What is the difference between platelet-rich plasma (PRP) and leukocyte platelet-rich fibrin (L-PRF) in terms of treatment outcomes?

Platelet-Rich Plasma vs Leukocyte Platelet-Rich Fibrin: Key Differences and Clinical Implications

Leukocyte- and Platelet-Rich Fibrin (L-PRF) represents a superior second-generation platelet concentrate that offers additional clinical benefits compared to first-generation Platelet-Rich Plasma (PRP), with proven advantages in reducing morbidity and improving patient quality of life across multiple regenerative applications. 1

Fundamental Structural and Biological Differences

Fibrin Architecture

• PRP (first-generation) exists as a liquid concentrate requiring external activation with thrombin or calcium chloride to form a gel, resulting in a rigid fibrin network that dissolves within 5 days 2, 3
• L-PRF (second-generation) forms through natural polymerization without additives, creating a flexible three-dimensional fibrin mesh that remains intact for at least 7 days, providing sustained structural support 4, 2

Cellular Composition

• PRP can be prepared with or without leukocytes, with Pure PRP (P-PRP) containing minimal white blood cells 5, 3
• L-PRF inherently contains concentrated leukocytes (neutrophils and monocytes/macrophages) that contribute to antimicrobial activity and release important chemotactic molecules 4, 5

Growth Factor Release Kinetics

• PRP releases growth factors rapidly with shorter duration, typically exhausting its biological activity within 4-5 days 2
• L-PRF demonstrates slow, sustained release of significantly larger amounts of TGF-β1, PDGF-AB, VEGF, and matrix proteins (fibronectin, vitronectin, thrombospondin-1) over 7+ days, making it superior for tissue regeneration 6, 4, 2

Clinical Outcomes and Quality of Life Impact

Proven Superiority of L-PRF

• In acne scar treatment, fluid PRF demonstrated significantly higher therapeutic response and patient satisfaction compared to PRP, both when used alone and combined with needling 6
• In recession coverage, L-PRF membranes serve as effective alternatives to connective tissue grafts with significantly reduced postoperative pain—a critical quality of life outcome often overlooked 1
• In bone regeneration, L-PRF's sustained growth factor release and structural integrity provide superior outcomes in alveolar ridge preservation, sinus augmentation, and lateral bone augmentation 1

Application-Specific Recommendations

For alveolar ridge preservation:

• Use ≥3-5 L-PRF plugs or membranes per extraction socket with firm condensation 1
• Apply double-layer L-PRF membrane coverage to seal socket entrance 1
• The number of L-PRF membranes directly correlates with clinical success 1

For sinus floor elevation:

• Use at least one L-PRF membrane per millimeter of desired bone gain 1
• L-PRF alone is only appropriate for 1-stage approaches with implants as tent poles 1

For lateral bone augmentation:

• Combine flowable PRF with bone substitute within ≤30 minutes of preparation 1
• L-PRF membranes provide sufficient graft stability with lower wound dehiscence risk compared to traditional barrier membranes 1

Critical Preparation Requirements

L-PRF Protocol (Must Follow Precisely)

• Collect blood in glass or silica-coated tubes using 21G butterfly needle 1
• Centrifuge at 408g for minimum 12 minutes (extend to 18-20 minutes for patients on anticoagulants) 1
• Never cut away the face portion (platelet- and leukocyte-rich region adjacent to red thrombus)—this is the most biologically active part and must be placed closest to the grafting site 1
• Blood collection to centrifugation must occur within ≤1 minute to ensure proper clot formation 1
• Centrifugation temperature must be ≥21°C; lower temperatures produce inconsistent, crumbly fibrin with compromised biological activity 1

PRP Limitations

• Severe lack of standardization in preparation methods, terminology, purity, and quality control across all applications 7, 8, 9
• Different preparation techniques result in significant variations in platelet yields, concentration, purity, and activation status 7, 8
• Evidence remains uncertain for most orthopedic applications including tendon injuries, bone healing, and osteoarthritis 7

Common Pitfalls to Avoid

With L-PRF:

• Slow blood collection (>1 minute) destroys the specific cellular content and matrix architecture 1
• Centrifuge vibration significantly impacts cell content—ensure stable table placement 1
• Cutting away the face portion eliminates the highest concentration of platelets and growth factors 1
• Using L-PRF clots instead of membranes yields significantly inferior clinical benefits 1

With PRP:

• Lack of product characterization (platelet concentration, yield, purity, activation status) leads to unpredictable outcomes 8
• Inconsistent preparation methods make literature comparisons unreliable 7, 9

Safety Profile

Both products are clinically safe due to their autologous nature with minimal immunogenicity risk 7, 8, 9. However, L-PRF offers the additional advantage of not requiring external activators or additives, eliminating potential contamination risks associated with thrombin or calcium chloride used in PRP preparation 4, 5.