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Implant corrosion

Sina Naddaf Dezfuli, Zhiguang Huan, Arjan Mol, Sander Leeflang, Jiang Chang, Jie Zhou
The present research was aimed at developing magnesium-matrix composites that could allow effective control over their physiochemical and mechanical responses when in contact with physiological solutions. A biodegradable, bioactive ceramic - bredigite was chosen as the reinforcing phase in the composites, based on the hypothesis that the silicon- and magnesium-containing ceramic could protect magnesium from fast corrosion and at the same time stimulate cell proliferation. Methods to prepare composites with integrated microstructures - a prerequisite to achieve controlled biodegradation were developed...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Jaroslav Čapek, Šárka Msallamová, Eva Jablonská, Jan Lipov, Dalibor Vojtěch
Recently, iron-based materials have been considered as candidates for the fabrication of biodegradable load-bearing implants. Alloying with palladium has been found to be a suitable approach to enhance the insufficient corrosion rate of iron-based alloys. In this work, we have extensively compared the microstructure, the mechanical and corrosion properties, and the cytotoxicity of an FePd2 (wt%) alloy prepared by three different routes - casting, mechanical alloying and spark plasma sintering (SPS), and mechanical alloying and the space holder technique (SHT)...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Reza H Oskouei, Mohammad Reza Barati, Hamidreza Farhoudi, Mark Taylor, Lucian Bogdan Solomon
A detailed investigation was performed to characterize the fretting wear and corrosion damage to the neck component of a CoCrMo stem from a metal-on-polyethylene implant retrieved after 99months. The stem was a low-carbon (0.07wt%) wrought Co-28Cr-6Mo alloy with no secondary carbide phases in the matrix (γ-phase). The original design of the neck surface contained an intentionally fabricated knurled profile with a valley-to-peak range of approximately 11μm. Roughness measurements indicated that the tip of the knurled profile was significantly damaged, especially in the distal medial region of the neck, with up to a 22% reduction in the mean peak-to-valley height (Ra) compared to the original profile...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Hanning Li, Yanan Wang, Qiuming Peng
A new strategy of accumulative cryo-rolling (ACR) at liquid nitrogen temperature and annealing was performed to improve degradation rate of Fe-Mn-based implants. Differing from as-cast and ACRed Fe-Mn-based alloys with single-phase austenite, ACRed-annealed sample mainly consists of austenite and non-equilibrium Fe5C2 precipitate. ACR-annealed sample shows a degradation rate of 0.0388mA·cm(-2), which is 4.6 times higher than as-cast alloy. Pitting corrosion plays a dominant role in both as-cast and ACRed samples...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Shoujie Liu, Hejun Li, Leilei Zhang, Xuemin Yin, Yao Guo
Surface modification is to modify biological responses through changing surface properties without reducing the mechanical properties of the implant. Specifically bioactive coatings, such as hydroxyapatite, carbonate apatite and dicalcium phosphate dehydrate, have been deposited on carbon/carbon (C/C) composites to change the bio-inert surface state. This work focused on the effects of voltages and electrolyte concentrations of pulsed electrodeposition on apatite layer. The apatite coatings thus synthesized were then structurally, morphologically and chemically characterized using X-ray diffraction, scanning electron microscopy, Transmission electron microscopy and Fourier-transform infrared spectroscopy...
October 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Annika Krull, Michael M Morlock, Nicholas E Bishop
BACKGROUND: Intraoperative interface contamination of modular head-stem taper junctions of hip implants can lead to poor fixation strength, causing fretting and crevice corrosion or even stem taper fracture. Careful cleaning before assembly should help to reduce these problems. The purpose of this study was to determine the effect of cleaning (with and without drying) contaminated taper interfaces on the taper fixation strength. METHODS: Metal or ceramic heads were impacted onto titanium alloy stem tapers with cleaned or contaminated (fat or saline solution) interfaces...
May 13, 2017: Journal of Arthroplasty
Beth Sherman, Tanya Crowell
PURPOSE: Metal implants have been used to treat adolescent idiopathic scoliosis since the 1960s. Only recently, however, it has the issue of metal-bone breakdown secondary to metal corrosion in situ come to light, raising concerns of possible long-term complications from the resulting metallosis and inflammation of spinal tissues. We present a case of a patient with neurological deficit, pain, and disability with Harrington rod in place for over 30 years, to bring attention to the issue of bio-corrosion of metal implants and its effect on human tissue...
