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Galvanic corrosion behavior of implant suprastructure dental alloys
Abstract
The purpose of this study was to evaluate and compare in vitro, the galvanic corrosion behavior of Co-Cr alloys (R2000, R800), Ni-Cr (RCS), silver-palladium (Jelstar), Gold (Pontallor-4) and Ternary Ti (experimental Ter Ti) when coupled with endosseous Ti implant abutment material. Amalgam alloy and commercially pure Ti cylinders (SSTi) were coupled with endosseous Ti implants as negative and positive controls, respectively.
An EG&G Model 263 Scanning Potentiostat was used for this purpose. Specimens were prepared and fresh artificial saliva was used as an electrolyte solution. The experiment run time was 24h for each couple. The common potential, galvanic current and current integration during the last 6h were recorded for each couple.
The results showed that the best couples were Ti/Pontallor-4, Ti/Ter Ti, Ti/R800 and Ti/Jelstar. The least acceptable couples were Ti/amalgam, SSTi/SSTi and Ti/R2000, while the Ti/RCS couple showed unstable galvanic corrosion behavior.
It is concluded that the following alloys can be used as suprastructure alloys with Ti implants: Pontallor-4, R800, Jelstar and Ter Ti. Although Ter Ti alloy is an experimental alloy, it showed good results, but cannot be used in the clinical field unless extensive investigations are carried out. The SSTi/SSTi couple showed unexpected galvanic corrosion behavior which needs further investigation.
... The individual exhibited a fixed dental-supported rehabilitation ( Fig. 1): the maxilla presented a twelve-unit bridge supported by 5 teeth (FDI 12,15,23,24,and 25) and the mandible a four-unit bridge supported by 2 teeth (FDI 42 and 43), both metal-acrylic. The gold colouring of metal differentiated this case from the remaining fixed prostheses, and a classification of a gold-palladium (Au-Pd) alloy was obtained by comparison with what is applied in Portuguese dental practice nowadays. ...
... The preliminary assessment of the alloy was a gold and palladium composition, due to the gold tone of the device. These two elements are documented to be highly resistant to corrosion, and their biocompatibility makes them a good option for oral rehabilitations [24][25][26]. When observing the results of the elemental analyses, there was no evidence of these two elements. ...
Access to better health care anticipates that more medical devices can be found alongside skeletal remains. Those employed in oral rehabilitation, with available brands or batch/series, can prove useful in the identification process. A previous study in the Colecção de Esqueletos Identificados Século XXI described macroscopically the dental prostheses. An unusual case of a dental device with chromatic alterations demonstrated to require a more detailed analysis. The individual, a 53-year-old male, exhibited, at both arches, a fixed tooth-supported rehabilitation, with gold colouring classified initially as a gold-palladium alloy. Simultaneously, a green pigmentation deposit was observable in bone and prosthesis. This investigation aimed to verify the elemental composition of the dental prosthesis alloy. Elemental analysis was performed by X-ray fluorescence in two regions (labial surface of the prosthetic crown and the root surface of the lower right lateral incisor). Both the spectra and the qualitative results found higher levels of copper and aluminium, followed by nickel, iron, zinc, and manganese. No gold or palladium was detected. The most probable assumption is that a copper-aluminium alloy was used, as its elemental concentration corresponds to those measured in similar devices. Dental prostheses of copper-aluminium alloys have been made popular since the 1980s, particularly in the USA, Japan, and Eastern Europe. Apart from the biographical information, it was also known that the individual’s place of birth was an Eastern European country, which highlighted the usefulness of this type of information when dealing with missing people cases.
... Diferentes materiais metálicos são utilizados como biomateriais. O material mais utilizado em implantes dentários é o titânio e suas ligas devido às suas excelentes propriedades mecânicas, biocompatibilidade fisiológica e resistência à corrosão [1]. ...
... Quando o titânio é exposto à atmosfera, é rapidamente oxidado, formando uma camada de óxido passiva sobre a sua superfície. Esta camada de óxido determina as propriedades químicas, a resistência à corrosão e a química de interface do metal [1]. ...
