Corrosion Resistance in Artificial Saliva and Nutrition Media with Different Acidity of Two Types Ni-based Dental Alloys Obtained by Powder Metallurgical and Conventional Methods

Abstract The presented paper studies the effect of the casting technology on the corrosion resistance of Co-Cr-Mo alloy. The investigations were conducted on a commercial alloy with the brand name ARGELOY N.P SPECIAL (Co-Cr-Mo) produced by Argen as well as the same alloy melted and cast by the lost wax casting method performed by a dental technician. The corrosion behavior of the dental alloys in an artificial saliva was studied with the use of the following electrochemical techniques: open circuit potential and voltammetry. After the electrochemical tests, studies of the surface of the examined alloys were performed by means of a scanning electron microscope with an X-ray microanalyzer. The results of the electrochemical studies show that the dependence of the corrosion resistance on the microstructure associated with the recasting process is marginal. The results of the electrochemical studies of the considered alloy clearly point to their good corrosion resistance in the discussed environment.

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Investigation of the Microstructure, Hardness and Corrosion Resistance of a New 58Ag24Pd11Cu2Au2Zn1.5In1.5Sn Dental Alloy

Materials ◽

10.3390/ma12244199 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4199 ◽

Cited By ~ 1

Author(s):

Dan Gheorghe ◽

Ion Pencea ◽

Iulian Vasile Antoniac ◽

Ramona-Nicoleta Turcu

Keyword(s):

Solid Solution ◽

Corrosion Resistance ◽

Corrosion Behavior ◽

Artificial Saliva ◽

Complex Structure ◽

Electrochemical Corrosion ◽

Dental Alloy ◽

Dental Alloys ◽

Cu Content ◽

Electrochemical Corrosion Behavior

Higher-noble dental alloys (Au, Ag, and Pd) are the most desirable for dentistry applications, but they are expensive. Low-noble (Ag, Pd, Cu) dental alloys are alternatives to higher-noble ones due to their lower price. In this regard, the paper supports the price lowering of dental alloy by increasing the Cu content, i.e., a new 58Ag24Pd11Cu2Au2Zn1.5In1.5Sn dental alloy. The increasing addition of the Cu leads to a complex structure consisting of a solid solution that engulfs compounds of micrometric and nanometric sizes. The 58Ag24Pd11Cu2Au2Zn1.5In1.5Sn has demonstrated a much better electrochemical corrosion behavior in artificial saliva compared to the Paliag and Unique White dental alloys. The improved corrosion behavior of the new alloy is supported by the diminishing of the Cu selective diffusion into the electrolyte due to its retaining into compounds and into Ag-Pd solid solution. Also, the synergic effects of Cu, Zn, In, Sn may improve the corrosion resistance, but they have strengthened the 58Ag24Pd11Cu2Au2Zn1.5In1.5Sn matrix. The main finding addressed in the paper consists in a new 58Ag24Pd11Cu2Au2Zn1.5In1.5Sn dental alloy with improved corrosion resistance in artificial saliva.

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Influence of Khat Extract (Catha edulis) on Corrosion Resistance of Co-Cr Dental Alloys

Brazilian Dental Science ◽

10.14295/bds.2021.v24i2.2248 ◽

2021 ◽

Vol 24 (2) ◽

Author(s):

Rassam Al-Subari ◽

Nadia Merzouk ◽

Nasser Kabak ◽

Abdullah Guenbour ◽

Sadeq Ali Al-Maweri ◽

...

Keyword(s):

Corrosion Resistance ◽

Surface Analysis ◽

Electrochemical Impedance ◽

Negative Impact ◽

Artificial Saliva ◽

In Vivo Studies ◽

Reference Solution ◽

Dental Alloys ◽

Catha Edulis ◽

Removable Denture

Objective: The aim of this experimental study was to assess the effect of khat extract with different concentrations on the corrosion resistance of cobalt-chromium (Co-Cr) dental alloys used for removable denture. Material and Methods: The corrosion resistance of three Co-Cr alloys (Neobond II®, Kera 501® and PD Casta H®) was evaluated in artificial saliva in presence of three different concentrations of khat extracts. Fusayama-Meyer artificial saliva was used as a reference solution. The corrosion properties of the alloys were analyzed using potentiodynamic polarization, electrochemical impedance spectroscopy and surface analysis. The data was presented in means, standard deviations, and related figures. Comparison between the different concentrations was done using 1-way ANOVA test. The surface analysis was performed using scanning electron microscopy (SEM). Results: the results showed that the corrosion resistance of the three alloys tested (Neobond II®, Kera 501® and PD Casta H®) decreased in artificial saliva containing khat extract compared with that of the reference solution. Additionally, the corrosion resistance of the three Co-Cr dental alloys decreased by increasing the concentration of khat extract. Furthermore, the results indicate that Neobond II® alloy showed the least corrosion resistance compared with that of Kera 501® and PD Casta H® alloys. Conclusion: Khat extract with different concentrations had negative impact on the corrosion resistance of Cr-Co alloys. More in-vivo studies are highly recommended to confirm the results of the present study Keywords Khat; Catha edulis; Partial denture; Corrosion resistance.