June 17, 2017: European Spine Journal
K Apaza-Bedoya, M Tarce, C A M Benfatti, B Henriques, M T Mathew, W Teughels, J C M Souza
Two-piece implant systems are mainly used in oral implantology involving an osseointegrated implant connected to an abutment, which supports prosthetic structures. It is well documented that the presence of microgaps, biofilms and oral fluids at the implant-abutment connection can cause mechanical and biological complications. The aim of this review paper was to report the degradation at the implant-abutment connection by wear and corrosion processes taking place in the oral cavity. Most of the retrieved studies evaluated the wear and corrosion (tribocorrosion) of titanium-based materials used for implants and abutments in artificial saliva...
June 14, 2017: Journal of Periodontal Research
J I Silva, A C Alves, A M Pinto, F Toptan
Ti and its alloys are attractive materials for variety of fields, including biomedical implants, however, the wear behavior is yet to be improved. In the present work, Ti-TiB-TiNx in-situ metal matrix composites were synthesized by reactive hot pressing using a Ti-BN powder blend. Corrosion behavior was investigated in 9g/L NaCl solution at 37°C by performing potentiodynamic polarization and electrochemical impedance spectroscopy. Tribocorrosion behavior was investigated using reciprocating tribometer, against an alumina ball, under 1 and 10N normal load, 1 and 2Hz frequency, in 9g/L NaCl solution at 37°C...
June 8, 2017: Journal of the Mechanical Behavior of Biomedical Materials
Yanan Jiang, Bi Wang, Zhanrong Jia, Xiong Lu, Liming Fang, Kefeng Wang, Fuzeng Ren
Magnesium alloys have the great potential to be used as orthopaedic implants due to their biodegradability and mechanical resemblance to human cortical bone. However, the rapid degradation in physiological environment with the evolution of hydrogen gas release hinders their clinical applications. In this study, we developed a novel functional and biocompatible coating strategy through polydopamine mediated assembly of hydroxyapatite nanoparticles and growth factor, bone morphogenetic protein-2 (BMP-2), onto the surface of AZ31 Mg alloys...
June 12, 2017: Journal of Biomedical Materials Research. Part A
Robert K Shepherd, Andrew K Wise, Ya Lang Enke, Paul M Carter, James B Fallon
OBJECTIVE: Cochlear implants (CIs) have a limited number of independent stimulation channels due to the highly conductive nature of the fluid-filled cochlea. Attempts to develop highly focused stimulation to improve speech perception in CI users includes the use of simultaneous stimulation via multiple current sources. Focused multipolar (FMP) stimulation is an example of this approach and has been shown to reduce interaction between stimulating channels. However, compared with conventional biphasic current pulses generated from a single current source, FMP is a complex stimulus that includes extended periods of stimulation before charge recovery is achieved, raising questions on whether chronic stimulation with this strategy is safe...
June 13, 2017: Journal of Neural Engineering
Yufu Ren, Elham Babaie, Boren Lin, Sarit Bhaduri
Due to the combination of many unique properties, magnesium alloys have been widely recognized as the suitable metallic material for degradable biomedical implants. However, extremely high degradation kinetics of magnesium alloys in physiological environment have hindered their clinical applications. This paper reports for the first time of using a novel microwave assisted coating process to deposit magnesium phosphate coatings on Mg alloy AZ31 and improve its the in vitro corrosion resistance. Results present that newberyite layer and trimagnesium phosphate hydrate (TMP) layer with distinct features were fabricated via various processing time and temperature...
June 12, 2017: Biomedical Materials
Thom Bitter, Imran Khan, Tim Marriott, Elaine Lovelady, Nico Verdonschot, Dennis Janssen
Fretting corrosion at the taper interface of modular hip implants has been implicated as a possible cause of implant failure. This study was set up to gain more insight in the taper mechanics that lead to fretting corrosion. The objectives of this study therefore were (1) to select experimental loading conditions to reproduce clinically relevant fretting corrosion features observed in retrieved components, (2) to develop a finite element model consistent with the fretting experiments and (3) to apply more complicated loading conditions of activities of daily living to the finite element model to study the taper mechanics...
June 1, 2017: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
Ben M Vierra, Sarah R Blumenthal, Derek F Amanatullah
Modular implants are currently widely used in total hip arthroplasty because they give surgeons versatility during the operation, allow for easier revision surgery, and can be adjusted to better fit the anatomy of the specific patient. However, modular implants, specifically those that have metal-on-metal junctions, are susceptible to crevice and fretting corrosion. This can ultimately cause implant failure, inflammation, and adverse local tissue reaction, among other possible side effects. Surgeons should be aware of the possibility of implant corrosion and should follow a set of recommended guidelines to systematically diagnose and treat patients with corroded implants...