O titânio e suas ligas são os materiais mais utilizados em implantes dentários devido às suas excelentes
propriedades mecânicas, biocompatibilidade e resistência à corrosão. O titânio quando exposto à atmosfera
oxidante formam uma camada de óxido passiva em sua superfície. Essa camada de óxido determina as
propriedades químicas e a resistência à corrosão do metal. O ambiente oral é particularmente propício à
corrosão. A corrosão galvânica ocorre quando ligas diferentes são colocadas em contato direto dentro dos tecidos ou cavidade oral. A deterioração de materiais metálicos tem efeitos desfavoráveis ao organismo, pois
aumenta a liberação de íons metálicos prejudiciais à saúde, além de comprometer a durabilidade dos materiais
e resultar em falhas dos implantes. O exemplo mais frequente de corrosão galvânica no meio oral é a interação
do implante dentário com o componente protético (abutment). Os pilares protéticos conectam a coroa aos
implantes e são fabricados com diferentes ligas, como CoCr, NiCr, CoCrMo e Ti-6Al-4V. Essa pesquisa teve
por objetivo analisar a resistência à corrosão galvânica do titânio comercialmente puro (TiG4 ASTM F67)
usado em implantes dentários em contato com as ligas CoCr (ASTM F1537) e Ti-6Al-4V (ASTM F136) usadas
como componentes protéticos das próteses implantossuportadas. Fez-se a medida de potencial de circuito
aberto e amperometria de resistência zero. Como eletrólito foi utilizada a solução NaCl 0,9%. Os resultados
obtidos mostraram que o uso dessas ligas em NaCl 0,9% não apresentaram geração de corrente galvânica.
... As an example, CuMn60, if slowly cooled post casting, would phase separate into both a pure Mn phase and a Cu-rich phase, 56 and a galvanic cell formed between the Cu rich phase and the Mn phase may lead to selective etching of the Mn one only. 57 In the case of Cu-Zn alloys fabricated by casting and rolling, the morphologies of the metal dendrites across the alloy formed during recrystallization will be greatly altered by the rolling process. These dendrites will be simultaneously fractionated and reoriented upon applying mechanical stress during rolling, greatly decreasing the average size of the dendrites and leading to many finely oriented grains. ...
... Thus when dental metal is placed in the mouth, it must withstand environmental pH changes. Taher and Al Jabab [3] investigated the Cavani corrosion between implants and crowns in artificial saliva with a pH of 7.2 and reported that Ni-Cr alloys and titanium alloys produced relatively unstable galvanic corrosion. Therefore, this study used electrochemical experiments to measure the potential difference between the corrosion phenomena of dental alloys and titanium alloys in artificial saliva with different pH values. ...
The purpose of this study was to investigate the corrosion behavior of four different dental casting alloys in artificial saliva solutions with varying pH values. Microstructures were observed using scanning electron microscopy. The corrosion behavior of the experimental alloys in artificial saliva was examined using potentiodynamic polarization measurements. The high noble alloy (Au-8.5Pt-2.6Pd-1.4In) exhibited better corrosion resistance with lower anodic current densities in the pH range of 3–5. The anodic current density of the noble alloy (Au-24.9Pd-19.0Ag-5.5In) decreased as the pH decreased. The noble (Pd-37.7Ag-8.5Sn) and base metal (Ni-25Cr-11.5Mo-1.4Si) alloys exhibited lower corrosion resistance with a relatively high current density at pH 3. Compared with noble alloys, base metal alloys exhibited good corrosion resistance in this study. This makes them a promising material for dental castings considering the complex pH changes in the oral environment.
... It is observed that for Tie6Ale4V F136 and Tie6Ale4V SLM ground, the potential overtime changes to more positive values than for the samples Tie6Ale4V SLM Fig. 9 e Chronoamperometry of the analyzed surfaces using 0.9% NaCl þ200 ppm of fluorine at pH 3 at two different potentials (a) 0.5 V and (b) 2 V. j o u r n a l o f m a t e r i a l s r e s e a r c h a n d t e c h n o l o g y 2 0 2 2 ; 2 1 : 3 8 4 4 e3 8 5 5 H 2 SO 4 þ HCl and Tie6Ale4V SLM HF. Both alloys have high corrosion resistance, and this positive potential is related to the formation of a passive film on the surface, which after some time tends to isolate the reactions between the materials [31]. The potential for these other conditions has a small reduction. ...
