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This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives – niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-β-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy. [ABSTRACT FROM AUTHOR]

This work reports on determination of the influence of passivation type of Ti15wt.%Mo implant alloy surface on its corrosion resistance in simulated body fluids. The alloy under investigation was subjected to natural self-passivation in air, and forced passivation by autoclaving in steam, boiling in 30 % solution of H2O2, and electrochemical passivation in 0.9 % NaCl solution. Resistance of the passivated Ti15Mo alloy to pitting corrosion was studied at 37ºC in 0.9 % NaCl solution using open circuit potential method, anodic polarization curves, and electrochemical impedance spectroscopy (EIS). Comparative estimation of the determined parameters of corrosion resistance revealed that the obtained passive layers improve anticorrosive properties of the tested alloy. Surface of the alloy subjected to passivation in steam autoclave reveals the highest protection against pitting corrosion. Anodic potentiodynamic curves showed that the Ti15Mo alloy after different passivation types of the surface is characterized by a lack of susceptibility to pitting corrosion up to potential of 9 V. Based on the EIS investigations, the thickness of the formed oxide layers (TiO2, anatase) was determined to be in the range from 2.0 to 7.8 nm in dependence on the applied type of passivation. It was ascertained that electrochemical properties of the Ti15Mo alloy and possibility of its surface passivation using simple methods, make it an attractive material for use in biomedicine for long-term implants.

W pracy przedstawiono badania woltamperometryczne procesu elektroosadzania cyrkonu z roztworu DMSO na różnych podłożach. Stwierdzono, że jest to procees wieloelektronowy zachodzący w kilku etapach. Ponadto otrzymano warstwy cyrkonu na tytanie, miedzi, stali kwasoodpornej i niklu. Wytworzony osad katodowy miał formę białego proszku, na skutek natychmiastowego utlenienia cyrkonu w kontakcie z powietrzem.

Scientists and medics are still searching for new metallic materials that can be used in medicine, e.g., as material for implants. The following article proposes materials based on titanium with vital elements prepared by combined powder metallurgy and arc melting methods. Four compositions of Ti-28Ta-9Nb, Ti-28Ta-19Nb, Ti-28Ta-9Zr and Ti-28Ta-19Zr (wt.%) have been prepared. The tested material was thoroughly analyzed by X-ray diffraction and scanning electron microscopy. Qualitative phase analysis using X-ray diffraction showed the presence of two phases, a' and ß titanium. In addition, a microhardness test was conducted, and the material was characterized in terms of corrosion properties. It was found that the corrosion resistance decreases with an increase of the ß phase presence. [ABSTRACT FROM AUTHOR]

This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives - niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-ß-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy. [ABSTRACT FROM AUTHOR]

Dental/osseous implants manufactured of titanium (Ti) have become a routine and affordable method in medical practice. To increase the overall safety and longtime stability of the implants further, the sophisticated approaches have been investigated in order to supply the implants with the bioactive surface layers. They have to serve two purposes: to increase the osseointegration capacity of the implants and to reduce the chances of bacterial growth and formation of bacterial biofilms leading to periimplantitis. Plasma electrolytic oxidation (PEO) is becoming a promising method to introduce functionalized surface layers on a metal substrate. Various PEO protocols have been suggested in order to achieve better biocompatibility of the dental implants and to increase their resistance to bacterial infections. It was also suggested that the PEO layers could increase resistance to corrosion on the surfaces of metallic implants. The dynamic processes running on the surface of Ti during the PEO processing still require efforts to fully understand the molecular mechanisms of the formation of hard and porous oxide surface layers. We and others have already shown that addition of a chelating agent to the bath electrolyte leads to better outcomes in the morphology and functional characteristics of the implants. Here we report in depth characterization of the PEO parameters and the produced PEO surface layers using the bath electrolyte containing another widely used chelating agent, nitrilotriacetic acid (NTA) along with potassium phosphate and calcium formate. The results will contribute to further understanding the mechanisms of the PEO process and to establishing routine protocols for commercial exploitation of the PEO method. [ABSTRACT FROM AUTHOR]

