Ion Release Tests Research Articles

Albumin suppresses oxidation of TiNb alloy in the simulated inflammatory environment.

Literature data has shown that reactive oxygen species (ROS), generated by immune cells during post-operative inflammation, could induce corrosion of standard Ti-based biomaterials. For Ti6Al4V alloy, this process can be further accelerated by the presence of albumin. However, this phenomenon remains unexplored for Ti β-phase materials, such as TiNb alloys. These alloys are attractive due to their relatively low elastic modulus value. This study aims to address the question of how albumin influences the corrosion resistance of TiNb alloy under simulated inflammation. Electrochemical and ion release tests have revealed that albumin significantly enhances corrosion resistance over both short (2 and 24 h) and long (2 weeks) exposure periods. Furthermore, post-immersion XPS and cross-section TEM analysis have demonstrated that prolonged exposure to an albumin-rich inflammatory solution results in the complete coverage of the TiNb surface by a protein layer. Moreover, TEM studies revealed that H2O2-induced oxidation and further formation of a defective oxide film were suppressed in the solution enriched with albumin. Overall results indicate that contrary to Ti6Al4V, the addition of albumin to the PBS + H2O2 solution is not necessary to simulate the harsh inflammatory conditions as could possibly be found in the vicinity of a TiNb implant.

The Potential Of Avocado Seed Extract (Persea Americana) In Inhibiting The Release Of Metal Ions In Cuniti And Stainless Steel Based Orthodont Wire

The release of ions is the initial stage of the corrosion process in an orthodontic wire. Continuous release of ions can reduce the effectiveness and performance of the orthodontic wire. Continuous release of ions in CuNiTi orthodontic wire can change the properties of the wire and trigger hypersensitivity reactions, also in stainless steel orthodontic wire which experiences continuous release of ions can reduce its stiffness. The tannin in avocado seeds is useful as a corrosion inhibitor it can inhibit the release of ions because they are able to bind with metal ions and form a passive layer also able to bind with Fe ions in stainless steel orthodontic wires to form a passive surface layer which is able to inhibit the release of ions when the corrosion process occurs. The aim of this research is to determine the effect of avocado seed extract as a corrosion inhibitor on the release of metal ions from CuNiTi and stainless steel orthodontic wires. Rectangular CuNiTi and stainless steel orthodontic wires measuring 0.017 x 0.025 inches were taken in 3 groups (1 control group soaked in artificial saliva and 2 treatment groups soaked in avocado seed extract). The samples were soaked in avocado seed extract with a concentration of 1.5 g/L and 2 g/L for 7 days. To see the release of ions, an X-Ray Fluorescence test is carried out. In CuNiTi orthodontic wire from the one way ANOVA test showed that there was a significant difference between the control group and all treatment groups on Cu, Ni and Ti ions. The Post Hoc LSD test showed that there were significant differences between the control group, treatment group 1 and treatment group 2 in Cu, Ni and Ti ions with a p value. In stainless steel orthodontic wire, the one way ANOVA test showed that there was a significant difference between the control group and all treatment groups in Fe and Ni ions but not significant in Cr ions in the ion release test with a p value <0.05. The Post Hoc LSD test showed that there were significant differences between the control group, treatment group 1 and treatment group 2 in Fe and Ni ions with a p value <0.05. Providing avocado seed extract with tannin content at concentrations of 1.5 g/L and 2 g/L can inhibit the rate of ion release in CuNiTi and stainless steel orthodontic wires due to the corrosion process.

Antimicrobial Properties of Ion-Modified Zeolite Composites: A Study on Biofilm Inhibition and Bacterial Cell Viability

This work investigates the antibacterial efficacy of zeolite composites by using combinations of zinc, manganese, and magnesium ions at concentrations of 1%, 2%, 3%, and 4%. Our assessment of the antibacterial effectiveness was conducted by biofilm inhibition, insitu bacterial colonization, and ion-release tests. The results indicated that the liberation of zinc ions increased from 1.5 parts per million (ppm) at a concentration of 1% to 6.0 ppm at a concentration of 4%. Furthermore, the liberation of manganese ions varied between 2.0 ppm and 6.7 ppm, whereas that of magnesium ions ranged from 1.8 ppm to 5.5 ppm. The biofilm inhibition, as shown by OD570 values, decreased dramatically from 0.85 at 1% to 0.40 at a concentration of 4%. Bacterial viability tests revealed that at a 1% ion concentration, the proportion of damaged cells rose to 60%, while the proportion of viable cells decreased from 70% to 40%. Furthermore, these results indicate that higher ion concentration amplifies the antibacterial activity of the composites, making them very efficient in inhibiting biofilms and deactivating microorganisms. Conclusions of the research suggest that ion-modified zeolite composites might be advantageous for antimicrobial applications in various environments prone to microbial contamination.

