Biologics in wound healing: repair versus regeneration

Biologics use in treating wounds has grown exponentially in recent years. Many of the current devices enhance natural repair mechanisms; however, the quest for tissue regeneration is becoming clearer. No single biologic can provide all the needed components for dermal regeneration. Growth factor or cytokine delivery devices appear to be too nonspecific to go beyond improving repair mechanisms and perform more like dressings because of their lack of mechanical structure and biocompatibility. Scaffolds that are biocompatible show promise and act more like grafts that can integrate with host tissue and show histological evidence of the beginnings of regeneration. Finally, stem cells have demonstrated promise but cannot reach their full regenerative potential unless they are seeded on a biocompatible scaffold. The scaffold used must have the mechanical and structural features of the original tissue or organ to aid in regeneration. Current researchers in tissue and organ regeneration have embraced the benefits of seeding stem cells on this type of scaffold. They also have demonstrated the benefit of signaling host cells to migrate into the same biocompatible scaffold through both chemotactic and mechanical signaling. This review focuses on the different approaches of biologic categories in wound healing and the progress of the individual research tracts that are attempting to change wound healing from secondary-intent healing and tissue repair to tissue regeneration.