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Corrosion Behavior of TiSiN Coatings Deposited on Ni-Cr Alloy in Artificial Saliva with and without Fluoride

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.638.47 ◽

2015 ◽

Vol 638 ◽

pp. 47-53 ◽

Cited By ~ 1

Author(s):

Mihaela Dinu ◽

Mariana Braic ◽

M. Tarcolea ◽

Alina Vladescu ◽

Iulian Vasile Antoniac ◽

...

Keyword(s):

Corrosion Resistance ◽

Artificial Saliva ◽

Critical Value ◽

Mineral Dissolution ◽

Substrate Bias ◽

Dental Alloys ◽

Dental Tissue ◽

Testing Environment ◽

Corrosion Evaluation ◽

Cathodic Arc

TiSiN thin films were deposited on NiCr dental alloy in order to enhance the corrosion resistance in artificial saliva with and without fluoride content. The TiSiN films were prepared using reactive cathodic arc method at two different substrate bias voltages (-50 V and-200 V). For the corrosion evaluation, artificial saliva with pH=5.2 was chosen, because this is a critical value for mineral dissolution of dental tissue which can affect the dental alloys. A content of 0.1 % NaF was added to the artificial saliva to simulate the effect of fluoride based hygiene products. The TiSiN coated NiCr alloys exhibited a higher corrosion resistance than the NiCr substrate, irrespective of the testing environment. The best corrosion resistance was found for the TiSiN deposited at-200 V.

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Experimental Study Regarding the Behavior at Different pH of Two Types of Co-Cr Alloys Used for Prosthetic Restorations

Materials ◽

10.3390/ma14164635 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4635

Author(s):

Farah Bechir ◽

Simona Maria Bataga ◽

Elena Ungureanu ◽

Diana Maria Vranceanu ◽

Mariana Pacurar ◽

...

Keyword(s):

Corrosion Resistance ◽

Corrosion Behavior ◽

Polarization Resistance ◽

Ph Value ◽

Artificial Saliva ◽

Corrosion Current ◽

Open Circuit ◽

Dental Alloys ◽

Cobalt Chromium ◽

Electrochemical Parameters

Cobalt-chromium (Co-Cr) alloys are widely utilized in dentistry. The salivary pH is a significant factor, which affects the characteristics and the behavior of dental alloys through corrosion. This study aimed to evaluate the corrosion behavior in artificial saliva with different pH values (3, 5.7, and 7.6) of two commercial Co-Cr dental alloys manufactured by casting and by milling. Corrosion resistance was determined by the polarization resistance technique, and the tests were carried out at 37 ± 1 °C, in Carter Brugirard artificial saliva. After the electrochemical parameters, it can be stated that the cast Co-Cr alloy has the lowest corrosion current density, the highest polarization resistance, and the lowest speed of corrosion in artificial saliva with pH = 7.6. In the case of milled Co-Cr alloy, the same behavior was observed, but in artificial saliva with pH = 5.7, it recorded the most electropositive values of open circuit potential and corrosion potential. Although both cast and milled Co-Cr alloys presented a poorer corrosion resistance in artificial saliva with a more acidic pH value, the milled Co-Cr alloy had better corrosion behavior, making this alloy a better option for the prosthetic treatment of patients suffering from GERD.

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Orthodontic wires of Ni-Cr and Ni-Ti alloys and its corrosion resistance in the absence and presence of Erythromycin tablets 500mg in artificial saliva

Asian journal of biochemical and pharmaceutical research ◽

10.24214/ajbpr/8/4/120127 ◽

2018 ◽

Vol 8 (4) ◽

Keyword(s):

Corrosion Resistance ◽

Artificial Saliva ◽

Orthodontic Wires ◽

Ti Alloys

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Study of Electrochemical Behavior of Some Dental Alloys

Revista de Chimie ◽

10.37358/rc.18.6.6377 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1598-1602

Author(s):

Alice Arina Ciocan Pendefunda ◽

Constanta Mocanu ◽

Doriana Agop Forna ◽

Cristina Iordache ◽

Elena Luca ◽

...

Keyword(s):

