Ureteral double-J stents performances toward encrustation after long-term indwelling in a dynamic in vitro model.

Three different single-lumen double-J ureteral stents of different materials were studied and compared after the insertion into a dynamic in vitro model with sterile artificial urine up to 6 months. The aim was to evaluate, at selected time steps of 1, 3, and 6 months, the material performances of the stents in preventing the formation of inorganic encrustations. Morphological, compositional, and qualitative analyses were carried out both before stent insertion and after stent permanence for the different time steps, showing an increasing level of encrustation which remains particularly low in the case of two polyurethane stents. Mechanical tests show that both the polyurethane stents and the chitosan one do not decrease the tensile strength after 6 months of indwelling. Evaluation of the wetting behavior of the stent outer surfaces indicates a hydrophilic behavior in most of the cases, which is generally preserved after immersion in artificial urine for the different time steps. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2244-2253, 2017.