Technology and product reviews These multiple procedures can be stressful
for the patient and are inefficient, both in terms of cost and resources[5]
.
To circumvent this limitation, MatriDerm is an engineered dermal template specially developed to provide a one-step grafting procedure without the disadvantages of diminished take-rate.
BASIC WOUND HEALING Superficial epidermal injuries heal by re- epithelialisation from existing keratinocytes or keratinocyte stem cells that are present in the wound bed. Scarring in such injuries is minimal. If the injury extends to the superficial layer of the dermis, it is possible that regeneration of the epidermis will occur without surgical intervention provided there are a sufficient number of keratinocyte stem cells. If epidermal keratinocytes are completely lost, repair may occur from the epithelial stem cells that are present in the hair follicles and/or sweat glands in the deep layers of the skin (dermis). When the injury extends to the deeper layers
References 3. Enoch S, Roshan A, Shah M.
Emergency and early management of burns and scalds. Br Med J 2009; 338: 1087.
4. A Sarkar, S Tatlidede, SS Scherer, DP Orgill, F Berthiaume. Combination of stromal cell-derived factor-1
and collagen-glycosaminoglycan scaffold delays contraction and accelerates reepithelialization of
dermal wounds in wild-type mice. Wound Repair Regen 2011; 19(1): 71–79.
5. Haslik W, Kamolz LP, Nathschläger G, Andel H, Meissl G, Frey M. First experiences with the collagen- elastin matrix MatriDerm® as a
dermal substitute in severe burn injuries of the hand. Burns 2007; 33(3): 364–68.
6.Wood BC, Caputy G. Skin grafts. 2011; Available at: http://
emedicine.medscape.com/ article/1295109-overview (accessed 4 May, 2011)
(including the hypodermis or muscle), the injured surface is depleted of its keratinocytes, fibroblasts and any stem cells. Thus surgical excision of the involved tissue is frequently required along with reconstruction using STSGs, which contain all the epidermis and superficial parts of the dermis, thereby transferring self-renewing keratinocyte stem cells to the recipient area. Deep dermal and full-thickness skin injuries usually require surgical excision and grafting. In such deep wounds, an ‘ideal’ skin substitute would provide immediate replacement of both these essential layers (epidermis and dermis), therefore the ideal skin substitute is defined as one that[6]
:
n Resists infection n Withstands shearing forces n Lacks antigenicity n Is conformable to irregular wound surfaces
n Is flexible and durable n Closes the wound immediately n Rejuvenates new skin n Is synthetic and bio-absorbable.
With advances in tissue engineering and biotechnology, there are several skin substitutes — both in use at present and in development — that are employed for the replacement or reconstruction of one or both layers of the skin.
36 Wounds International Vol 3 | Issue 2 | ©Wounds International 2012
TISSUE-ENGINEERED DERMAL CONSTRUCTS Tissue-engineered dermal constructs (TEDC) are a heterogeneous group of products that are aimed at replacing, either temporarily or permanently, the form and function of lost dermis. These products provide an alternative to the standard wound coverage in circumstances when established wound dressings are not appropriate. TEDCs consist of a micro-engineered,
biocompatible polymer matrix produced by tissue engineering. If used in combination with cellular and/or extracellular elements, such as collagen, they result in a biosynthetic product. Synthetic and biosynthetic constructs are intended to be stable, biodegradable and are aimed at providing an adequate environment for the regeneration of tissue. MatriDerm is a class III product which
works as an implant. The collagen-elastin matrix is absorbed in approximately six weeks by replacement of autologous cells and tissue. As such it acts as a scaffold for tissue reconstruction (neodermis). Any skin substitute should maintain its
three-dimensional structure for a minimum of three weeks to allow in-growth of blood vessels and fibroblasts, as well as coverage by epithelial cells. Biodegradation begins after this period and the whole process should occur without a significant ‘foreign body’ reaction, since this may lead to increased scarring. Depending on their composition, both
synthetic and biological skin substitutes can be divided into dermal, epidermal or dermo- epidermal replacements. Sustainability is an additional factor, depending on whether a skin substitute is temporary or permanent: n Temporary skin substitutes: provide transient physiologic wound closure, including protection from trauma, provision of a barrier to bacteria and pathogens, and maintenance of a moist wound environment, until repair of the damaged tissue is complete
n Permanent skin substitutes: as the name suggests these are designed to provide permanent wound closure, replace lost skin components (epidermis, dermis or both), and integrate with the recipient tissue.
HISTORY OF ENGINEERED DERMAL CONSTRUCTS An allograft is a tissue or organ that is transplanted from one individual to a member
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