Decellularized allogeneic dermis (also called Jieya dermis) is a dermal substitute that has emerged in recent years and has been experimentally studied and applied to clinical repair in various disciplines such as burn plastic surgery, otorhinolaryngology-head and neck surgery, periodontology, meningeal repair, etc. Features of decellularized allogeneic dermis Decellularized allogeneic dermis is the use of allogeneic natural skin through unique processing technology to remove the epidermis of allogeneic skin, and completely remove all the cellular components of the dermis on the basis of intact three-dimensional structure of the dermis, after transplantation can be used as a good scaffold for epithelial cells, fibroblast migration, neovascularization. It does not cause immune rejection in the recipient after transplantation. Biological properties of decellularized allogeneic dermis Decellularized allogeneic dermis is a natural extracellular matrix, the structure of decellularized allogeneic dermis is a collagen meshwork, the three-stranded helix structure of collagen molecule is very stable, not hydrolyzed by general proteases, but can be hydrolyzed by collagenase, the degradation of collagen is slow, the half-life of collagen varies from several weeks to several years. The immune response generated by allogeneic dermis mainly acts on the cellular components such as epidermal cells, fibroblasts and endothelial cells in the dermis, while the non-cellular components of the dermis such as extracellular matrix proteins and glial principles are relatively inactive. As a kind of allogeneic dermis, the cellular components, sweat glands, sebaceous glands and type I and II cytocompatibility antigens have been completely clarified, and will not induce specific foreign body reactions against allogeneic tissue grafts. The basement membrane complex is preserved in decellularized allogeneic dermis, forming two surfaces, basement membrane and dermis. The dermal surface facilitates rapid vascularization of decellularized allogeneic dermis, while the basement membrane surface provides a natural plane for the migration and colonization of epithelial cells, which facilitates epithelialization of decellularized allogeneic dermis. The decellularized allogeneic dermis serves as a dermal substitute to provide sufficient dermal tissue to the wound surface, thereby reducing scar formation and contracture. The amount of scar formation and the degree of contracture are inversely proportional to the amount of dermis in the implanted skin. The extracellular matrix in the decellularized allograft dermis is structurally intact and can provide a good scaffold for the regeneration of tissue cells to convey biological information, and the extracellular matrix protein can promote the attachment and proliferation of epidermal cells. Fibroblasts transplanted from the base of the trauma into the decellularized allogeneic dermis have the ability to produce a mature matrix. It can be cut, overlapped, rolled into rolls, or made into micronized powder for intradermal or subcutaneous injection, and fibroblast migration and collagen deposition can be seen. The metabolic requirements of decellularized allogeneic dermis are very low. Vascularization of decellularized allogeneic dermis results in varying degrees of resorption. The cell-free nature of decellularized allogeneic dermis greatly reduces the possibility of inflammatory reactions, and after transplantation the body treats it as autologous tissue, gradually modifying it to resemble autologous tissue.