A Comparative Study on Physicochemical Properties and In Vitro Biocompatibility of Sr-Substituted and Sr Ranelate-Loaded Hydroxyapatite Nanoparticles.

Synthetic hydroxyapatite nanoparticles (nHAp) possess compositional and structural similarities to those of bone minerals and play a key role in bone regenerative medicine. Functionalization of calcium phosphate biomaterials with Sr, i.e., bone extracellular matrix trace element, has been proven to be an effective biomaterial-based strategy for promoting osteogenesis in vitro and in vivo. Functionalizing nHAp with Sr2+ ions or strontium ranelate (SrRAN) can provide favorable bone tissue regeneration by locally delivering bioactive molecules to the bone defect microenvironment. Moreover, administering an antiosteoporotic drug, SrRAN, directly into site-specific bone defects could significantly reduce the necessary drug dosage and the risk of possible side effects. Our study evaluated the impact of the Sr source (Sr2+ ions and SrRAN) used to functionalize nHAp by wet precipitation on its in vitro cellular activities. The systematic comparison of physicochemical properties, in vitro Sr2+ and Ca2+ ion release, and their effect on in vitro cellular activities of the developed Sr-functionalized nHAp was performed. The ion release tests in TRIS-HCl demonstrated a 21-day slow and continuous release of the Sr2+ and Ca2+ ions from both Sr-substituted nHAp and SrRAN-loaded HAp. Also, SrRAN and Sr2+ ion release kinetics were evaluated in DMEM to understand their correlation with in vitro cellular effects in the same time frame. Relatively low concentration (up to 2 wt %) of Sr in the nHAp led to an increase in the alkaline phosphatase activity in preosteoblasts and expression of collagen I and osteocalcin in osteoblasts, demonstrating their ability to boost bone formation.

PLLA Nanosheets for Wound Healing: Embedding with Iron-Ion-Containing Nanoparticles

This article reports on polymer (PLLA, poly(L-lactic acid)) nanosheets incorporated with Fe-ion nanoparticles, aiming at using the latter nanoparticles as a source to release Fe ions. Such Fe ions should facilitate burn wound healing when such nanosheets are applied as a biomedical tissue on skin. Laser ablation in liquid phase was used to produce Fe-containing nanoparticles that, after incorporation into PLLA nanosheets, would release Fe ions upon immersion in water. Unlike most iron-oxide nanostructures, which are poorly soluble, such nanoparticles prepared in chloroform were found to have water solubility, as they were shown by XPS to be based on iron chloride and oxide phases. After incorporation into PLLA nanosheets, the ion-release test demonstrated that Fe ions could be released successfully into water at pH 7.4. Incorporation with two different metal ions (Fe and Zn) was also found to be efficient, as both types of ions were demonstrated to be released simultaneously and with comparable release rates. The results imply that such polymer nanosheets show promise for biomedical applications as potential patches for healing of burns.

Calcination and ion substitution improve physicochemical and biological properties of nanohydroxyapatite for bone tissue engineering applications

Nanohydroxyapatite (nanoHAP) is widely used in bone regeneration, but there is a need to enhance its properties to provide stimuli for cell commitment and osteoconduction. This study examines the effect of calcination at 1200 °C on the physicochemical and biological properties of nanoHAP doped with magnesium (Mg2+), strontium (Sr2+), and zinc (Zn2+). A synergistic effect of dual modification on nanoHAP biological properties was investigated. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), BET analysis, Fourier-transform spectroscopy, and thermal analysis methods. Furthermore, ion release tests and in vitro biological characterization, including cytocompatibility, reactive oxygen species production, osteoconductive potential and cell proliferation, were performed. The XRD results indicate that the ion substitution of nanoHAP has no effect on the apatite structure, and after calcination, β-tricalcium phosphate (β-TCP) is formed as an additional phase. SEM analysis showed that calcination induces the agglomeration of particles and changes in surface morphology. A decrease in the specific surface area and in the ion release rate was observed. Combining calcination and nanoHAP ion modification is beneficial for cell proliferation and osteoblast response and provide additional stimuli for cell commitment in bone regeneration.