The paper presents the results on biofilm formation induced by pure Desulfovibrio desulfuricans strains and its effect on corrosion behaviour of 2205 duplex stainless steel (DSS). Biofilm formation and damage process stimulated by D. desulfuricans strains are analysed with reference to their metabolic activity and to the surface characterisation of structure and configuration of the biofilm. Electrochemical techniques are applied to monitor bacterial attachment to the steel surface and to determine the influence of bacteria on the passivity and corrosion resistance of 2205 DSS. The obtained results prove that 2205 DSS is rapidly colonised by D. desulfuricans and that the biofilms formed affect its corrosion resistance. Bacterial activity leads to the more noble corrosion potential values and to the increased current densities on the potentiodynamic polarisation curves. SEM observations reveal micropits as well as signs of crevice attack on the steel surface. [ABSTRACT FROM AUTHOR]

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The dynamically developing field of implantology requires researchers to search for new materials and solutions. In this study, TiNbZr samples were investigated as an alternative for popular, but potentially hazardous TiAl6V4. Samples were etched, sandblasted, subjected to PEO, and covered in AgNP suspension. Simultaneously, SEM images were taken, and the wettability and roughness of the surface were measured. Samples covered in AgNPs were subjected to biological trials. A six-day measurement of human fibroblast proliferation was conducted to assess biocompatibility, and the population of E. coli and S. aureus was measured over eight hours. Results showed that the TiNbZr PEO surface is biocompatible with human fibroblast cells and promotes growth. However, deposited AgNPs exhibited only slight effectiveness in decreasing bacterial growth over the first two hours. The results suggest that the method of surface preparation is sufficient and might promote osseointegration. On the other hand, more efficient and reliable methods of application of AgNPs should be researched.

This article presents a study on the functional properties and morphology of coatings based on amorphous silicon oxycarbide modified with phosphate ions and comodified with aluminum and boron. The objective of this modification was to enhance the biocompatibility and bioactivity without affecting its protective properties. The comodification was aimed toward stabilization of phosphate in the structure. The coatings were prepared according to the typical procedure for polymer-derived ceramics: synthesized via the sol-gel method, deposited using the dip-coating technique, and subsequently pyrolyzed. Comprehensive analyses of the morphology, surface properties, corrosion resistance, and bioactivity were conducted to assess their functional performance. The coatings exhibited uniform and smooth surfaces, with phase separation observed in the boron-modified Si BP OC series. Surface wettability and free energy measurements demonstrated that Si P OC and Si BP OC coatings possessed moderate hydrophilicity and favorable surface free energy for cell adhesion and bone tissue mineralization. Corrosion resistance tests in Ringer's solution revealed that Si BP OC coatings provided the highest protection against ion leaching, while Si AlP OC showed decreased resistance due to surface cracks. Bioactivity tests indicated calcium phosphate precipitation on the surface of all samples with higher hydroxyapatite formation on Si P OC and Si AlP OC coatings. In vitro tests using MG-63 osteoblast-like cells confirmed the biocompatibility of the coatings, with Si P OC and Si BP OC exhibiting the best combination of bioactivity, cell adhesion, and proliferation. These findings suggest that the phosphate- and boron-modified SiOC-based coatings are promising candidates for enhancing bone integration in orthopedic implants.

This study evaluated the bone-to-implant contact (BIC) of various surface-treated dental implants using high-resolution micro-CT in rabbit bone, focusing on the effects of different treatments on osseointegration and implant stability before and after bone demineralization. Six male New Zealand White rabbits were used. Four implant types were tested: machined surface with anodizing, only etching, sandblasting with Al 2 O 3 + etching, and sandblasting with TiO 2 + etching. Implants were scanned with high-resolution micro-CT before and after demineralization. Parameters like implant volume, surface area, and BIC were determined using specific software tools. During demineralization, the BIC changed about 6% for machined surface with anodizing, 5% for only etching, 4% for sandblasting with Al 2 O 3 + etching, and 10% for sandblasting with TiO 2 + etching. Demineralization reduced BIC percentages, notably in the machined surface with anodizing and sandblasting with TiO 2 + etching groups. Etching and sandblasting combined with etching showed higher initial BIC compared to anodizing alone. Demineralization negatively impacted the BIC across all treatments. This study underscores the importance of surface modification in implant integration, especially in compromised bone. Further research with larger sample sizes and advanced techniques is recommended.

