Wyniki 1-1 spośród 1 dla zapytania: authorDesc:"Tomasz Ogiński"

Corrosion resistance of fixed orthodontic appliance components in Ringer's solution DOI:10.15199/40.2017.7.3

  The metallic materials, due to their ability to carry mechanical loads, such as tensile stresses and bending moments, are most often used in prosthetic and orthodontic treatment in dentistry [26]. Their main disadvantage is their susceptibility to all kinds of corrosion caused by the action of saliva or body fluid [1, 10]. The aggressiveness of the media is largely extent due to the presence of chloride ions. Also the body’s peculiar characteristics may significantly contribute to the aggressiveness of the body fluids (e.g. in the oral cavity) [6, 14]. The chemical composition of metallic materials determines their resistance to corrosion and so their applicability as implants. The maximum tolerable rate of corrosion of such materials cannot exceed 2.5·10-4 mm/year [3-5]. Corrosion damage to chromium-nickel-molybdenum steel implants [3, 17] is caused not only by electrochemical corrosion, but also by transcrystalline corrosion, pitting corrosion, crevice corrosion and fatigue corrosion [4]. Pitting corrosion predominates in places where the dynamic loads do not act on the implant while stress corrosion and fatigue corrosion predominate in the implant’s areas subjected to cyclic loading. The multiplicity of corrosion factors occurring within the body environment makes it difficult to determine the causes of corrosion damages [7, 14, 21, 25, 28]. Ions of metals, such as chromium and nickel, are released as a result of corrosion, posing a hazard to health and life as they affect on many basic life processes [10, 27]. An excessive concentration of stainless steel constituent elements (e.g. Fe, Cr, Ni, Mo, Mn) in body fluids causes poisoning [15, 16]. Chromium is known to facilitate glucose assimilation, but when present in excess, it has toxic effects, such as damage to parenchymatous tissues and organs as well as allergies [18]. Nickel and molybdenum belong to the group of carcinogenic and allergenic [...]

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