Ionic release of dental cobalt-chromium based alloys

Background: Since the 1980s, as the cost of noble metals has increased, more base metal alloys have been used in fixed and removable prostheses. Cobalt-chromium (Co-Cr) alloys are one of the most widely used base metal alloys in the prosthetic dental department and have several clinical uses. Co-Cr alloys are frequently used as having excellent biocompatibility, great strength, good resistance to tarnish, corrosion, and wear, as well as being heat-resistant and non-magnetic.
 Materials and Methods: For the ion release test, seventy specimens of a cobalt-chrome alloy disc with dimensions of 5 mm in diameter and 3 mm in thickness were created. They were divided into five groups, each of which had 14 specimens, based on the manufacturing method as follows: new cast alloy group; selective laser melting group (3D printer specimens); once recast alloy + old selective laser melting group; new cast + once recast alloy group; once recast alloy group.
 Result: The outcomes showed that there were no
 statistically significant differences in ion release in any of the groups examined (P>0.05).
 Conclusion: The production technique and alloy composition have a slight influence on ion release. A positive clinical response is anticipated, since it was found that every group met the ionic release criteria of the international standards.

Development of a Surface Treatment to Achieve Long-Lasting Antimicrobial Properties and Non-Cytotoxicity through Simultaneous Incorporation of Ag and Zn via Two-Step Micro-Arc Oxidation

A customized micro-arc oxidation (MAO) treatment technique was developed to obtain antibacterial properties with no toxicity on Ti surfaces. A two-step MAO treatment was used to fabricate a specimen containing both Ag and Zn in its surface oxide layer, and the optimal incorporation conditions were determined. Surface characterization by EDS was performed followed by the antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) and osteogenic cell compatibility evaluations. In addition, metal ion release tests were performed to evaluate the contents of Ag and Zn and the ion release behavior in order to simulate practical usage. MAO-treated specimens prepared using proper concentrations of Ag and Zn (0.5Ag-5Zn: 0.5 mM AgNO3 and 5.0 mM ZnCl, respectively) exhibited excellent antibacterial properties against E. coli and S. aureus and no toxicity to MC3T3-E1 in antibacterial and cytotoxic evaluations, respectively. The antibacterial property of 0.5Ag-5Zn against S. aureus was sustained even after two months of immersion in physiological saline, simulating the in vivo environment.

Differences between 3-D printed and traditionally milled CoCr dental alloy from casted block in oral environment

The aim of this study was to compare corrosion resistance and ion release in CoCr dental alloys with identical chemical compositions produced using different technologies (SLM – selective laser melting and milling from cast blocks) and heat treatment (SLM parts only). The corrosion properties were tested in artificial saliva, artificial saliva with fluoride ions, and artificial saliva with added lactic acid to simulate inflammations. The study included electrochemical tests, microstructural investigation and ion release tests in the three different environments for a total of 42 days. The best performance of CoCr as a result of potentiodynamic polarization was observed in the artificial saliva with added lactic acid, which is in contradiction with the highest ion release measured from all the materials tested and electrochemical impedance spectroscopy that showed a deterioration of the passive layer in an acidic environment. Microstructural investigation revealed that different phases precipitated by heat treatment trigger increased release of Mo and W ions. The printing method does not raise critically ion release from CoCr alloy, while the state of the surface greatly impacts the extent of the ion release. This study demonstrates the importance of an interdisciplinary approach to the study of corrosion and biocompatibility in dental alloys.

Study of physico-mechanical and electrical properties of cerium doped hydroxyapatite for biomedical applications

The hydroxyapatite-based cerium-doped ceramics (Ce-HAp) were synthesized by the wet precipitation method. The mechanical and dielectric properties were investigated by density, microhardness, and impedance spectroscopy techniques. XRD and FTIR techniques were used to study the crystal structure of synthesized ceramics. ICP-OES and EDX results showed the elemental composition of doped Ce ions in the Ce-HAp samples. SEM results showed the rod-like morphology for 1.5 wt% Ce doped powders. Powders of varying Ce concentrations were molded into scaffolds and subjected to sintering at 1250 °C. The density, microhardness, and tensile strength results showed enhanced mechanical properties up to 1.5 wt% Ce which decreased with a further increase in Ce concentration. The impedance results showed better electrical network formation, increased conductivity, and diminished resistances in Ce-doped samples which suggest the usefulness of the composite for better bone healing, regeneration, and bone growth. The standard ion release test showed no leaching of Ce, H+, and OH− ions from fabricated solid pellets even after 22 days of immersion in simulated body fluid. These results indicate the excellent doping potential of Ce ions in hydroxyapatite-based ceramics for biomedical applications.