Ti-6Al-4V alloy (ASTM F136) is the Ti alloy mainly used for machined dental and orthopedic implants. Additive manufacturing (AM) or additive layer manufacturing (ALM) is the industrial process name for 3D printing. The AM include some processes among them selective laser melting (SLM), and electron beam melting (EBM). The AM is used to make products with complex and customized geometries. However, these techniques have limitations in terms of surface finishing quality. Implants produced by AM have high roughness and the presence of partially unfused particles on the surface which decreases the reactions among the device and cells and proteins in the body environment. The objective of the present work is to compare the surface morphologies and corrosion resistance of machined and SLM Ti-6Al-4V samples before and after acid etching. The surface characterization was performed using scanning electron microscopy (SEM) and optical profilometry. The corrosion resistance was analyzed using open circuit potential (OCP), potentiodynamic polarization, chronoamperometry, and zero resistance amperometry. Galvanic corrosion of Ti-6Al-4V in contact with Co-Cr-Mo alloys was analyzed. The results showed that the presence of unfused particles on the Ti-6Al-4V SLM sample surface decreased the corrosion resistance. The hydrofluoric acid (HF) surface etching increased the corrosion resistance of the SLM samples. Ti-6Al-4V SLM treated with HF solution for 20 min showed the highest corrosion resistance and lowest roughness surface. After sanding, both machined and SLM Ti-6Al-4V samples showed similar corrosion resistance in the 0.9% NaCl electrolyte with and without fluoride.
... The galvanic current depends on the potential differences between dental alloys. According to the multiple in vitro studies, significant galvanic current may occur in the following galvanic couples: dental amalgam and cobalt-chromium alloy [93,94]; titanium alloy and dental amalgam [95]; nitinol archwire and titanium brackets [96]; nitinol archwire and iron brackets [96,97]; titanium dental implant and cobalt-chromium or nickel-chromium alloys [98][99][100][101]. Moreover, the surface area of metallic appliances should be taken into account. ...
Metal alloys are one of the most popular materials used in current dental practice. In the oral cavity, metal structures are exposed to various mechanical and chemical factors. Consequently, metal ions are released into the oral fluid, which may negatively affect the surrounding tissues and even internal organs. Adverse effects associated with metallic oral appliances may have various local and systemic manifestations, such as mouth burning, potentially malignant oral lesions, and local or systemic hypersensitivity. However, clear diagnostic criteria and treatment guidelines for adverse effects associated with dental alloys have not been developed yet. The present comprehensive literature review aims (1) to summarize the current information related to possible side effects of metallic oral appliances; (2) to analyze the risk factors aggravating the negative effects of dental alloys; and (3) to develop recommendations for diagnosis, management, and prevention of pathological conditions associated with metallic oral appliances.
... Amal A.EL Sawy 2013 [45] evaluated the metal ion release from titanium and co-cr-mo casting alloys, showed there was increase in ion concentration of different elements for both alloys, and most released ions was cobalt and less one was titanium but not agree with Taher NM, Al Jabab AS 2013. [46] studied Galvanic corrosion behavior of implant suprastructure dental alloys and reported that the titanium was found to be more corrosion than cobalt chromium alloys in connected to titanium implant .this conflict may be due to the titanium used in this study was anodizing type which more stable than non anodizing one accordance to Abdullah Afshar et.al 2011 [47] founded the corrosion rate in non-anodizing state is much higher than that in anodized one due to the resistant anodic film on surface on anodized titanium. ...
... A study by Arismendi et al. suggests that the best restorationimplant pairing can be achieved by using cp titanium and a titanium alloy [8]. Whereas Taher et al. suggest that the best couples are Ti/Ti, Ti/Or, and Ti/CoCr [15]. ...
Purpose:
The objective of this work is to study galvanic corrosion of different couples of prosthetic and implant alloys through the realization of a systematic review.
Materials and methods:
An electronic search was performed on Pubmed, Google Scholar, Scopus, ScienceDirect, EbscoHost, and Web of Science for published studies related to electrogalvanism in oral implantology. The keywords used were "dental implants" and "galvanic corrosion." Two independent readers read the scientific articles.
