Corrosion and fretting-corrosion processes are one of the most significant problems, involving medical construction elements. Friction under conditions of micro-movements often initiates the corrosion processes, which are intensified in the presence of human body fluids [1]. Wear effect is growing intensively especially in the joint elements (micro-contact areas). This results in formation of biomaterials wear products, which are harmful to human body. It is an undeniable fact, which has been confirmed by a number of clinical trials [2]. The released metal ions may cause local or systemic response of the organism, and may cause many diseases (inflammation, allergic reaction, metalosis). This can lead to failure of medical therapy. Fretting processes have attracted great attention, but we still lack information about dental organs. Metal-metal joints are mostly used in medical applications, but they are not always beneficial, due to increased risk of galvanic corrosion, which is why metal-plastic or metal-ceramics are becoming more popular. In this work, in vitro studies of fretting and fretting-corrosion processes of selected biomaterials in metal-alumina ceramics systems used in prosthetic and dental surgery were conducted. The studies were realized with the use of originally constructed pin-on-disc type fretting tester, combined with electrochemical measurement system. This apparatus allowed to conduct potentiodynamic corrosion tests in fretting conditions. Simultaneous registration of both processes allows for better analysis of actual phenomenon taking place in the living organism. Observations of samples' morphology by means ofscanning electron microscope (SEM) and confocal laser microscope (CLM) enable to determine the volume of material losses and thus to evaluate fretting and fretting-corrosion wear. Obtained results indicate that friction have significant impact on the durability of investigated biomaterials. Conducted tests are exploratory in nature and oriented, in particular, towards gaining better understanding of the destruction mechanisms of biomaterials and thus, extending the time of their reliable operation in medical applications.
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