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Implant corrosion

Yuxiang Wang, Di Tie, Renguo Guan, Ning Wang, Yingqiu Shang, Tong Cui, Junqiao Li
In previous studies, Mg-Sr alloys exhibited great biocompatibility with regard to test animals, and enhanced peri-implant bone formation. The objective of the present study was to investigate the effects of heat treatments on the mechanical and corrosion properties of Mg-Sr alloys. Various heat-treated Mg-xSr (x = 0.5, 1, and 2wt%, nominal composition) alloys were prepared using homogenization and aging treatments. Mechanical tests were performed at room temperature on the as-cast, homogenized, and peak-aged alloys...
August 24, 2017: Journal of the Mechanical Behavior of Biomedical Materials
Sae-Mi Kim, Min-Ho Kang, Hyoun-Ee Kim, Ho-Kyung Lim, Soo-Hwan Byun, Jong-Ho Lee, Sung-Mi Lee
The utility of a novel ceramic/polymer-composite coating with a micro-textured microstructure that would significantly enhance the functions of biodegradable Mg implants is demonstrated here. To accomplish this, bioactive hydroxyapatite (HA) micro-dots can be created by immersing a Mg implant with a micro-patterned photoresist surface in an aqueous solution containing calcium and phosphate ions. The HA micro-dots can then be surrounded by a flexible poly(l-lactic)-acid (PLLA) polymer using spin coating to form a HA/PLLA micro-textured coating layer...
December 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
M Sikora-Jasinska, C Paternoster, E Mostaed, R Tolouei, R Casati, M Vedani, D Mantovani
Recently, Fe and Fe-based alloys have shown their potential as degradable materials for biomedical applications. Nevertheless, the slow corrosion rate limits their performance in certain situations. The shift to iron matrix composites represents a possible approach, not only to improve the mechanical properties, but also to accelerate and tune the corrosion rate in a physiological environment. In this work, Fe-based composites reinforced by Mg2Si particles were proposed. The initial powders were prepared by different combinations of mixing and milling processes, and finally consolidated by hot rolling...
December 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Anna Di Laura, Paul D Quinn, Vasiliki C Panagiotopoulou, Harry S Hothi, Johann Henckel, Jonathan J Powell, Fitim Berisha, Fernanda Amary, J Fred W Mosselmans, John A Skinner, Alister J Hart
The mechanisms of metal release from the articulation at the head cup bearing and the tapered junctions of orthopaedic hip implants are known to differ and the debris generated varies in size, shape and volume. Significantly less metal is lost from the taper junction between Cobalt-Chromium-Molybdenum (CoCrMo) and Titanium (Ti) components (fretting-corrosion dominant mechanism), when compared to the CoCrMo bearing surfaces (wear-corrosion dominant mechanism). Corrosion particles from the taper junction can lead to Adverse Reactions to Metal Debris (ARMD) similar to those seen with CoCrMo bearings...
September 8, 2017: Scientific Reports
Tiantian Hui, Gregory W Kubacki, Jeremy L Gilbert
Fretting corrosion (or mechanically assisted corrosion, MAC) is a major corrosion mechanism in modular orthopedic implants. There is a complex interplay between fretting corrosion and the surrounding biological environment that includes particle generation and electrochemical potential excursions and currents. The goal of this work is to directly investigate the effects of fretting on cells in vitro. Using an in vitro fretting device, MC3T3 preosteoblasts were cultured onto Ti-6Al-4V disks adjacent to the fretting site...
September 7, 2017: Journal of Biomedical Materials Research. Part A
Robin Pourzal, Deborah J Hall, Jonas Ehrich, Stephanie M McCarthy, Mathew T Mathew, Joshua J Jacobs, Robert M Urban
BACKGROUND: Adverse local tissue reactions (ALTRs) triggered by corrosion products from modular taper junctions are a known cause of premature THA failure. CoCrMo devices are of particular concern because cobalt ions and chromium-orthophosphates were shown to be linked to ALTRs, even in metal-on-polyethylene THAs. The most common categories of CoCrMo alloy are cast and wrought alloy, which exhibit fundamental microstructural differences in terms of grain size and hard phases. The impact of implant alloy microstructure on the occurring modes of corrosion and subsequent metal ion release is not well understood...