Facile Electrochemical Preparation of Hydrophobic Antibacterial Fabrics Using Reduced Graphene Oxide/Silver Nanoparticles

AbstractA novel facile electrochemical method was developed for in situ coating of fabrics with reduced graphene oxide/silver nanoparticles. The procedure consisted of three steps: spray coating of graphene oxide on the fabric, electrochemical reduction of the graphene oxide layer, and electrodeposition of silver nanoparticles on the fabrics. All the steps were performed at room temperature without using a toxic reducing agent. The fabrics coated with reduced graphene oxide/silver nanoparticles demonstrated excellent hydrophobicity (water contact angle of 148.0°±1.1) and strong antibacterial activity against gram‐negative Escherichia coli bacteria (reduction rate >99.99 %). The durability of the modified fabrics was investigated by a washing experiment. Based on the results of this test, the reduction rate of the fabric did not decrease after 60 washing times. The results of the silver ion release test revealed a slow leaching rate from the fabric which confirms the long‐term antibacterial activity of the fabrics.

Comparative study on trichloroethylene degradation enhanced by three organic acid chelating agents in sodium percarbonate/Fe(II) system in the presence of surfactant

Based on a few studies on the effect of different chelators on the Fenton system in a solution containing surfactants, sodium dodecyl sulfate (SDS) was selected as an exemplary surfactant to conduct a comparative study on trichloroethylene (TCE) degradation of Fe(II) catalyzed sodium percarbonate (SPC) system by citric acid (CA), oxalic acid (OA), and glutamic acid (GA) chelating agents, respectively. All these three chelators could relieve the inhibition of SDS on TCE removal. Due to the existence of SDS, GA had the most significant promoting effect on TCE degradation. According to Fe(II) concentration and the decomposition of chelators, it was proved that GA system combined with SDS could maintain the highest Fe(II) content and accelerate the formation of hydroxyl radical (HO•). Probe, scavenging, and EPR experiments demonstrated that SPC/chelated-Fe(II) systems produced more HO•. The hysteresis of the dechlorination process was found in the chloride ion release test, certifying that the degradation process of TCE in chelating systems was complicated. Through solution matrixes and actual groundwater experiments, the chelating systems could broaden the scope of pH application, reduce the influence of inorganic ions, and have a good practical application prospect.

A biomechanical evaluation on Cubic, Octet, and TPMS gyroid Ti6Al4V lattice structures fabricated by selective laser melting and the effects of their debris on human osteoblast-like cells.

Lattice structures are widely used in orthopedic implants due to their unique features, such as high strength-to-weight ratios and adjustable biomechanical properties. Based on the type of unit cell geometry, lattice structures may be classified into two types: strut-based structures and sheet-based structures. In this study, strut-based structures (Cubic & Octet) and sheet-based structure (triply periodic minimal surface (TPMS) gyroid) were investigated. The biomechanical properties of the three different Ti6Al4V lattice structures fabricated by selective laser melting (SLM) were investigated using room temperature compression testing. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to check the 3D printing quality with regards to defects and quantitative compositional information of 3D printed parts. Experimental results indicated that TPMS gyroid has superior biomechanical properties when compared to Cubic and Octet. Also, TPMS gyroid was found to be less affected by the variations in relative density. The biocompatibility of Ti6Al4V lattice structures was validated through the cytotoxicity test with human osteoblast-like SAOS2 cells. The debris generated during the degradation process in the form of particles and ions is among the primary causes of implant failure over time. In this study, Ti6Al4V particles with spherical and irregular shapes having average particle sizes of 36.5μm and 28.8μm, respectively, were used to mimic the actual Ti6Al4V particles to understand their harmful effects better. Also, the effects and amount of Ti6Al4V ions released after immersion within the cell culture media were investigated using the indirect cytotoxicity test and ion release test.

Copper-doped cotton-like malleable electrospun bioactive glass fibers for wound healing applications

The combination of electrospinning and sol-gel methods is attracting the interest of the scientific community for developing three-dimensional bioactive glass (BG)-based fibers. This paper reports the fabrication of cotton-like copper-doped BG fibers by combining electrospinning and sol-gel techniques. Acellular bioactivity in simulated body fluid, ion release, cell viability and scratch cell tests were performed. Results showed that copper was successfully incorporated in the fibers and Cu ions were released in limited concentration over seven days. The presence of copper delayed the mineralization of the fibers upon immersion in simulated body fluid (SBF), but it did not affect keratinocyte viability and migration. Wound closure in the scratch cell test was achieved in 48 h for all the investigated samples.