Results:
From 65 articles initially identified, only 19 articles met the eligibility criteria. The evaluation of the selected articles allowed us to determine the parameters compared, such as the resistance to galvanic corrosion, the influence of fluorine and pH on the electrochemical behavior, and the release of metal ions and their cytotoxicity. Indeed, Ti6Al4V and precious alloys coupled to titanium were found to be the most resistant to galvanic corrosion, followed by cobalt-chromium alloys and nickel-chromium alloys which were least resistant. This resistance decreases with increasing fluorine concentration and with decreasing pH of the environment. Discussion. The implant-prosthetic system's galvanic resistance is influenced by many intrinsic factors: alloy composition and surface condition, as well as extrinsic factors such as pH variations and amount of fluorine. The effects of oral electrogalvanism are essentially the result of two main criteria: effects due to electric currents generated by corrosion and effects due to the release of metal ions by corrosion.
Conclusion:
To avoid this phenomenon, it is wise to follow the proposed recommendations such as the use of the minimum of distinct metals as much as possible, favoring the commercially pure titanium implant of Ti6Al4V, opting for the choice of couples, titanium/titanium, favoring daily mouthwashes of 227 ppm of fluoride, and avoiding fluorinated acid solutions.
... Metal elements in the body remain in contact with the bodily fluids, which are electrolytic in character, and so they undergo corrosion. This process causes, on the one hand, their destruction, and on the other hand, release of corrosion products and metal ions into the surrounding tissue, which, in many cases, has a very disadvantageous effect on the body [1][2][3][4][5][6][7]. Metal elements made of non-precious metals are at present quite broadly used in dental prosthetics and orthodontics. ...
Background: Investigating the general corrosion resistance of Ti(C,N) type coatings on a prosthetic nickel alloy in the aspect of their use as protective coatings on prosthetic and orthodontic elements. Methods: Five groups of Ni-Cr alloy samples covered with Ti(C,N) type coatings differing in their carbon and nitrogen contents were used for the tests. The reference group included alloy samples without coatings. The samples were held for 105 days (2520 h) in salt spray chambers and examined by means of the NSS (neutral salt spray) and SWAAT (sea water acetic acid test) tests. After the periods of 14, 28, 81 and 105 days, the samples were removed and weighed, and their weight losses were determined. Results: In the case of each type of Ti(C,N) coating, the mass loss was lower than the mass loss of a sample without a coating, which makes it possible to state that coatings improve the corrosion resistance. No significant differences in the resistance were observed between the particular coatings. The corrosion rate of the examined coatings is close to parabolic. Conclusions: Ti(C,N) type coatings improve the resistance of a prosthetic Ni-Cr alloy and can be used as protective coatings for prosthetic and orthodontic elements.
The aim of this work was to investigate the effect of galvanic coupling between stainless steel AISI 316 L abutment type Morse taper and implant made of ASTM F1108-14 Ti-6Al-4V alloy. The assembly of the two alloys was carried out using mechanical imbrication by means of successive strikes at 0.05 J force onto the abutment inserted in the implant along the centerline. Corrosion attack at the interface of the alloys was evaluated according to the number of strikes used for joining the parts. Corrosion resistance was evaluated for the samples by open circuit potential measurements as function of time and scanning vibrating electrode technique (SVET) and scanning ion selective electrode technique (SIET) in phosphate buffer solution with pH adjusted to 3.0, and into which hydrogen peroxide was added to simulate tissue inflammatory conditions. Samples were evaluated at the cross and longitudinal sections. Results indicated that the number of strikes used in assembling affected corrosion susceptibility. The lowest amount of corrosion products was associated to the highest number of strikes used. The corrosion resistance was related to the characteristics of the crevice between the implant and the abutment.
Metallic materials utilized for the construction of intra-oral and implant dental restorations include a wide range of relatively pure metals and multicomponent alloys. Basic corrosion and biodegradation properties of these alloys have been studied by both in vitro and in vivo techniques. These property characteristics have been shown to be dependent on composition and metallurgical state, combinations within a construct, surface conditions, mechanical aspects of function, and the local and systemic host environment. The susceptibility of these metallic materials to various forms of biodegradation will be presented, with emphasis on corrosion.
