Surface Micromorphology, Ion Release and Resistance to Corrosion of Orthodontic Wires Aesthetic Coating Subject to Degradation

In the past two decades the utilization of dental and orthopaedic implants in reconstructive surgery has been spread widely. Most of these implants are inserted in the corrosive environment of the human body for long periods of time. The level of dissolution, release, and transport of metal ions as a result of corrosion of these materials are not fully known at present. We report the results of application of micro ion beam PIXE spectroscopy to detect release of titanium from titanium and titanium alloy implants inserted in the tibiae of rabbits for three months. It was found that titanium ions could be detected in the surrounding tissues, with high precision, as a gradient from the implant surface and in higher amounts in the bone tissue as compared with the soft tissues. It is concluded that application of micro ion beam PIXE spectroscopy for detection of metal ion release, and distribution of the released material around the implants with high special resolution and accuracy may be used to further investigate the mechanism of metal release, and the relation between surface micromorphology and corrosion resistance of the implant materials.

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Comparison of Cell Viability and Chemical Composition of Six Latest Generation Orthodontic Wires

International Journal of Biomaterials ◽

10.1155/2021/8885290 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Lina M. Escobar ◽

Jaime Rodrigo Rivera ◽

Eliana Arbelaez ◽

Luisa F. Torres ◽

Andrea Villafañe ◽

...

Keyword(s):

Chemical Composition ◽

In Vitro Study ◽

Polymer Structure ◽

Gingival Fibroblasts ◽

Ion Release ◽

Orthodontic Wires ◽

Surface Characterisation ◽

Coated Wires

Orthodontic wires are made of alloys containing different metals, including nickel. It is important to evaluate their biocompatibility prior to use, owing to their long-term use in patients. This in vitro study compared the cytotoxicity and chemical composition of six latest orthodontic wires: Fantasia®, Tanzo®, FLI®, NT3®, DuoForce®, and Gummetal®. The before-use group consisted of wires that were not used in the mouth, and the after-use group consisted of wires that were used in the mouth for two months. The wires were placed in contact with human gingival fibroblasts (HGF) for 72 h, and cytotoxicity was determined using the resazurin test. The chemical composition and surface characterisation were evaluated by spectrometry and scanning electron microscopy. The groups were compared using ANOVA and Kruskal–Wallis test. Only the FLI® wires produced a 36% reduction in HGF viability ( p < 0.05 ) and presented greater irregularities and loss of polymer structure. After-use wires showed a significant reduction in the percentage of nickel and the appearance of new elements (oxygen and carbon). Therefore, it can be concluded that no toxic ion release was noticed in this study. Rhodium-coated wires were more stable than PTFE-coated wires, and only the FLI® wires showed a slight cytotoxic effect.

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In Vitro Assessment of Nickel Ion Release from Orthodontic Wires

ARC Journal of Dental Science ◽

10.20431/2456-0030.0404001 ◽

2019 ◽

Vol 4 (4) ◽

Keyword(s):

Ion Release ◽

Orthodontic Wires ◽

Nickel Ion ◽

In Vitro Assessment

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Titanium Nitride Plating Reduces Nickel Ion Release from Orthodontic Wire

Applied Sciences ◽

10.3390/app11209745 ◽

2021 ◽

Vol 11 (20) ◽

pp. 9745

Author(s):

Arata Ito ◽

Hideki Kitaura ◽

Haruki Sugisawa ◽

Takahiro Noguchi ◽

Fumitoshi Ohori ◽

...

Keyword(s):

Surface Roughness ◽

Titanium Nitride ◽

Metal Ions ◽

Acid Corrosion ◽

Orthodontic Appliances ◽

Ion Release ◽

Orthodontic Wires ◽

Nickel Ion ◽

Orthodontic Wire ◽

The Wire

The leaching of metal ions from orthodontic appliances is a problem for their use in patients with metal allergies. Despite the development of a number of non-metal orthodontic appliances, including brackets, non-metal wires are not yet available. Therefore, it is necessary to modify the surfaces of orthodontic wires to prevent the leaching of metal ions into the oral environment for use in such patients. This study was performed to examine whether plating of orthodontic wire with titanium nitride (TiN), which does not impair its mechanical properties, could prevent the leaching of metal ions from the wire on immersion in acid. To investigate the acid corrosion resistance of the wire, the amount of metal ions eluted from the wire immersed in acid was measured by using inductively coupled plasma mass spectrometry (ICP-MS) and the dimethylglyoxime (DMG) test, the properties of the wire surface were examined by stereomicroscopy and scanning electron microscopy, and the surface roughness was measured using a surface roughness tester. The results indicated that TiN plating of orthodontic wire significantly suppressed the elution of metal ions on immersion in acid.

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A New Setup for Simulating the Corrosion Behavior of Orthodontic Wires

Materials ◽

10.3390/ma14133758 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3758

Author(s):

Polydefkis Papaioannou ◽

Mona Sütel ◽

Katrin Hüsker ◽

Wolf-Dieter Müller ◽

Theodosia Bartzela

Keyword(s):

Corrosion Behavior ◽

Inductively Coupled Plasma ◽

Material Selection ◽

Dental Materials ◽

Metal Alloy ◽

Ion Release ◽

Orthodontic Wires ◽

Inductively Coupled ◽

Testing Metal ◽

Plasma Mass Spectrometry

The aim of this study was to create a new reliable setup to evaluate commercially available orthodontic wires used during orthodontic treatment. The setup includes various techniques applied for testing metal alloy materials. The materials were tested under extreme conditions to simulate their behavior in the mouth. The alloy composition of each wire was tested. The electrochemical (EC) testing and characterization of the corrosion performance of the wires was calculated by the electrochemical curves at pH = 1 in two different applied potentials to test the reaction of the material. The liquid collected after the EC measurements was analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) to verify the reliability of the EC curves and for a more accurate evaluation of the corrosion behavior of the wires. Therefore, the EC measurements were compared to the actual values obtained from the released ions found in the solution. At the end, a surface analysis was performed to detect corrosion on the wires. In conclusion, this study developed a setup to test and better understand the corrosion behavior and ion release of the orthodontic wires, metal alloy dental materials, and other metals used in the oral cavity. This method can contribute to dental material selection in patients with underlying health conditions.

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