Surface modification of artificial implants by hybrid nanolayers - antimicrobial surface finishing and strength tests.

INTRODUCTION: The aim of this work is the evaluation of surface modification in surgery of normally used hernia implants and thus improving their antimicrobial properties. The modification consisted of applying hybrid nanolayers with immobilized antiseptic substances (metal cations of Ag, Cu and Zn) by sol-gel method which ensures prolonged effect of these substances and thus enables a greater resistance of the implant towards infection. In this work attention is drawn to the issue of applying hybrid nanolayers, activation of mesh surfaces by physical plasma modification or UV C radiation and influence of these modifications on the mechanical properties of the final meshes. Next work will continue concentrating on the issue of antimicrobial efficacy and eventual toxicity of the prepared layers.

MATERIALS AND METHODS: Present day materials of the most commonly used types of implants for reconstruction of the abdominal wall in surgery (PP, PES, PVDF) were tested. Optimum conditions of application of nanolayers by sol-gel method and their thermal stabilization were examined first. Surface modification was verified by scanning electron microscope. The surface of implants was first activated for better adhesion by plasma treatment or UV radiation after preliminary tests. Maximum strength and ductility after activation and hybrid nanolayer modification were objectively measured on a universal Testometric tensile testing machine.

RESULTS: The results of surface activation of the meshes (by both plasma treatment or UV C radiation) provided similar and satisfactory results, particular conditions differed based on the type of material of the mesh. Usage of antimicrobial sol AD30 diluted by isopropyl alcohol in 1: 1 proportion appear to be optimal. All tested cases of meshes activated by plasma modification or UV C radiation and with applied nanolayer concluded in a slight reduction of mechanical properties in modified meshes in comparison with the original ones. However, a slight reduction of test values were not of clinical importance.

CONCLUSION: It was verified that surface modification of implants by sol-gel method is effective and technically possible, providing hopeful results.