Biological background of dermal substitutes

Dermal substitutes are of major importance in treating full thickness skin defects, both in acute and chronic wounds. In this review we will outline specific requirements of three classes of dermal substitutes:-natural biological materials, with a more or less intact extracellular matrix structure;-constructed biological materials, composed of specific biological components; and-synthetic substitutes, which can be synthesized on demand and can be modulated for specific purposes.Biological and clinical requirements will be translated to composition, physical structure, immunological properties and cell–matrix interactions of the various materials.Important properties like pore size, cell adhesion sites (e.g. RGD sequences), crosslinking, degradability and the presence of a basement membrane will be discussed for each of the different classes of materials.