Sixty-six consecutive patients treated at the Prosthodontic Clinic in Uppsala, Sweden, received implant-supported fixed prostheses of the Brånemark type. The prosthesis frameworks were made of cobalt-chromium alloys. Different techniques for attaching the gold cylinders to the frameworks were used. Mechanical attachment with autopolymerizing polymethyl methacrylate resin (PMMA), partial soldering combined with PMMA attachment, and soldering only were used. No abnormal tissue reactions were seen. Radiographic examination of the implants was performed at the time of prosthesis placement and at the 1- and 3-year follow-up visits. A few cases of minor bone loss were detected but not related to the materials used in the superstructures.
Abstract – The galvanic current densities between gold, amalgam and cobalt-chromium, three different classes of dental alloys, were determined in vitro in artificial saliva kept at 35°C. The maximum current density of 200 μA/drn2was obtained between the conventional amalgam and a type III gold alloy. Galvanic currents of lesser magnitude could also be measured between amalgams high in copper and the other alloys. No measurable current densities were obtained between gold alloys and between gold and cobalt-chromium alloy with the exception of a casting and a solder gold alloy commonly used in combination.
Sixty-six consecutive patients treated at the Prosthodontic Clinic in Uppsala, Sweden, received implant-supported fixed prostheses of the Brånemark type. The prosthesis frameworks were made of cobalt-chromium alloys. Different techniques for attaching the gold cylinders to the frameworks were used. Mechanical attachment with self-curing polymethyl methacrylate (PMMA), partial soldering combined with PMMA attachment, and soldering only were used. No abnormal tissue reactions were seen. Radiographic examination of the fixtures was performed at the time of prosthesis placement and at the 1- and 3-year follow-ups. A few cases of minor bone loss were detected but not related to the materials used in the superstructures.
The corrosion of two materials for implant supraconstructions, a carbon fiber/PMMA composite and a silver-palladium alloy, was investigated in vitro, the materials being galvanically coupled to a titanium implant. Corrosion current and pH of the electrolyte were monitored, and corrosion products were identified by powder X-ray diffraction. The carbon composite and the silver-palladium per se did not corrode, whereas a silver-palladium specimen brazed with the recommended brazing alloy corroded unmistakably, yielding copper-containing corrosion products. The action of local corrosion cells around the brazed joint is considered, and it is concluded that the two materials seem well suited for implant supraconstructions, provided that brazing the silver-palladium can be avoided. Considering the clinical relevance of the experimental model used, it is concluded that the model is likely to predict a lower corrosion susceptibility than the one found in vivo.
Electron spectroscopy and argon ion etching were used to determine the depth and composition of the oxide layers of six competitive dental implant systems. To minimize problems associated with analyzing the active oxide layers, the implants were removed from their original packaging in an oxygen-free environment. The majority of the six implant systems were found to have similar oxide thickness in the range of 20 to 34 A. Some variation was found in the extent of non-oxide surface contamination.
To characterize the galvanic corrosion of supraconstructions consisting of Ni-Cr alloys that come in contact with titanium implants, the resultant substance loss was determined. The measurement of the released substance masses was conducted by analysis of the electrolyte solutions with the aid of atomic absorption spectrometry and by approximate calculation using current density time curves, according to Faraday's law. The results of this study show that both methods allow a clear differentiation of the corrosion behavior of various Ni-Cr alloys that come in contact with titanium.
Corrosion reactions around titanium, usually considered biologically inert, might be provoked by coupling it galvanically with more corrodible dental alloys. Experiments in vitro simulating the conditions of a titanium dental implant or root canal post coupled to an amalgam filling, demonstrated corrosion current densities up to 31 microA/cm2, anodic pH values around the amalgam down to 2, and cathodic pH values around the titanium up to 10. The amounts of tin released by the enhanced corrosion of amalgam might contribute measurably to the daily intake of this element; the corrosion current generated reached values known to cause taste sensations. If the buffer systems of adjacent tissues in vivo are not able to cope with the high pH generated around the titanium, local tissue damage may ensue; this relationship is liable to be overlooked, as it leaves no evidence in the form of corrosion products.