September 7, 2017: Clinical Orthopaedics and related Research
Ehsan Bonyadi Rad, Sepideh Mostofi, Matthias Katschnig, Patrik Schmutz, Magdalena Pawelkiewicz, Regine Willumeit-Römer, Ute Schäfer, Annelie Weinberg
The biodegradable magnesium-based implants have been widely utilized in medical orthopedic applications in recent years. We have recently shown that direct culture on Pure Mg and Mg2Ag alloys lead to a progressive differentiation impairment of MC3T3-E1 pre-osteoblasts. In this study, we aimed to analyze the apoptotic reaction of MC3T3-E1 cells in response to the direct culture on Pure Mg, Mg2Ag and Extreme High Pure Mg (XHP Mg) alloy samples. Our results demonstrated that long-term culturing of MC3T3-E1 cells on Pure Mg and Mg2Ag alloys induce time-dependent expression of active caspase-3 (active casp-3) and cleaved PARP-1 (cl...
September 5, 2017: Journal of Materials Science. Materials in Medicine
Ewa Dobruchowska, Monika Paziewska, Krzysztof Przybyl, Kazimierz Reszka
PURPOSE: The endoprostheses made of cobalt-chromium-molybdenum (Co-Cr-Mo) alloys belong to the group of the most popular metallic implants used for reconstruction of hip joints. For such biomaterials, the primary goal is a correct and long-term functioning in the aggressive environment of body fluids. Therefore, the purpose of this study was to examine both the morphology and the corrosion resistance of implants made of the cobalt alloy used in Birmingham Hip Resurfacing (BHR) system (Smith & Nephew)...
2017: Acta of Bioengineering and Biomechanics
Ningning Bai, Cui Tan, Qing Li, Zhongxian Xi
In this paper, a low-cost and multifunctional hydroxyapatite (HA)/pefloxacin (PFLX) drug eluting layer is coated on magnesium (Mg) alloy through a simple hydrothermal and dip process. The drug PFLX could provide effective prevention for bone infection and inflammation due to its broad-spectrum antibacterial property. And HA would promote the growth of new bone and further improve the biocompatibility of implants. Besides, both PFLX and HA exhibits excellent corrosion protection for Mg alloy substrate. This coating is of great value for improving the application of Mg alloy as biomaterials...
2017: Bio-medical Materials and Engineering
Shervin Eslami Harandi, Parama Chakraborty Banerjee, Christopher D Easton, R K Singh Raman
It is essential for any temporary implant to possess adequate strength to maintain their mechanical integrity under the synergistic effects of mechanical loading characteristics of human body and the corrosive physiological environment. Such synergistic effects can cause stress corrosion cracking (SCC). The aim of the present study is to investigate the effect of the addition of bovine serum albumin (BSA) to Hanks' solution in corrosion and SCC susceptibility of AZ91D magnesium alloy. The electrochemical impedance spectroscopy (EIS) results indicated that the addition of BSA increased corrosion resistance of the alloy during the first 48h of immersion and then decreased it rapidly...
November 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Hongtao Yang, Cong Wang, Chaoqiang Liu, Houwen Chen, Yifan Wu, Jintao Han, Zichang Jia, Wenjiao Lin, Deyuan Zhang, Wenting Li, Wei Yuan, Hui Guo, Huafang Li, Guangxin Yang, Deling Kong, Donghui Zhu, Kazuki Takashima, Liqun Ruan, Jianfeng Nie, Xuan Li, Yufeng Zheng
In the present study, pure zinc stents were implanted into the abdominal aorta of rabbits for 12 months. Multiscale analysis including micro-CT, scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM) and histological stainings was performed to reveal the fundamental degradation mechanism of the pure zinc stent and its biocompatibility. The pure zinc stent was able to maintain mechanical integrity for 6 months and degraded 41.75 ± 29.72% of stent volume after 12 months implantation...
August 16, 2017: Biomaterials
Stacey J L Sullivan, Daniel Madamba, Shiril Sivan, Katie Miyashiro, Maureen L Dreher, Christine Trépanier, Srinidhi Nagaraja
A major limitation with current assessments of corrosion in metallic medical devices is the lack of correlation between in-vitro and in-vivo corrosion performance. Therefore, the objective of this study was to elucidate the relationship between pitting corrosion measured by breakdown potentials (Eb) in ASTM F2129 testing and corrosion resistance in-vivo. Four groups of Nitinol stents were manufactured using different processing methods to create unique surface properties. The stents were implanted into iliac arteries of minipigs for six months and explanted for corrosion analysis...
August 24, 2017: Acta Biomaterialia
Aaron F Cipriano, Jiajia Lin, Christopher Miller, Alan Lin, Mayra C Cortez Alcaraz, Pedro Soria, Huinan Liu
This article reports anodization of Mg in KOH electrolyte and the associated surface, degradation, and biological properties for bioresorbable implant applications. The preparation procedures for electrodes and anodization setup significantly enhanced reproducibility of samples. The results of anodization performed at the applied potentials of 1.8, 1.9, or 2.0 V showed that the sample anodized at 1.9 V and annealed, referred to as the 1.9 AA sample, had homogenous surface microstructure and elemental composition, and a reduction in corrosion current density in the electrochemical testing...
