium; Saliva, Artificial; Spectrometry, X-Ray Emission; Stress, Mechanical; Surface Properties; Titanium
PubMed: 24654939
DOI: 10.2319/090413-651.1 -
Dental Press Journal of Orthodontics 2016The aim of the study was to evaluate deflection forces of rectangular orthodontic wires in conventional (MorelliTM), active (In-Ovation RTM) and passive (Damon 3MXTM)...
INTRODUCTION:
The aim of the study was to evaluate deflection forces of rectangular orthodontic wires in conventional (MorelliTM), active (In-Ovation RTM) and passive (Damon 3MXTM) self-ligating brackets.
MATERIAL AND METHODS:
Two brands of stainless steel and nickel-titanium (NiTi) wires (MorelliTM and GACTM), in addition to OrmcoTM copper-nickel-titanium wires were used. Specimens were assembled in a clinical simulation device especially designed for this study and tested in an Instron universal testing machine. For the testing procedures, an acrylic structure representative of the maxillary right central incisor was lingually moved in activations of 0 to 1 mm, with readings of the force released by deflection in unloading of 0.5, 0.8 and 1 mm at a constant speed of 2 mm/min. Inter-bracket forces with stainless steel, NiTi and CuNiTi were individually compared by two-way ANOVA, followed by Tukey's tests.
RESULTS:
Results showed that there were lower forces in conventional brackets, followed by active and passive self-ligating brackets. Within the brands, only for NiTi wires, the MorelliTM brand presented higher forces than GACTM wires.
CONCLUSIONS:
Bracket systems provide different degrees of deflection force, with self-ligating brackets showing the highest forces.
Topics: Alloys; Dental Stress Analysis; Humans; Mechanical Phenomena; Orthodontic Brackets; Orthodontic Wires; Stainless Steel
PubMed: 28125144
DOI: 10.1590/2177-6709.21.6.091-097.oar -
Progress in Orthodontics 2015The purpose of the study is to assess the antiadherent and antibacterial properties of surface-modified stainless steel and NiTi orthodontic wires with silver against... (Comparative Study)
Comparative Study
BACKGROUND
The purpose of the study is to assess the antiadherent and antibacterial properties of surface-modified stainless steel and NiTi orthodontic wires with silver against Lactobacillus acidophilus.
METHODS
This study was done on 80 specimens of stainless steel and NiTi orthodontic wires. The specimens were divided into eight test groups. Each group consisted of 10 specimens. Groups containing uncoated wires acted as a control group for their respective experimental group containing coated wires. Surface modification of wires was carried out by the thermal vacuum evaporation method with silver. Wires were then subjected to microbiological tests for assessment of the antiadherent and antibacterial properties of silver coating against L. acidophilus. Mann-Whitney U test was used to analyze the colony-forming units (CFUs) in control and test groups; and Student's t test (two-tailed, dependent) was used to find the significance of study parameters on a continuous scale within each group.
RESULTS
Orthodontic wires coated with silver showed an antiadherent effect against L. acidophilus compared with uncoated wires. Uncoated stainless steel and NiTi wires respectively showed 35.4 and 20.5 % increase in weight which was statistically significant (P < 0.001), whereas surface-modified wires showed only 4.08 and 4.4 % increase in weight (statistically insignificant P > 0.001). The groups containing surface-modified wires showed statistically significant decrease in the survival rate of L. acidophilus expressed as CFU and as log of colony count when compared to groups containing uncoated wires. It was 836.60 ± 48.97 CFU in the case of uncoated stainless steel whereas it was 220.90 ± 30.73 CFU for silver-modified stainless steel, 748.90 ± 35.64 CFU for uncoated NiTi, and 203.20 ± 41.94 CFU for surface-modified NiTi.
CONCLUSIONS
Surface modification of orthodontic wires with silver can be used to prevent the accumulation of dental plaque and the development of dental caries during orthodontic treatment.
Topics: Anti-Bacterial Agents; Bacterial Adhesion; Bacterial Load; Coated Materials, Biocompatible; Dental Alloys; Desiccation; Humans; Lactobacillus acidophilus; Materials Testing; Metal Nanoparticles; Nickel; Orthodontic Wires; Silver; Stainless Steel; Surface Properties; Titanium; Volatilization
PubMed: 26576557
DOI: 10.1186/s40510-015-0110-0 -
The Angle Orthodontist May 2007To test the antiadherent and antibacterial properties of surface modification of orthodontic wires with photocatalytic titanium oxide (TiO(2)).
OBJECTIVE
To test the antiadherent and antibacterial properties of surface modification of orthodontic wires with photocatalytic titanium oxide (TiO(2)).
