Urinary encrustation of alloplastic materials.

Currently, all alloplastic materials placed within the urinary tract are susceptible to encrustation, and devices made from these biomaterials are prone to the associated complications. Encrustation is affected by such surface properties as roughness and irregularity, hydrophobicity and wetability, charge, polymer chemistry, and coatings. The composition of the surface may also influence reactivity at the interface. A raised urinary pH as a result of infection with urease-producing bacteria is an important mechanism of encrustation, but encrustation can take place in the absence of infection. Individual variations in the risk of encrustation have been identified. Better device designs are required, as are better models for examining biomaterials and biofilm formation. With a coordinated multidisciplinary approach and adequate resources, we may solve the problem of encrustation, which has such an adverse effect on patient quality of life and on healthcare costs.