Relevant Aspects of Piranha Passivation in Ti6Al4V Alloy Dental Meshes

Passivation of titanium alloy dental meshes cleans their surface and forms a thin layer of protective oxide (TiO2) on the surface of the material to improve resistance to corrosion and prevent release of ions to the physiological environment. The most common chemical agent for the passivation process of titanium meshes is hydrochloric acid (HCl). In this work, we introduce the use of Piranha solution (H2SO4 and H2O2) as a passivating and bactericidal agent for metallic dental meshes. Meshes of grade 5 titanium alloy (Ti6Al4V) were tested after different treatments: as-received control (Ctr), passivated by HCl, and passivated by Piranha solution. Physical-chemical characterization of all treated surfaces was carried out by scanning electron microscopy (SEM), confocal microscopy and sessile drop goniometry to assess meshes’ topography, elemental composition, roughness, wettability and surface free energy, that is, relevant properties with potential effects for the biological response of the material. Moreover, open circuit potential and potentiodynamic tests were carried out to evaluate the corrosion behavior of the differently-treated meshes under physiological conditions. Ion release tests were conducted using Inductively Coupled Plasma mass spectrometry (ICP-MS). The antibacterial activity by prevention of bacterial adhesion tests on the meshes was performed for two different bacterial strains, Pseudomonas aeruginosa (Gram-) and Streptococcus sanguinis (Gram+). Additionally, a bacterial viability study was performed with the LIVE/DEAD test. We complemented the antibacterial study by counting cells attached to the surface of the meshes visualized by SEM. Our results showed that the passivation of titanium meshes with Piranha solution improved their hydrophilicity and conferred a notably higher bactericidal activity in comparison with the meshes passivated with HCl. This unique response can be attributed to differences in the obtained nanotextures of the TiO2 layer. However, Piranha solution treatment decreased electrochemical stability and increased ion release as a result of the porous coating formed on the treated surfaces, which can compromise their corrosion resistance. Framed by the limitations of this work, we conclude that using Piranha solution is a viable alternative method for passivating titanium dental meshes with beneficial antibacterial properties that merits further validation for its translation as a treatment applied to clinically-used meshes.

Mechanical, Corrosion, and Ion Release Studies of Ti-34Nb-6Sn Alloy with Comparable to the Bone Elastic Modulus by Powder Metallurgy Method

The development of a Ti-34Nb-6Sn alloy by the powder metallurgy method, employing two different compaction conditions, A (100 MPa) and B (200 MPa), was carried out. To evaluate the feasibility of the Ti-34Nb-6Sn alloy as an implant biomaterial, microstructural and mechanical characterizations, as well as corrosion susceptibility and ion release tests, were performed. Results indicated microstructures dominated by the presence of β-Ti phase and a lower percentage of α-Ti and Nb phases. The porosity percentage decreased when the compaction pressure increased. Both conditions presented a good match between the elastic moduli of the alloy (14.0 to 18.8 GPa) and that reported for the bone tissue. The Ti, Nb and Sn ions released for both compaction conditions were within the acceptable ranges for the human body. Condition B showed higher corrosion resistance in comparison with condition A. Based on the obtained results, the produced porous Ti-34Nb-6Sn alloys are feasible materials for orthopedic implant applications.

Citric Acid in the Passivation of Titanium Dental Implants: Corrosion Resistance and Bactericide Behavior.