This paper presents the surface treatment results of titanium, veterinary bone wedges. The functional coating is composed of a porous oxide layer (formed by a plasma electrolytic oxidation process) and a polymer poly(sebacic anhydride) (PSBA) layer loaded with amoxicillin (formed by dip coatings). The coatings were porous and composed of Ca (4.16%-6.54%) and P (7.64%-9.89% determined by scanning electron microscopy with EDX) in the upper part of the implant. The titanium bone wedges were hydrophilic (54° water contact angle) and rough (surface area (Sa):1.16 μm) The surface tension determined using diiodomethane was 68.6 ± 2.0° for the anodized implant and was similar for hybrid coatings: 60.7 ± 2.2°. 12.87 ± 0.91 µg/mL of amoxicillin was released from the implants during the first 30 min after immersion in the phosphate-buffered saline (PBS) solution. This concentration was enough to inhibit the Staphylococcus aureus ATCC 25923, and Staphylococcus epidermidis ATCC12228 growth. The obtained inhibition zones were between 27.3 ± 2.1 mm-30.7 ± 0.6 mm when implant extract after 1 h or 4 h immersion in PBS was collected. Various implant biocompatibility analyses were performed under in vivo conditions, including pyrogen test (3 rabbits), intracutaneous reactivity (3 rabbits, 5 places by side), acute systemic toxicity (20 house mice), and local lymph node assay (LLNA) (20 house mice). The extracts from implants were collected in polar and non-polar solutions, and the tests were conducted according to ISO 10993 standards. The results from the in vivo tests showed, that the implant's extracts are not toxic (mass body change below 5%), not sensitizing (SI < 1.6), and do not show the pyrogen effect (changes in the temperature 0.15ºC). The biocompatibility tests were performed in a certificated laboratory with a good laboratory practice certificate after all the necessary permissions., (© 2024. The Author(s).)

Titanium currently has a well-established position as the gold standard for manufacturing dental implants; however, it is not free of flaws. Mentions of possible soft-tissue discoloration, corrosion, and possible allergic reactions have led to the development of zirconia dental implants. Various techniques for the surface modification of titanium have been applied to increase titanium implants' ability to osseointegrate. Similarly, to achieve the best possible results, zirconia dental implants have also had their surface modified to promote proper healing and satisfactory long-term results. Despite zirconium oxide being a ceramic material, not simply a metal, there have been mentions of it being susceptible to corrosion too. In this article, we aim to review the literature available on zirconia implants, the available techniques for the surface modification of zirconia, and the effects of these techniques on zirconia's biological properties. Zirconia's biocompatibility and ability to osseointegrate appears unquestionably good. Despite some of its mechanical properties being, factually, inferior to those of titanium, the benefits seem to outweigh the drawbacks. Zirconia implants show very good success rates in clinical research. This is partially due to available methods of surface treatment, including nanotopography alterations, which allow for improved wettability, bone-to-implant contact, and osteointegration in general.

Photothermal therapy (PTT) is a method for eradicating tumor tissues through the use of photothermal materials and photosensitizing agents that absorb light energy from laser sources and convert it into heat, which selectively targets and destroys cancer cells while sparing healthy tissue. MXenes have been intensively investigated as photosensitizing agents for PTT. However, achieving the selectivity of MXenes to the tumor cells remains a challenge. Specific antibodies (Ab) against tumor antigens can achieve homing of the photosensitizing agents toward tumor cells, but their immobilization on MXene received little attention. Here, we offer a strategy for the selective ablation of melanoma cells using MXene-polydopamine-antiCEACAM1 Ab complexes. We coated Ti 3 C 2 T x MXene with polydopamine (PDA), a natural compound that attaches Ab to the MXene surface, followed by conjugation with an anti-CEACAM1 Ab. Our experiments confirm the biocompatibility of the Ti 3 C 2 T x -PDA and Ti 3 C 2 T x -PDA-antiCEACAM1 Ab complexes across various cell types. We also established a protocol for the selective ablation of CEACAM1-positive melanoma cells using near-infrared irradiation. The obtained complexes exhibit high selectivity and efficiency in targeting and eliminating CEACAM1-positive melanoma cells while sparing CEACAM1-negative cells. These results demonstrate the potential of MXene-PDA-Ab complexes for cancer therapy. They underline the critical role of targeted therapies in oncology, offering a promising avenue for the precise and safe treatment of melanoma and possibly other cancers characterized by specific biomarkers. Future research will aim to refine these complexes for clinical use, paving the way for new strategies for cancer treatment.