August 14, 2017: Acta Biomaterialia
S M Perren, P Regazzoni, A A Fernandez
BIOLOGICAL ASPECTS OF STEEL AND TITANIUM AS IMPLANT MATERIAL IN ORTHOPEDIC TRAUMA SURGERY The following case from the ICUC database, where a titanium plate was implanted into a flourishing infection, represents the clinical experience leading to preferring titanium over steel. (Fig. 1) (6). Current opinions regarding biological aspects of implant function. The "street" opinions regarding the biological aspects of the use of steel versus titanium as a surgical trauma implant material differ widely. Statements of opinion leaders range from "I do not see any difference in the biological behavior between steel and titanium in clinical application" to "I successfully use titanium implants in infected areas in a situation where steel would act as foreign body "sustaining" infection...
2017: Acta Chirurgiae Orthopaedicae et Traumatologiae Cechoslovaca
N Espallargas, A Fischer, A Igual Muñoz, S Mischler, M A Wimmer
Artificial hip joints operate in aqueous biofluids that are highly reactive towards metallic surfaces. The reactivity at the metal interface is enhanced by mechanical interaction due to friction, which can change the near-surface structure of the metal and surface chemistry. There are now several reports in the literature about the in-situ generation of reaction films and tribo-metallurgical transformations on metal-on-metal hip joints. This paper summarizes current knowledge and provides a mechanistic interpretation of the surface chemical and metallurgical phenomena...
June 2017: Biotribology (Oxf)
Ghada O Alrabeah, Peter Brett, Jonathan C Knowles, Haralampos Petridis
OBJECTIVES: The etiology of the reduced marginal bone loss observed around platform-switched implant-abutment connections is not clear but could be related to the release of variable amounts of corrosion products. The present study evaluated the effect of different concentrations of metal ions released from different implant abutment couples on osteoblastic cell viability, apoptosis and expression of genes related to bone resorption. METHODS: Osteoblastic cells were exposed to five conditions of culture media prepared containing metal ions (titanium, aluminum, vanadium, cobalt, chromium and molybdenum) in different concentrations representing the amounts released from platform-matched and platform-switched implant-abutment couples as a result of an earlier accelerated corrosion experiment...
August 4, 2017: Journal of Dentistry
(no author information available yet)
As this study implicates a role for corrosion in peri-implantitis, there may be a clear distinction between the aetiology of peri-implantitis and periodontitis.
August 11, 2017: British Dental Journal
A M Oje, A A Ogwu
Chromium oxide coatings prepared by radiofrequency reactive magnetron sputtering on stainless steel substrates were exposed to Ringer's physiological solution and tested for their electrochemical corrosion stability using an open circuit potential measurement, potentiodynamic polarization, electrochemical impedance spectroscopy and Mott-Schottky analysis. The coatings were found to be predominantly Cr2O3, based on the observation of the dominance of [Formula: see text] and Eg symmetric modes in our Raman spectroscopic investigation and the Eu vibrational modes in our Fourier transform infrared spectroscopic measurements on the coatings...
July 2017: Royal Society Open Science
Supriya Kheur, Nimisha Singh, Dhananjay Bodas, Jean-Yves Rauch, Shantanu Jambhekar, Mohit Kheur, Jyutika Rajwade
Although titanium dental implants are biocompatible, exhibit excellent corrosion resistance and high mechanical resistance, the material fails in providing resistance to infection because it exhibits poor antimicrobial activity. To address these issues, we deposited silver onto titanium abutments (Grade 5 titanium discs) using direct current (DC) sputtering and assessed the antimicrobial activity and biocompatibility of the modified implant material. Atomic absorption spectrometry and X-ray photoelectron spectroscopy were employed to investigate the concentration and elemental composition of the deposited silver...
July 29, 2017: Colloids and Surfaces. B, Biointerfaces
Marta M Alves, Ons Bouchami, Ana Tavares, Laura Córdoba, Catarina F Santos, Maria Miragaia, Maria de Fátima Montemor
ZnO nanoparticles (NPs) are arising as promising novel antibiotics toward device-related infections. The surface functionalization of Zn, a novel resorbable biomaterial, with ZnO NPs could present an effective solution to overcome such a threat. In this sense, the antibacterial and antibiofilm activity of nano- and microsized ZnO coatings was studied against clinically relevant bacteria, methicillin resistant Staphylococcus aureus (MRSA). The bacterial viability of planktonic and biofilm cells together with the corresponding biofilm structures revealed that only the nanosized ZnO coating had an antibiofilm effect...
August 30, 2017: ACS Applied Materials & Interfaces
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