Ureteral stents, also known as kidney stents or uretic stents, are usually made of metals or plastics of increasing and decreasing polymer density, according to PolySciTech. As of August 2015, however, research is underway to develop a biodegradable ureteral stent capable of degrading away in 2-weeks time. Research focuses on utilizing a combination of biodegradable polymers and water soluble polymers to create a stent that is both flexible and capable of seamless degradation.
Two different metal ureteral stents are available and used for deobstructing the ureter, notes the Indian Journal of Urology. These include Memokath 051 and Allium URS. Memokath 051 has a nitinol-made bare metal closed coiled body and a thermo-expandable bell-shaped end for anchoring. The Allium URS has a nitinol-made skeleton covered with a strong but thin proprietary polymer membrane, which gives it a tubular shape.
Other materials may be added to the skeletal structure of a kidney stent. As of August 2015, novel coatings and drug-eluting materials are being vetted by medical professionals in an effort to reduce the most common problems associated with semi-permanent ureteral devices, states Therapeutic Advances in Urology. These complications include bacterial adhesion, encrustation, and biofilm formation on the surface of the device.