The newest technology allows the medical industry to manufacture innovative products such as milled titanium prosthodontic parts in an implant for a screw-retained suprastructure. In the literature, there are some articles on the clinical usage of subperiosteal implants, but none of these publications, either in PubMed or Google Scholar, thoroughly describe the workflow for the design and manufacture of individual implants for maxillofacial surgery with milled threads for a screw-retained prosthodontic bridge. The aim of the article is to present a step-by-step method of producing personalized implants, from the first steps of production to the implantation of the final product. The article includes information on patient qualification for surgery, computational preparation and skull printing, planning of Mai Implants ® , meshing, 3D printing and milling, cleaning, rinsing, anodizing, and laser marking, as well as the cleaning and sterilization process in a hospital or dental clinic. A detailed description of implant production allows for the analysis of each step and the development of technology. The production of implants is an expensive procedure, but considering all the advantages of the Mai Implants ® treatment and the disadvantages of alternatives, the product is worth the price.

This paper reports the results of our study on electrochemical polishing of titanium and a Ti-based alloy using non-aqueous electrolyte. It was shown that electropolishing ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The research was conducted using samples made of titanium and Ti 6 Al 4 V alloy, as well as implant system elements: implant analog, multiunit, and healing screw. Electropolishing was carried out under a constant voltage (10-15 V) with a specified current density. The electrolyte used contained methanol and sulfuric acid. The modified surface was subjected to a thorough analysis regarding its surface morphology, chemical composition, and physicochemical properties. Scanning electron microscope images and profilometer tests of roughness confirmed significantly smoother surfaces after electropolishing. The surface profile analysis of processed samples also yielded satisfactory results, showing less imperfections than before modification. The EDX spectra showed that electropolishing does not have significant influence on the chemical composition of the samples.

This research aimed to evaluate the effectiveness of new organic substances, including a novel ionic liquid based on polyhexamethylenebiguanidine, polyhexamethyleneguanidine, and safranin in the copper electrorefining process. Experiments were conducted on a small laboratory scale using industrial copper anodes. Single doses of new additives did not improve process indicators (current efficiency, average cell voltage, specific energy consumption) or the quality of copper cathode deposits. However, a combination of a new ionic liquid based on polyhexamethylenebiguanidine and thiourea resulted in a satisfactory current efficiency of 97%, an average cell voltage of 0.110 V, a low specific energy consumption index of approximately 100 kWh/t Cu , and smooth cathode surfaces. These results were superior to those obtained with industrial additives (bone glue and thiourea). The findings enhance our understanding of how these substances influence the electrorefining process and suggest the potential for more efficient and sustainable methods. Further research is recommended to validate these findings and explore their industrial applications.

The study involved numerical FEA (finite element analysis) of dental implants. Based on this, fatigue tests were conducted according to the PN-EN 14801 standard required for the certification of dental products. Thanks to the research methodology developed by the authors, it was possible to conduct a thorough analysis of the impact of external and internal factors such as material, geometry, loading, and assembly of the dental system on the achieved value of fatigue strength limit in the examined object. For this purpose, FEM studies were based on identifying potential sites of fatigue crack initiation in reference to the results of the test conducted on a real model. The actions described in the study helped in the final evaluation of the dental system design process named by the manufacturer as INTEGRA OPTIMA 3.35. The objective of the research was to identify potential sites for fatigue crack initiation in a selected dental system built on the INTEGRA OPTIMA 3.35 set. The material used in the research was titanium grade 4. A map of reduced von Mises stresses was used to search for potential fatigue crack areas. The research [loading] was conducted on two mutually perpendicular planes positioned in such a way that the edge intersecting the planes coincided with the axis of the system. The research indicated that the connecting screw showed the least sensitivity (stress change) to the change in the loading plane, while the value of preload has a significant impact on the achieved fatigue strength of the system. In contrast, the endosteal implant (root) and the prosthetic connector showed the greatest sensitivity to the change in the loading plane. The method of mounting [securing] the endosteal implant using a holder, despite meeting the standards, may contribute to generating excessive stress concentration in the threaded part. Observation of the prosthetic connector in the Optima 3.35 system, cyclically loaded with a force of F ≈ 300 N in the area of the upper hexagonal peg, revealed a fatigue fracture. The observed change in stress peak in the dental connector for two different force application surfaces shows that the positioning of the dental system (setting of the socket in relation to the force action plane) is significantly decisive in estimating the limited fatigue strength.