MATERIALS AND METHODS
TiO(2) was coated on the surface of the orthodontic wires by a sol-gel thin film dip-coating method. Bacterial adhesion to the wires was evaluated by the weight change of the wires. The antibacterial activity of the surface-modified orthodontic wires was demonstrated by the dilution agar plate method for Streptococcus mutans and spectrophotometry for Porphyromonas gingivalis.
RESULTS
The orthodontic wires coated with the photocatalytic TiO(2) showed an antiadherent effect against S. mutans compared with the uncoated wires. The bacterial mass that bound to the TiO(2)-coated orthodontic wires remained unchanged, whereas that of the uncoated wires increased by 4.97%. Furthermore, the TiO(2)-coated orthodontic wires had a bactericidal effect on S. mutans and P. gingivalis, which cause dental caries and periodontitis, respectively. The antiadherent and antibacterial mechanisms of TiO(2) to break down the cell wall of those bacteria were revealed by scanning electron microscopy.
CONCLUSION
The surface modification of orthodontic wires with photocatalytic TiO(2) can be used to prevent the development of dental plaque during orthodontic treatment.
Topics: Anti-Bacterial Agents; Bacterial Adhesion; Coated Materials, Biocompatible; Orthodontic Wires; Porphyromonas gingivalis; Streptococcus mutans; Surface Properties; Titanium
PubMed: 17465657
DOI: 10.2319/0003-3219(2007)077[0483:SMOOWW]2.0.CO;2 -
Journal of Orthodontics Mar 2024The primary aim of this study was to provide a review of the types and frequency of orthodontic brackets, molar bands and orthodontic auxiliaries used for patients... (Review)
Review
OBJECTIVE
The primary aim of this study was to provide a review of the types and frequency of orthodontic brackets, molar bands and orthodontic auxiliaries used for patients undergoing orthognathic surgery. The secondary aim was to evaluate the risk of failure of these items during orthognathic surgery.
METHODS
From three Dutch hospitals, 124 adult patients were included in this prospective cohort study. Five independent researchers collected the data during surgery using a specifically created data extraction form. The type of surgery, surgeon, orthodontist and type of orthodontic bracket, molar band or auxiliary were noted for each tooth. To evaluate their failure risk, the following variables were noted: failure and site; and type and cause of failure.
RESULTS
Stainless-steel brackets were the most frequently (75.8%) used bracket type seen in patients undergoing orthognathic surgery. Ceramic brackets were seen in 24.2% of the cases and were only applied in the anterior region. Molar bands were present in 58.9% of the patients and mostly with bands on the first molars in combination with bonded tubes on the second molars. In 32.2% of all cases, one or more failures were noted. One-third of all failures were described as detachment of the molar tube on the most posterior molar. Kobayashi ligatures and powerpins showed the highest risk of failure (odds ratio [OR] 3.70, 95% confidence interval [CI] = 1.91-7.15). No significant difference in failure rate was found between stainless-steel brackets, molar bands (OR 0.34, 95% CI = 0.08-1.43) and ceramic brackets (OR 0.44, 95% CI = 0.14-1.45).
CONCLUSION
Stainless-steel brackets, ceramic brackets, molar bands and surgical hooks are suitable for orthognathic cases. Kobayashi ligatures and powerpins had a significantly higher risk of failure so are not recommended for temporary intraoperative maxillomandibular fixation (TIO-MMF).
Topics: Adult; Humans; Orthognathic Surgery; Orthodontic Brackets; Prospective Studies; Molar; Steel; Orthodontic Wires; Stainless Steel; Orthodontic Appliance Design
PubMed: 37462079
DOI: 10.1177/14653125231186825 -
International Journal of Molecular... Apr 2023Surface coating technology is an important way to improve the properties of orthodontic appliances, allowing for reduced friction, antibacterial properties, and enhanced... (Review)
Review
Surface coating technology is an important way to improve the properties of orthodontic appliances, allowing for reduced friction, antibacterial properties, and enhanced corrosion resistance. It improves treatment efficiency, reduces side effects, and increases the safety and durability of orthodontic appliances. Existing functional coatings are prepared with suitable additional layers on the surface of the substrate to achieve the abovementioned modifications, and commonly used materials mainly include metal and metallic compound materials, carbon-based materials, polymers, and bioactive materials. In addition to single-use materials, metal-metal or metal-nonmetal materials can be combined. Methods of coating preparation include, but are not limited to, physical vapor deposition (PVD), chemical deposition, sol-gel dip coating, etc., with a variety of different conditions for preparing the coatings. In the reviewed studies, a wide variety of surface coatings were found to be effective. However, the present coating materials have not yet achieved a perfect combination of these three functions, and their safety and durability need further verification. This paper reviews and summarizes the effectiveness, advantages and disadvantages, and clinical perspectives of different coating materials for orthodontic appliances in terms of friction reduction, antibacterial properties, and enhanced corrosion resistance, and discusses more possibilities for follow-up studies as well as for clinical applications in detail.