June 9, 2017: Orthopedics
Hui Cheng, Yanling Zhang, Bei Zhang, Jie Cheng, Weiqi Wang, Xin Tang, Peng Teng, Yanyu Li
In this study, we investigated the rejection of the synthetic patch and human tissues in the host. We observed the growth of adipose-derived stem cells (ADSCs) cultured with polypropylene mesh in vitro. The results of flow cytometry showed that the expression of CD44, CD73, CD90, CD45, CD14 and CD34 was 98.54, 95.32, 98.49, 1.21, 3.01 and 2.14%, respectively. ADSCs were isolated from rabbit subcutaneous adipose tissue after collagenase digestion, filtration and centrifugation. The ADSCs of passage 3 were seeded onto the polypropylene mesh scaffolds...
June 2017: Experimental and Therapeutic Medicine
S K Swain, I Gotman, R Unger, E Y Gutmanas
In this paper, the processing and properties of iron-toughened bioresorbable β-tricalcium phosphate (β-TCP) nanocomposites are reported. β-TCP is chemically similar to bone mineral and thus a good candidate material for bioresorbable bone healing devices; however intrinsic brittleness and low bending strength make it unsuitable for use in load-bearing sites. Near fully dense β-TCP-matrix nanocomposites containing 30vol% Fe, with and without addition of silver, were produced employing high energy attrition milling of powders followed by high pressure consolidation/cold sintering at 2...
September 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Miklós Weszl, Krisztián László Tóth, Imre Kientzl, Péter Nagy, Dávid Pammer, Liza Pelyhe, Nihal E Vrana, Dieter Scharnweber, Cornelia Wolf-Brandstetter, Árpád Joób F, Eszter Bognár
OBJECTIVE: The objective of this study was to investigate the reproducibility, mechanical integrity, surface characteristics and corrosion behavior of nanotubular (NT) titanium oxide arrays in comparison with a novel nano-pitted (NP) anodic film. METHODS: Surface treatment processes were developed to grow homogenous NT and NP anodic films on the surface of grade 2 titanium discs and dental implants. The effect of process parameters on the surface characteristics and reproducibility of the anodic films was investigated and optimized...
September 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Sajjad Jafari, R K Singh Raman
A calcium phosphate coating was directly synthesized on AZ91D magnesium (Mg) alloy. Resistance of this coating to corrosion in a modified-simulated body fluid (m-SBF) was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Mechanical properties of the bare and coated alloy were investigated using slow strain rate tensile (SSRT) and fatigue testing in air and m-SBF. Very little is reported in the literature on human-body-fluid-assisted cracking of Mg alloys, viz., resistance to corrosion fatigue (CF) and stress corrosion cracking (SCC)...
September 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Kasey Catt, Huaxiu Li, Victor Hoang, Roland Beard, X Tracy Cui
Magnesium's complete in vivo degradation is appealing for medical implant applications. Rapid corrosion and hydrogen bubble generation along with inflammatory host tissue response have limited its clinical use. Here we electropolymerized a poly(3,4-ethylenedioxythiophene) (PEDOT) and graphene Oxide (GO) film directly on Mg surface. GO acted as nano-drug carrier to carry anti-inflammatory drug dexamethasone (Dex). PEDOT/GO/Dex coatings improved Mg corrosion resistance and decreased the rate of hydrogen production...
May 29, 2017: Nanomedicine: Nanotechnology, Biology, and Medicine
A Di Laura, H Hothi, J Henckel, I Swiatkowska, M H L Liow, Y-M Kwon, J A Skinner, A J Hart
OBJECTIVES: The use of ceramic femoral heads in total hip arthroplasty (THA) has increased due to their proven low bearing wear characteristics. Ceramic femoral heads are also thought to reduce wear and corrosion at the head-stem junction with titanium (Ti) stems when compared with metal heads. We sought to evaluate taper damage of ceramic compared with metal heads when paired with cobalt chromium (CoCr) alloy stems in a single stem design. METHODS: This retrieval study involved 48 total hip arthroplasties (THAs) with CoCr V40 trunnions paired with either CoCr (n = 21) or ceramic (n = 27) heads...
May 2017: Bone & Joint Research
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