手术器械生锈原因分析及预防对策

手术器械的锈蚀存在很大的安全隐患,轻则影响器械的使用性能,重则可引发医院感染或直接导致器械报废[1].为了保障医疗安全,延长器械的使用寿命,防止医院感染的发生,我院消毒供应中心于2010年5月开始实行手——供一体化.通过对器械锈蚀的可能原因进行分析,并采取相应的干预措施后,手术器械的锈蚀现象得到明显改善,现将体会报告如下.     

Evaluation of the inhibitive effect of Diospyros kaki (Persimmon) leaves extract on St37 steel corrosion in acid medium

A study was conducted to assess the inhibitive effect of Diospyros kaki leaves extract on St37 steel corrosion in 0.1 M HCl solution. Electrochemical (PDP, EIS, DEIS), chemical, and surface morphological screening (SEM, EDS, FTIR) techniques were used in the study. Results show that D. kaki leaves extract is an excellent inhibitor for St37 steel in HCl solution. Maximum inhibition efficiency of 91% was afforded by the highest studied concentration of the extract from PDP measurements. PDP results reveal that the extract components act principally as cathodic type inhibitor suppressing the reduction of hydrogen ions in the cathodic region of the metal. DEIS results show that the studied systems exhibit non-stationary character and the adsorbed extract components were stable particularly at long exposure time. SEM, EDAX, and FTIR results support experimental results that components of D. kaki leaves extract were adsorbed on St37 surface.     

Enhanced antibacterial properties,biocompatibility, and corrosion resistance of degradable Mg-Nd-Zn-Zr alloy

Magnesium (Mg), a potential biodegradable material, has recently received increasing attention due to its unique antibacterial property. However, rapid corrosion in the physiological environment and potential toxicity limit clinical applications. In order to improve the corrosion resistance meanwhile not compromise the antibacterial activity, a novel Mg alloy, Mg–Nd–Zn–Zr (Hereafter, denoted as JDBM), is fabricated by alloying with neodymium (Nd), zinc (Zn), zirconium (Zr). pH value, Mg ion concentration, corrosion rate and electrochemical test show that the corrosion resistance of JDBM is enhanced. A systematic investigation of the in vitro and in vivo antibacterial capability of JDBM is performed. The results of microbiological counting, CLSM, SEM in vitro, and microbiological cultures, histopathology in vivo consistently show JDBM enhanced the antibacterial activity. In addition, the significantly improved cytocompatibility is observed from JDBM. The results suggest that JDBM effectively enhances the corrosion resistance, biocompatibility and antimicrobial properties of Mg by alloying with the proper amount of Zn, Zr and Nd.     

Hypersensitivity to Titanium: A Less Explored Area of Research

Titanium is considered as an excellent biocompatible metal and it is used in implant dentistry. Literature suggests that Ti can induce clinically relevant hypersensitivity and other immune dysfunctions in certain patients chronically exposed to this reactive metal. At the same time, no standard patch test for Ti has so far been developed, and positive reactions to Ti have therefore only rarely been demonstrated with skin testing. This article reports about the corrosion of dental implants, their significance when hypersensitivity is present, and the literature available till date regarding hypersensitivity of titanium.     

The Corrosion Resistance of Composite Arch Wire Laser-Welded By NiTi Shape Memory Alloy and Stainless Steel Wires with Cu Interlayer in Artificial Saliva with Protein

In this paper, the corrosion resistance of laser-welded composite arch wire (CoAW) with Cu interlayer between NiTi shape memory alloy and stainless steel wire in artificial saliva with different concentrations of protein was studied. It was found that protein addition had a significant influence on the corrosion behavior of CoAW. Low concentration of protein caused the corrosion resistance of CoAW decrease in electrochemical corrosion and immersion corrosion tests. High concentration of protein could reduce this effect.     

氟离子对纯钛表面微弧氧化膜耐腐蚀性能的影响

目的:研究在含氟模拟体液中纯钛表面微弧氧化膜的耐腐蚀性能。方法:制备纯钛试件,利用电化学方法测量纯钛表面微弧氧化处理后的极化曲线和交流阻抗。电化学实验溶液体系分为2组(n=4),分别为不含氟模拟体液组(A组)和加NaF模拟体液组(B组)。结果:和不含氟模拟体液组比较,含氟组中微弧氧化处理后试样的自腐蚀电位、自腐蚀电流密度增大和交流阻抗减少,差异均有显著性(P<0.01)。结论:氟离子可以降低纯钛微弧氧化后的耐腐蚀性能。     

Corrosion of metal orthodontic brackets and archwires caused by fluoride-containing products: Cytotoxicity,metal ion release and surface roughness

Purpose

The aims of this study were to determine the cytotoxicity, metal ion release and surface roughness of metal orthodontic appliances after immersion in different fluoride product solutions.

A layer-by-layer approach to natural polymer-derived bioactive coatings on magnesium alloys

The development of polyelectrolyte multilayered coatings on magnesium alloy substrates that can be used for controlled delivery of growth factors and required biomolecules from the surface of these degradable implants could have a significant impact in the field of bone tissue regeneration. The current work reports on the fabrication of multilayered coatings of alginate and poly-l-lysine on alkaline- and fluoride-pretreated AZ31 substrates using a layer-by-layer (LbL) technique under physiological conditions. Furthermore, these coatings were surface functionalized by chemical cross-linking and fibronectin immobilization, and the resultant changes in surface properties have been shown to influence the cellular activity of these multilayered films. The physicochemical characteristics of these coated substrates have been investigated using attenuated total reflectance Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Cytocompatibility studies using MC3T3-E1 osteoblasts show that the fluoride-pretreated, cross-linked and fibronectin-immobilized LbL-coated substrates are more bioactive and less cytotoxic than the hydroxide-pretreated, cross-linked and fibronectin-immobilized LbL-coated samples. The in vitro degradation results show that the multilayered coatings of these natural polysaccharide- and synthetic polyamino acid-based polyelectrolytes do not alter the degradation kinetics of the substrates; however, the pretreatment conditions have a significant impact on the overall coating degradation behavior. These preliminary results collectively show the potential use of LbL coatings on magnesium-based degradable scaffolds to improve their surface bioactivity.     

过氧化氢对银汞合金电化学腐蚀性能的实验研究

目的研究不同浓度过氧化氢对银汞合金电化学腐蚀性能的影响。方法采用电化学工作站的开路电位、电化学阻抗谱及动电位极化曲线法对不同浓度过氧化氢（0%、3.6%、10%及30%）浸泡24h后的牙科银汞合金在人工唾液中的腐蚀行为进行比较。结果 10%和30%过氧化氢浸泡后的银汞合金在人工唾液中开路电位较快地达到了一个稳定的值,且开路电位较短时间变化范围大小顺序为0%组〈3.6%组〈10%组〈30%组;不同浓度过氧化氢浸泡后的银汞合金在人工唾液中的等效电路极化电阻大小顺序为：0%组〉3.6%组〉10%组〉30%组,与动电位极化曲线腐蚀电位（Ecorr）结果一致;而自腐蚀电流密度（Icorr）结果为：0%组〈3.6%组〈10%组〈30%组。结论随着过氧化氢浓度的升高,银汞合金在人工唾液中的耐腐蚀性能越来越差。