The ASTM Standard Guide for Classification of Therapeutic Skin Substitutes is a highly useful reference that includes many of the definitions needed to understand, classify, and differentiate products originally discussed as skin substitutes. The document was originally approved in 2003 and updated in 2006 and 2008, reflecting the need to keep the classifications and definitions current and responsive to changes in the field. Since the inception of this guide, several major developments have taken place in skin repair and regeneration that are relevant to the documents classifications and scope. An important example is that many of the products currently being used for the treatment of skin wounds and burns do not resemble skin tissue and do not act to substitute for or mimic it. Instead, these products consist of cells and/or tissue-based constructs that are introduced into/onto skin wounds or burns where they support the synthesis of new skin tissue in vivo. As such, these products do not really qualify as skin substitutes and thus the workgroup has proposed a new title for this class: Cellular and/or Tissue-based Products for wounds (CTPs). A second major development is that many of the existing/in development CTPs are primarily used, or are targeted for use, as treatments for chronic wounds. Such wounds are not typically treated with grafts, although the Scope section of the current document specifies its purview as products that can be substituted for tissue grafts. Indeed, grafts are used as the reference point throughout the entire document, which is relevant for burns and acute surgical wounds, but not for chronic wounds. Therefore, the options appear to be 1) create an entirely new document for chronic wounds or 2) amend the current document to be more inclusive. Given the large amount of overlap that two such documents would inevitably exhibit, we favor the latter option. In recognition of the use of these products for the treatment of chronic wounds, the workgroup has proposed a number of new definitions pertaining to chronic wounds or ulcers throughout. Another area of concern is the need to distinguish CTPs from surgical dressings. In the existing document, differences between these two categories of products are not considered, leading to confusion about whether many of the products should be considered CTPs (old term skin substitutes) or surgical dressings. The workgroup has attempted to clarify the distinction throughout the document.
Keywordsskin graft; skin substitutes; surgery; tissue engineering; tissue regeneration; wound healing; Classification (standards)--medical/surgical applications; Skin graft/substitutes; Skin; Surgical tissue applications; TEMPs (tissue engineered medical products); Therapeutic skin substitutes; Tissue repair/regeneration; Wound healing;
Mary Ann Chapman
Draft Under Development