The passivation of titanium dental implants is performed in order to clean the surface and obtain a thin layer of protective oxide (TiO2) on the surface of the material in order to improve its behavior against corrosion and prevent the release of ions into the physiological environment. The most common chemical agent for the passivation process is hydrochloric acid (HCl), and in this work we intend to determine the capacity of citric acid as a passivating and bactericidal agent. Discs of commercially pure titanium (c.p.Ti) grade 4 were used with different treatments: control (Ctr), passivated by HCl, passivated by citric acid at 20% at different immersion times (20, 30, and 40 min) and a higher concentration of citric acid (40%) for 20 min. Physical-chemical characterization of all of the treated surfaces has been carried out by scanning electronic microscopy (SEM), confocal microscopy, and the ‘Sessile Drop’ technique in order to obtain information about different parameters (topography, elemental composition, roughness, wettability, and surface energy) that are relevant to understand the biological response of the material. In order to evaluate the corrosion behavior of the different treatments under physiological conditions, open circuit potential and potentiodynamic tests have been carried out. Additionally, ion release tests were realized by means of ICP-MS. The antibacterial behavior has been evaluated by performing bacterial adhesion tests, in which two strains have been used: Pseudomonas aeruginosa (Gram–) and Streptococcus sanguinis (Gram+). After the adhesion test, a bacterial viability study has been carried out (‘Life and Death’) and the number of colony-forming units has been calculated with SEM images. The results obtained show that the passivation with citric acid improves the hydrophilic character, corrosion resistance, and presents a bactericide character in comparison with the HCl treatment. The increasing of citric acid concentration improves the bactericide effect but decreases the corrosion resistance parameters. Ion release levels at high citric acid concentrations increase very significantly. The effect of the immersion times studied do not present an effect on the properties.

Zhe role of zirconia additions on the microstructure and corrosion behavior of Ni-Cr dental alloys

This study investigates the effect of zirconia addition with different percentages on Ni-Cr alloy using a powder metallurgy technique. The scanning electron microscope with energy dispersive spectroscopy is used to analyze the microstructure of Ni-Cr and Ni-Cr-x ZrO2 (where x is 3, 6, 9 wt.%) alloys. The x-ray diffraction method is used to determine the phases for Ni-Cr and Ni-Cr/ZrO2 alloys. The corrosion and ion release tests were also achieved using potentiodynamic polarization and atomic absorption spectroscopy. According to the microstructural investigation, the results found that the Ni-Cr alloy’s grain size tends to reduce with the addition of ZrO2 with obtaining the smallest grain size with 6 wt.% addition. The potentiodynamic polarization exhibited that the modified alloys are more resistant to corrosion in the saliva medium than the Ni-Cr alloy. Furthermore, the role of ZrO2 in dissolution test shows the development in the passive layer’s resistance compared to unmodified alloys with reducing the Ni release from 2.5 ppm to 0.2 ppm. It can conclude that the addition of ZrO2 has significantly improved Ni-Cr’s biocompatibility and extend the area of implementations.

Remarkable bactericidal traits of a metal-ceramic composite coating elated by hierarchically structured surface.

SummaryA ceramic-based coating with a hierarchical surface structure was synthesized via solid-state reaction enabled by a double cathode glow discharge technique. This innovative coating comprises two distinct layers, specifically an outer layer with a well-aligned micro-pillar array and a dense inner layer. Both are composed of a face-centered cubic Cu(Co,Ni,Fe) solid solution phase together with a spinel-type Fe(Al,Cr)2O4 oxide. This coating exhibits superhydrophobicity and, yet, a very strong adhesion to water, i.e., the so-called “rose petal effect”. This coating also exhibits highly efficient antibacterial ability against both Staphylococcus aureus and Escherichia coli bacteria under both dark and visible light conditions. The excellent antibacterial property originates from the synergistic effects through the release of Cu ions coupled with photothermal activity upon light activation.

Cobalt–chromium alloys fabricated with four different techniques: Ion release, toxicity of released elements and surface roughness

ObjectiveTo investigate the metal ion release, surface roughness and cytoxicity for Co–Cr alloys produced by different manufacturing techniques before and after heat treatment. In addition, to evaluate if the combination of materials affects the ion release. MethodsFive Co–Cr alloys were included, based on four manufacturing techniques. Commercially pure titanium, CpTi grade 4 and a titanium alloy were included for comparison. The ion release tests involved both Inductive Coupled Plasma Optical Emission Spectrometry and Inductive Coupled Plasma Mass Spectrometry analyses. The surface analysis was conducted with optical interferometry. Cells were indirectly exposed to the materials and cell viability was evaluated with the MTT (3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide) method. ResultsAll alloys showed a decrease of the total ion release when CpTi grade 4 was present. The total ion release decreased over time for all specimens and the highest ion release was observed from the cast and milled Co–Cr alloy in acidic conditions.The cast and laser-melted Co–Cr alloy and the titanium alloy became rougher after heat treatment. All materials were within the limits of cell viability according to standards. SignificanceThe ion release from Co–Cr alloys is influenced by the combination of materials, pH and time. Surface roughness is influenced by heat treatment. Furthermore, both ion release and surface roughness are influenced by the manufacturing technique and the alloy type. The clinical implication needs to be further investigated.