A dressing that comprises a contact layer for contacting a wound, with the contact layer including silicone a foam-based hydrophilic middle layer that carries a metal-based antimicrobial agent and a backing layer that prevents moisture within the dressing from escaping into the air through evaporation. Silicone in the contact layer interacts with the wound to minimize the appearance of scar tissue. Moisture, either applied beforehand or from the wound exudate, travels through the porous contact layer into the foam middle layer. There, the moisture acts to release metal ions from controlled-release mechanisms, such as zeolites containing the metal ions. The ions then travel within the moisture into the wound, where they act to kill bacteria and other infectious microorganisms and to prevent infections from gaining a foothold. Many embodiments, for the metal-based antimicrobial agent, use silver ions or a combination of silver ions and other metal ions.