Frank Pude

Experimental in-vitro bone cements disintegration with ultrasonic pulsating water jet for revision arthroplasty

The paper deals with the study of using the selective property of ultrasonic pulsating water jet for the disintegration of the interface created by bone cement between cemented femoral stem and trabecular bone tissue as a potential technique for revision arthroplasty. Six types of commercial bone cements based on Polymethyl Methacrylate were used for investigation. The cements were mixed using the DePuy - SmartMix® CTS / vacuum mixing bowl. Mechanical properties of hardened bone cements were determined by nanoindentation. The bone cement samples were disintegrated using the pulsating water jet technology. The water pressure varied between 8÷20 MPa. A circular nozzle with an orifice diameter of 0, 7 mm was used for water jetting. The stand-off distance from the target material was 2 mm and the traverse speed 1 mm/s. The volume of material removal and depth of created traces were measured by MicroProf FRT optical profilometer. The results positively support an assumption that pulsating water jet has a potential to be a suitable technique for the quick and safe disintegration of bone cement during revision arthroplasty.

FEASIBILITY STUDY ON THE USE OF FRACTAL ANALYSIS FOR EVALUATING THE SURFACE QUALITY GENERATED BY WATERJET

Original scientific paper The paper presents the fractal analysis application for a simple evaluation of the quality of waterjet treated surfaces, especially after abrasive waterjet cutting. This analysis will enable the elimination of subjective assessments of treated surfaces. This will ensure a clear estimate of the quality of the surface and the ability to objectively compare the quality of the cutting edge obtained by using different cutting parameters.

Surface structuring of zirconium-based bulk metallic glasses using ultrashort laser pulses

A technique for structuring the surface of a bulk metallic glass (BMG) via scanning with a beam of laser pulses in the pico- and femtosecond time regime is presented. Specimens were characterized by various techniques to analyze the effects of ultrashort laser pulses on the amorphous matrix. Broadly varying surface structures, with roughness parameters in the range of Ra = 0:066 to 0:329 μm, measured using white light interferometry (WIM) and optical 3D microscopy, were produced. These techniques could be useful for fabricating biomedical implants from BMGs. As proof of principle, a patterned grid, designed for evaluating bone cell response to different surface structures, are produced.