The paper presents the results of preliminary research on the possibility of synthesizing ZnO-TiO 2 mixed coatings by plasma electrochemical oxidation (PEO). The aim of the work was to synthesize TiO 2 -ZnO mixed coatings on a titanium substrate from an electrolyte containing ZnO nanoparticles (NPs) and to assess the parameters of PEO on the structure, chemical composition, and properties of the obtained oxide coatings. The PEO process was carried out under various current-voltage conditions using different signals: DC, DC pulse, and AC. In this work, optimal conditions for the PEO process were determined to obtain well-adhering oxide coatings with the highest possible content of ZnO. The structure and morphology of the resulting oxide coatings were investigated, and their chemical and phase composition was comprehensively examined (EDX, XRD, XPS, and GD-OES). In addition, their basic optical properties were assessed. It has been shown that in the PEO DC pulse process, it is possible to obtain oxide coatings characterized by a high degree of structure order, high ZnO content in the oxide coating (3.6 at.%, XPS), and prospective applications for photocatalytic purposes (3.12 eV).

The increased demand for implants that do not pose a threat to patients diagnosed using high-resolution magnetic resonance imaging and concerns arising from titanium allergies require the development of alternative implant materials. One promising concept is a use of zirconium as corrosion-resistant, nontoxic material that is lower in magnetic susceptibility. To achieve this, safe and efficient surface treatment methods of zirconium metal have to be developed. In this study, zirconium samples were treated with fluoride-free and fluoride-containing etching mixtures to determine their effect on the surface of Zr. SEM images were taken to investigate the preliminary effects of the etchants. Then, a second set of experiments was carried out using mixtures of HF-H 2 SO 4 and ammonium persulfate-fluoride salts, as they gave the most promising results in the first trial. SEM images were taken and measurements on roughness, wettability, and atomic composition were made. The results showed an even zirconium surface in APS-fluoride salts, along with the formation of pits (1-3 μm) similar to those found in commercially available implants. There was no significant increase in the roughness of the treated samples. The addition of NO 3 - ions in the form of KNO 3 speeded up etching and promoted pit formation. The HF-H 2 SO 4 mixture was found to give unsatisfying results, as the surface was too rough and the formed pits were too large. It was concluded that etching zirconium in ammonium persulfate and fluoride salts is a promising area of research for the preparation of zirconium implants; however, further research has to be carried out on sandblasted samples.

Background: Presently, the management of patients with maxilla bone defects of the Cawood V or VI class is achieved using zygomatic or individual implants or through augmentation of the bone. For zygomatic implants, the ORIS criteria represent the most common factor in helping practitioners register success rates. The zygomatic anatomy-guided approach (ZAGA)and zygomatic orbital floor (ZOF) are factors that are crucial to examining the anatomy of a particular patient before the procedure. The aim of thisarticle is to find the statistical relationship between the abovementioned terms and other factors., Methods: A total of 81 patients underwent zygomatic implant procedures in different configurations. The ORIS, ZAGA, and ZOF parameters were compared with other factors such as type of surgery, sex, age, and the anatomy of the zygomatic bone., Results: Most patients in this article were classified as ZAGA Class 2. The relationships between type of surgery and ZAGA classification, and ZAGA and sinus/maxilla zygomatic implant localization were statistically significant., Conclusions: The ZAGA and ZOF scales are practical and valuable factors that should be taken into account before surgery, whereas to date, criteria better than the ORIS scale have not been described in terms of the success of zygomatic implants. The ZOF scale might omit perforation of the orbit because this parameter warns a practitioner to be aware of the anatomy of the orbit.