Clinical Comparison of Platelet Rich Fibrin and Collagen Dressing in the Management of Palatal Wounds:A Randomized Controlled Clinical Trial.

The hard palate is a common source of soft-tissue grafts (STG) for periodontal and perio-plastic surgery procedures.The main drawbacks of such techniques are the two surgical sites,pain and discomfort experienced by the patient, especially at the donor sites and potential for postoperative bleeding from the donor area which heals by secondary intention resulting in longer healing time and discomfort in the first 2 postoperative weeks.Palatal donor site healing occurs through fibroblast proliferation, collagen synthesis, angiogenesis, and contraction of the wound. In addition, revascularization, immunity, and epithelial cell proliferation are crucial factors for optimal wound healing.In an endeavor to accelerate the healing process and to reduce prolonged bleeding and pain caused by the palatal wound, materials such as hemostatic agents (e.g., absorbable synthetic collagen, absorbable gelatin sponge, cyanoacrylate, oxidized regenerated cellulose, ferric sub sulfate)and more recently platelet concentrate have been used.Collagen dressings have extensively been used in dentistry due to its ability to achieve hemostasis, being chemotactic to fibroblasts and platelets and inducing mesenchymal proliferation and differentiation.These dressing control bleeding and stabilize blood clots as well as protect the wound bed while accelerating the healing process. Platelet-rich fibrin (PRF) is an immune and platelet concentrate collecting on a single fibrin membrane all the constituents of a blood sample favorable to healing and immunity.It has a rich source of growth factors and its application has been reported as an effective way to induce tissue response and regeneration. There are at least 60 different biologically active substances present in platelets which are involved in tissue repair mechanisms such as chemotaxis, cell proliferation and differentiation, angiogenesis, intracellular matrix deposition,immune modulation, antimicrobial activity, and remodeling. Platelet concentrates used in palatal wound healing have growth factors, such as fibroblast growth factor-basic (FGFb),vascular endothelial growth factor (VEGF), and angiopoietin and platelet-derived growth factor (PDGF) which are the main angiogenesis soluble factor. This could facilitate faster healing by exerting a positive influence on the mitogenesis of wound healing cells, angiogenesis, and promotion of cellular differentiation at the wound site.Platelet-rich fibrin supports the three main keys of wound healing mechanism that is “angiogenesis,” “immunity,” and “epithelial proliferation” and thus has implicated its use to protect open wounds and accelerate healing