**1. Introduction**

The skin is the largest organ of the body and is responsible for many essential functions that no skin substitute has been able to fully replicate to date. Skin substitutes can be defined as any material used to provide biologic wound coverage on a temporary or permanent basis. Skin substitutes may be differentiated from simple, inert, wound dressings in that they possess properties that allow them to enhance repair of skin after injury, expedite regeneration and improve scar quality [1–3].

Epidermal and superficial partial thickness burns have the potential to heal by epidermal regeneration from adnexal nests of epidermal stem cells with minimal scarring, provided the burn wound remains protected and free from infection. Conventional management of debrided deep dermal and full thickness burns has been to achieve wound closure with autologous skin grafts since they were first introduced

in the nineteenth century. Early wound closure minimises the severity of scarring and functional impairment caused by permanent dermal loss. However, autologous skin graft donor site availability is frequently limited in major burn patients, particularly when the total body surface area of burn (TBSA) exceeds 25%. Donor site morbidity from skin autograft harvest includes acute physiological insult to the burn patient, blood loss, pain and additional wounding and scarring. Allograft and xenografts are less desirable than autograft due to inherent issues with delayed graft rejection and risk of infection.

A vast array of skin substitutes have been developed through advances in tissue engineering and biomaterials. Skin substitutes have not yet eliminated the requirement for autologous skin grafting in deep or full thickness burns. However, they have the potential to circumvent some issues associated with autologous graft in terms of availability or lack thereof, donor site morbidity and failure to adequately replace dermal elements in deeper injuries. Skin substitutes can provide clinical benefits in terms of wound healing that have been outlined, as follows [4]:


Simplified classification systems can aid clinicians in selection of appropriate skin substitutes for burn wound reconstruction. Robust classifications can also benefit research efforts by allowing comparison of outcomes across a growing range of available skin substitutes, categorised based on their properties.
