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Bio-Implants Derived from Biocompatible and Biodegradable Biopolymeric Materials
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
The implant material shows the proper response in a biological environment is referred as biocompatible. It also referred as the corrosion resistance and cytotoxicity of the products. Corrosion resistance [67–69] basically means the release of metallic ions from metal surface to the surrounding environment. There are many types of corrosion crevice corrosion, pitting corrosion, galvanic corrosion, electrochemical corrosion, etc. Clinical significance of corrosion is that the implant made up of bio-material should have the corrosion resistance. Corrosion can results into rough surface, weak restoration, release of elements from the metal or alloy, toxic reactions, etc. There can be allergic reactions in patients due to corrosion.
Introduction to Bio-Implants
Published in S Santhosh Kumar, Somashekhar S. Hiremath, Role of Surface Modification on Bacterial Adhesion of Bio-Implant Materials, 2020
S Santhosh Kumar, Somashekhar S. Hiremath
The materials used in the implants should be a biocompatible, corrosion resistance, and wear resistance; they should have excellent mechanical properties and better Osseo-integration; and should not create any effect on biological system/tissue (Mahajan and Sindhu, 2018). All the available materials on earth cannot be used as biomaterials. Researchers have developed plenty of materials that can be used as biomaterials and are continually working towards developing new biocompatible materials. Some of the factors affecting implant biomaterial are chemical factors: these include three basic types of corrosion: general, pitting, and crevice; surface specific factors: the events at the bone-implant interface can be divided into the behaviour of the implant material, the host response; electrical factors: physiochemical methods, morphologic methods, and biochemical methods; mechanical factor: modulus of elasticity, tensile or compressive forces, and elongation and metallurgical aspects. The biomaterials are classified under metals, ceramics, and polymers. Some of the major materials used in the implants are listed as follows:
Orally Induced Tolerance to Nickel: The Role of Oral Exposure (Orthodontic Devices) in Preventing Sensitization
Published in Jurij J. Hostýnek, Howard I. Maibach, Nickel and the Skin, 2019
Jurij J. Hostýnek, Katherine E. Reagan, Howard I. Maibach
Release of metal ions from the four commercial nickel-chrome dental-casting alloys was further investigated by Bumgardner and Lucas (1995) in incremental three-dimensional cell-culture tests. Metal ion release was correlated to changes in cellular morphology, viability, and proliferation. Morphology or viability were not affected by the alloys’ corrosion products, but cellular proliferation did decrease. Analysis of nickel levels showed that of the alloys tested, Neptune released the statistically lowest amount of nickel, and also caused the smallest decrease in cellular proliferation. Pure nickel samples released greater than 324 ppm nickel over the 24 to 72 h tests. These levels are 1000 times greater than those determined from the commercial alloys. All alloys released statistically increasing amounts of nickel ions at successive test intervals. Based on this and the previous studies (Bumgardner and Lucas, 1993; Bumgardner and Lucas, 1994) the authors express concern over corrosion resistance and the biocompatibility of certain dental alloys, due to a perceived potential for accelerated corrosion and the exposure of local and systemic tissues to elevated levels of corrosion products. They conclude, however, that nickel-based dental-casting alloys containing sufficient chromium (16 to 27%) to create a homogenous surface oxide layer are most desirable for corrosion stability of dental appliances.
Exploring the functionalization of Ti-6Al-4V alloy with the novel antimicrobial peptide JIChis-2 via plasma polymerization
Published in Biofouling, 2023
Gabriella Teresinha Lima Teixeira, Rogério Valentim Gelamo, Malu Mateus Santos Obata, Leonardo Eurípedes de Andrade Silva, Marcos Vinícius da Silva, Carlo José Freire de Oliveira, Brunela Pereira da Silva, Idalina Vieira Aoki, Jeferson Aparecido Moreto, Natália Bueno Leite Slade
Considering that the release of metal ions can cause adverse effects on the organism (Prando et al. 2017), it is worth mentioning that the biocompatibility of biomedical devices is related to the corrosion resistance of these materials. Titanium-based materials have excellent corrosion resistance properties, which occur due to the spontaneous formation of a thin layer of titanium dioxide (2011; Maestro et al. 2021). This layer has a protective character and gives the material excellent biological properties (Lyon 2012; Panayotov et al. 2015). Despite this, these materials are susceptible to uniform and localized corrosion in aggressive environments such as the physiological environment (Trino et al. 2018). To explore the corrosion properties of the surfaces used in this study, immersion tests were carried out in a corrosive medium of 0.1 mol L−1 NaF solution at different immersion times (1, 3, 10, 15 and 24 h). The choice of this solution is attributed to the effect of fluoride ions, which affect the stability of the passive oxide layer of titanium-based materials through the dissolution of Ti (Sivakumar et al. 2011; Prando et al. 2017). Thus, it was possible to analyze the stability of the samples in this medium, considering the differences between the base material and the surfaces coated with PAA and with the peptide at different immersion times.
Analytical review on the biocompatibility of surface-treated Ti-alloys for joint replacement applications
Published in Expert Review of Medical Devices, 2022
In [85], Bains et al. presented the surface modification on Ti–6Al–4 V alloy. The surface was treated with HA powder using Electro Discharge Coating (EDC). The experimental analysis was executed using input parameters such as pulse-off-time, pulse-on-time, and current. The result was evaluated on surface roughness, material deposition rate, and micro-hardness. The HA-EDC surface treatment makes the surface bioactive and creates a porous texture. In vitro and electrochemical analysis was performed to evaluate the surface properties of the modified surface. When the result was compared between treated and untreated surfaces, it was noticed that corrosion resistance was increased by 91.26%, and wear resistance was increased 87% as a juxtaposition to an untreated surface. It was also seen that Titanium alloy surface modifying methods enhance the material’s bioactivity [86–88].
Probing the correlation between corrosion resistance and biofouling of thermally sprayed metallic substrata in the field
Published in Biofouling, 2022
Pedro A. Vinagre, Johan B. Lindén, Enara Mardaras, Emiliano Pinori, Johan Svenson
Salt spray testing was further employed to correlate the electrochemical corrosion data and to evaluate the general quality of the thermal sprayed coating to verify if there were any process induced defects that could affect the corrosion protection. The salt spray test also evaluated how the previous results might relate to the field tests and to ensure the ranging corrosion resistance of the materials before field trials. The standardized salt spray test employed a continuous spray of a salt solution (5 wt% NaCl) with neutral pH around 6.5 (ASTM B117-11 2018). Coatings can react differently in such laboratory tests in comparison with field trials as different salt compositions are found in natural seawater, which also has a higher pH of around 8.1. Whilst the foreword of the international standard ISO 9227:2017 (ISO 9227:2017 2017), (which is equivalent to ASTM B117 (ASTM B117-11 2018)) standard for salt spray testing states this test is not recommended for comparison of different coatings or metals, the test is employed here to investigate if the materials were different in regard to corrosion resistance. The test is generally well suited for rapid analysis of discontinuities, pores, and damage in inorganic or organic coatings. Visual examination of the samples was performed after exposure for 24, 72, 192, 336, and 528 h, as shown in Figure 4.