A wound treatment dressing for leg ulcers, burns or necrosis. The dressing comprises a silver containment element, an exudate absorbing composition and a controllable electromagnetic element. The electromagnetic element is used to produce a pulsed magnetic field proximate to the silver containment element to control the number of active silver ions in the silver containment element. The silver containment element can be a non-woven structure of polymeric nanofibres with uniformly dispersed silver ion-loaded zirconium phosphate nanoparticles.
