Study of heat-setting treatment for biomedical polydioxanone stents

This paper presents a study of heat-setting treatment on tubular polydioxanone stents which can be used as intestinal implants. Two PDO monofilaments with linear densities of 100 ± 2 and 150 ± 2 tex respectively were used for producing a set of weft-knitted tubular stents using a small-diameter, circular weft knitting machine. The heat-setting treatment was used for the stents to restore a tubular shape. The physical, mechanical and thermal properties of the stents were examined before and after the heat-setting treatment. The results of mechanical testing illustrated that the prototype stents in this work could achieve higher radial forces than Wall stents and Z stents on the market. The heat setting with temperature of 80℃ and time of 5 min were found to be more appropriate for the stents. In conclusion, the stents were successfully developed and have potential application for the treatment of intestinal stenosis or obstruction.