Oral Cavity ◽

Electrochemical Behavior ◽

Base Alloy ◽

Artificial Saliva ◽

Surface Condition ◽

Continuous Process ◽

Metal Alloys ◽

Alloy Surface ◽

Dental Alloys ◽

Dental Restorations

The purpose of the study is to investigate the electrochemical behavior of two dental alloys: palladium alloy (Palidor) and Ni-Cr alloy (Verasoft) in three types of artificial saliva. Determination of corrosion potential and recording of linear and cyclic polarization curves were performed with PGP201 potentiostat (VoltaLab 21- Radelkis Copenhagen. In order to study the modifications produced on the surface of the electrodes, a complex optical microscope MC 1 research type (IOR, Romania) was used, adapted to a digital camera, which was connected to a computer for the digital acquisition of images . Two metal alloys based on Ag-Pd and Ni-Cr were used for the experiments. The materials used came from different types of dental restorations removed from the oral cavity of the patients after a 5-15 years period. As corrosion environments, three artificial saliva were used: Fusayama, Afnor and Rondelli. The Pd-Ag dental alloy exhibits a very good corrosion resistance and the treatment in the Afnor saliva does not affect the surface of the alloy. Electrochemical behavior in Fusayama-Meyer�s saliva of the alloy surface results in a series of spots representing deposits of insoluble salts resulting from the oxidation process, while in the Rondelli saliva there is a series of small corrosion points on the alloy surface. The behavior of the Verasoft alloy in the Afnor and Rondelli saliva is similar; In both solutions, the potential breakthroughs are very close, but in Fusayama-Meyer�s saliva, the potential for initiation of corrosion points is very low (206 mV), a potential that can be encountered in the oral cavity. All metals and metal alloys, even the noble and semi-precious ones, are susceptible to corrosion, forming compounds with properties different from those of the metal or base alloy, which change their surface condition. Metallic dental restorations are permanently affected by the factors of the oral environment (physical-mechanical, chemical and biological), being subjected to a continuous process of degradation.

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A Comparative Electrochemical and Morphological Investigation on the Behavior of NiCr and CoCr Dental Alloys at Various Temperatures

Metals ◽

10.3390/met11020256 ◽

2021 ◽

Vol 11 (2) ◽

pp. 256

Author(s):

Florentina Golgovici ◽

Mariana Prodana ◽

Florentina Gina Ionascu ◽

Ioana Demetrescu

Keyword(s):

Low Temperatures ◽

Artificial Saliva ◽

Electrochemical Stability ◽

Morphological Investigation ◽

Dental Alloys ◽

Ion Release ◽

Icp Ms ◽

Different Temperatures ◽

Good Concordance ◽

Increasing Temperature

The purpose of our study is to compare the behavior of two reprocessed dental alloys (NiCr and CoCr) at different temperatures considering the idea that food and drinks in the oral cavity create various compositions at different pH levels; the novelty is the investigation of temperature effect on corrosion parameters and ion release of dental alloys. Electrochemical stability was studied together with morphology, elemental composition and ions release determination. The results obtained are in good concordance: electrochemistry studies reveal that the corrosion rate is increasing by increasing the temperature. From SEM coupled with EDS, the oxide film formed on the surface of the alloys is stable at low temperatures and a trend to break after 310K. ICP-MS results evidence that in accordance with increasing temperature, the quantities of ions released from the alloys immersed in artificial saliva also increase, though they still remain small, less than 20 ppm.

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Influence of HAP on the Morpho-Structural Properties and Corrosion Resistance of ZrO2-Based Composites for Biomedical Applications

Crystals ◽

10.3390/cryst11020202 ◽

2021 ◽

Vol 11 (2) ◽

pp. 202

Author(s):

Réka Barabás ◽

Carmen Ioana Fort ◽

Graziella Liana Turdean ◽

Liliana Bizo

Keyword(s):

Electrochemical Impedance ◽

Artificial Saliva ◽

Synergetic Effect ◽

Composite Layer ◽

Charge Transfer Resistance ◽

Processing Route ◽

Dental Alloys ◽

Metallic Electrode ◽

Transfer Resistance ◽

X Ray

In the present work, ZrO2-based composites were prepared by adding different amounts of antibacterial magnesium oxide and bioactive and biocompatible hydroxyapatite (HAP) to the inert zirconia. The composites were synthesized by the conventional ceramic processing route and morpho-structurally analyzed by X-ray powder diffraction (XRPD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Two metallic dental alloys (i.e., Ni–Cr and Co–Cr) coated with a chitosan (Chit) membrane containing the prepared composites were exposed to aerated artificial saliva solutions of different pHs (i.e., 4.3, 5, 6) and the corrosion resistances were investigated by electrochemical impedance spectroscopy technique. The obtained results using the two investigated metallic dental alloys shown quasi-similar anticorrosive properties, having quasi-similar charge transfer resistance, when coated with different ZrO2-based composites. This behavior could be explained by the synergetic effect between the diffusion process through the Chit-composite layer and the roughness of the metallic electrode surface.

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Susceptibility to Stress Corrosion of Laser-Welded Composite Arch Wire in Acid Artificial Saliva

Advances in Materials Science and Engineering ◽

10.1155/2013/738954 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8

Author(s):

Chao Zhang ◽

Xinhua Sun

Keyword(s):

Weight Loss ◽

Stainless Steel ◽

Corrosion Resistance ◽

Shape Memory Alloy ◽

Artificial Saliva ◽

Steel Wire ◽

Niti Shape Memory Alloy ◽

Solution Ph ◽

Corrosion Behaviors ◽

Cu Interlayer

The corrosion resistance of laser-welded composite arch wire (CoAW) with Cu interlayer between NiTi shape memory alloy and stainless steel wire in artificial saliva with different acidities and loads was studied. It was found that both the solution pH and the stress had a significant influence on the corrosion behaviors of the CoAW samples. Decreasing the solution pH or increasing the loading stress caused the increase of Cu release and weight loss. The corroded morphology formed on the surfaces of the CoAW was the consequence under the combined effect of corrosion and stress.

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