MTS-Science – Acute wounds are caused exogenously by traumatic (e.g. mechanical, chemical, thermical) or iatrogenic (e.g. surgical) injury. In general, they are sharply limited and heal within short time without major complications. If there is no progress in healing after more than 4 weeks, they are referred to as chronic wounds, which arise from disturbed wound healing processes due to other underlying diseases, like diabetes mellitus, venous diseases, circulation problems or disorders of the immune system. Chronic wound margins are imprecise and in the majority of cases they are infected. Chronic wounds have not completed the process of healing (restoring tissue loss and skin function), have not responded to initial treatment or persist despite appropriate care.