Introduction: The key component of the prosthesis is the socket. The socket is in direct contact with the skin of the stump, which gives an option for bacteria to transfer from skin to material surface. The most common type of bacteria in permanent microbiota of the skin are staphylococci, among which is the bacterium Staphylococcus epidermidis. The adhesion of bacteria to the surface is influenced by various factors, such as roughness, surface charge and hydrophobicity of the material surface. Purpose: To determine how roughness, surface charge and hydrophobicity of the material surface influence the degree of adhesion of Staphylococcus epidermidis to materials that are in contact with the stump and compare them with each other. Methods: Four different materials used for the production of sockets and liners were used for the research: acrylic resin, mixture of ethylene-vinyl acetate and low-density polyethylene, silicone and thermoplastic elastomer. We measured surface roughness of the material surface, contact angle for determining the hydrophobicity of the surface and zeta potential to determine surface charge. For the research we used the standard bacteria Staphylococcus epidermidis and determined growth curve of the bacteria. To determine the adhesion of the bacteria to the materials, the sterile materials were immersed in the culture medium of the Staphylococcus epidermidis bacterium and were incubated for 10 hours. The surfaces were then fixed and dried. Through scanning electron microscope we produced surface images, counted bacteria on the image and calculated proportion of bacteria coverage on the surface. Results: The highest hydrophobicity was measured on silicone, followed by acrylic resin, thermoplastic elastomer and mixture of ethylene-vinyl acetate and low-density polyethylene. The roughness was the highest on thermoplastic elastomer followed by mixture of ethylene-vinyl acetate and low-density polyethylene, silicone and least on acrylic resin. The smallest zeta potential was measured on mixture of ethylene-vinyl acetate and low-density polyethylene, folowed by acrylic resin, and silicone. Thermoplastic elastomer was not measured. Adhesion was the highest in thermoplastic elastomer and silicone respectively, and visibly less on mixture of ethylene-vinyl acetate and low-density polyethylene and least on acrylic resin. Discussion and conclusion: The results showed that roughness of the surface had the greatest effect on adhesion on thermoplastic elastomer and acrylic resin. High adhesion on silicone can be attributed to the high hydrophobicity of the material. Relatively small adhesion on mixture of ethylene-vinyl acetate and low-density polyethylene could be the result of the content of silver ions.
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