Topics: Orthodontic Wires; Friction; Corrosion; Titanium; Materials Testing; Surface Properties; Coated Materials, Biocompatible; Orthodontic Appliances; Anti-Bacterial Agents
PubMed: 37108082
DOI: 10.3390/ijms24086919 -
The Angle Orthodontist May 2022To test a new concept in bracket design-the tip and torque adjustable bracket (TTAB)-to identify its integral ability to change both tip and torque.
OBJECTIVES
To test a new concept in bracket design-the tip and torque adjustable bracket (TTAB)-to identify its integral ability to change both tip and torque.
MATERIALS AND METHODS
The newly designed TTAB underwent independent testing using the orthodontic measurement and simulation system. The TTAB incorporated Roth tip and torque prescription values, with the unique quality of the bracket to enhance or reduce the innate prescribed values of tip (by either +10° or -10°) and torque (by either +7.5° or -7.5°). The TTAB was tested using both the incorporated standard Roth prescription on the rate of canine retraction (sliding mechanics), using 0.018-inch stainless-steel (SS) arch wire, and with alteration of tip values (-10° and +10°). Similarly, frictional measurements and torque evaluations using 0.019 × 0.025-inch SS arch wire were undertaken with the standard prescription and altered torque (+7.5° and -7.5°). In addition, a number of control investigations were performed. Differences were analyzed using analysis of variance.
RESULTS
The rate of observed tooth movement for the TTAB with its prescribed baseline values was comparable to that of the control brackets. Importantly, the alteration of TTAB tip to -10° and +10° significantly (P < .001) increased and reduced, respectively, the rates of canine retraction. In the alteration of torque, at +7.5° and -7.5°, the bracket delivered a moment of +9.3 (2.8) Nmm and -11.9 (3.8) Nmm, respectively, to the lateral incisor (P < .001).
CONCLUSIONS
This in vitro study demonstrates a new concept in preadjusted edgewise bracket design, offering adjustable tip and torque, with the potential for expanded clinical scope.
Topics: Dental Stress Analysis; Materials Testing; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Stainless Steel; Torque
PubMed: 35061018
DOI: 10.2319/061421-474.1 -
Dental Press Journal of Orthodontics 2020This study proposed to investigate the influence of catastrophizing and others factors related to pain during orthodontic treatment.
OBJECTIVE
This study proposed to investigate the influence of catastrophizing and others factors related to pain during orthodontic treatment.
METHODS
27 patients with 0.022 x 0.028-in Straight-wire brackets were evaluated during alignment and leveling phase with nickel-titanium wires. Visual Analog Scales measured the intensity of orthodontic pain at six moments after a clinical appointment: 6 first hours; 1, 2, 3, 5, and 7 days. Multiple linear regression and stepwise approach assessed the influence of the following variables on pain: catastrophizing, sex, age, duration of treatment, clinical appointment time (morning or afternoon), and wire diameter.
RESULTS
The highest pain intensity was reported 24 hours after activation. These data were used to analyze factors associated with pain level. Age (r = 0.062, p= 0.7586), sex (p= 0.28), catastrophizing (r = -0.268, p= 0.1765), and orthodontic wire diameter (r = 0.0245, p= 0.2181) were not correlated with orthodontic pain in the univariate statistics. Catastrophizing was included in the multiple regression model because it was of great interest. Duration of orthodontic treatment (r = 0.6045, p= 0.0008) and the time when orthodontic appliance was activated (p= 0.0106) showed statistical significant associations with pain, and were also included in the multivariate regression, which showed that about 32% of orthodontic pain could be explained by the duration of treatment (R2= 0.32, p= 0.0475). Catastrophizing (R2= 0.0006, p= 0.8881) and clinical appointment time were not significantly associated with pain (R2= 0.037, p= 0.2710).
CONCLUSIONS
Pain after activation of fixed orthodontic appliance is not associated with catastrophizing as well as age, sex, orthodontic wire diameter, and period of activation.
Topics: Catastrophization; Dental Alloys; Humans; Orthodontic Appliance Design; Orthodontic Brackets; Orthodontic Wires; Pain; Titanium
PubMed: 32215479
DOI: 10.1590/2177-6709.25.1.064-069.oar