Platelet-Rich Fibrin (PRF) is a second-generation biological concentrate that uses a patient’s own blood to accelerate the healing process. This technique involves isolating and concentrating specific components from a small blood sample to create a substance rich in growth factors and cells. The resulting material is a complex matrix containing high concentrations of platelets, white blood cells, and a dense, three-dimensional fibrin scaffold. Because PRF is derived solely from the patient’s own body, it is considered an autologous biomaterial, minimizing the risk of allergic reactions or disease transmission. This material harnesses the body’s natural regenerative capabilities to promote the repair of both soft and hard tissues.
The Biological Foundation
The effectiveness of Platelet-Rich Fibrin stems from its unique biological composition, specifically its concentration of platelets, white blood cells, and the fibrin matrix. Platelets, which are small cell fragments involved in clotting, function as storage houses for signaling proteins known as growth factors. These proteins include Platelet-Derived Growth Factor (PDGF), Transforming Growth Factor-beta (TGF-β), and Vascular Endothelial Growth Factor (VEGF). These factors stimulate cell migration, proliferation, and the formation of new blood vessels (angiogenesis).
The fibrin matrix is the distinguishing feature, forming a three-dimensional scaffold that structurally supports the healing process. This dense network traps the platelets and leukocytes, allowing for a slow and sustained release of growth factors over a period of up to a week or more. This differs from earlier platelet concentrates that release their factors in a rapid burst. This extended release profile enhances tissue regeneration and remodeling over time.
White blood cells (leukocytes) are incorporated into the PRF matrix and contribute to the healing environment. These cells play a role in the immune response and help regulate inflammation. Their inclusion contributes to the regenerative potential of the fibrin clot.
Preparation Process
The preparation of Platelet-Rich Fibrin begins with a simple draw of venous blood from the patient, typically 10 to 15 milliliters. This blood is immediately transferred into specialized sterile tubes that contain no chemical anticoagulants. The absence of an anticoagulant is deliberate, permitting the natural clotting cascade to begin as soon as the blood contacts the tube walls.
The tubes are then placed into a centrifuge and spun using a low-speed centrifugation (L-PRF) protocol. This gentle spin separates the blood components based on their density without fully separating the fibrinogen from the platelets and leukocytes. The controlled process allows fibrinogen to naturally polymerize into a dense fibrin clot, trapping the platelets and white blood cells.
After centrifugation, the resulting material settles into three distinct layers: red blood cells at the bottom, platelet-poor plasma at the top, and the PRF clot in the middle. This yellow, jelly-like PRF layer is carefully extracted and can be used immediately in various forms, such as a solid membrane, a plug, or a liquid injectable. The solid clot is often compressed to form a durable membrane for grafting procedures, while the liquid form (Injectable PRF or i-PRF) is used for injections.
Therapeutic Applications
Platelet-Rich Fibrin is widely utilized across several medical disciplines due to its ability to stimulate tissue repair and accelerate recovery. Its most established application is in Oral and Maxillofacial Surgery, where the solid PRF membrane or plug is used extensively. PRF is routinely placed into extraction sockets following tooth removal to promote bone and soft tissue healing, a procedure known as socket preservation.
In complex dental procedures, such as sinus lifts and bone grafting for dental implants, PRF is mixed with bone graft material to form a cohesive, moldable substance often referred to as “Sticky Bone.” The fibrin scaffold acts as a “biological connector,” stabilizing the graft particles and attracting osteoprogenitor cells necessary for new bone formation. This enhances bone density and integration, which is crucial for the success of dental implants.
Aesthetic Medicine uses PRF, primarily the injectable or liquid form, for skin rejuvenation, volume restoration, and hair restoration. When injected into the skin, the fibrin matrix acts like a temporary natural filler, supporting the tissue while growth factors stimulate collagen and elastin production. For hair loss, the concentrated growth factors are delivered directly to the scalp to encourage the growth phase of hair follicles.
PRF is also explored in Orthopedics for soft tissue repair and joint injections. The slow release of growth factors within the fibrin scaffold may help regenerate damaged tendons, ligaments, and cartilage. The anti-inflammatory properties of the leukocyte-rich concentrate also contribute to reducing discomfort and promoting healing in injured joints.
Distinguishing PRF from PRP
Platelet-Rich Fibrin represents a second-generation evolution of Platelet-Rich Plasma (PRP), its predecessor. The two differ significantly in their composition and regenerative mechanism. The preparation process for PRP requires the addition of an anticoagulant, such as citrate, to prevent clotting during centrifugation. PRF, in contrast, is prepared without chemical additives, relying on the natural clotting process.
The fundamental difference lies in the final structural form: PRP is a liquid solution, while PRF forms a dense, three-dimensional fibrin matrix. This matrix allows PRF to release its concentrated growth factors in a slow, sustained manner over a period of days to a week. PRP typically releases its growth factors in a rapid burst within a few hours of application, leading to a shorter duration of biological activity.
PRF preparations also contain a higher concentration of leukocytes, or white blood cells, which are retained within the fibrin network. These white blood cells contribute to the anti-infectious and immune-modulating effects of PRF. The structural and cellular differences mean PRF provides both a scaffold and a sustained supply of healing factors.