Release Kinetics in PRF Versus GEM21S With and Without Bone Substitutes: An In Vitro Analysis

  • End date
    Jun 25, 2024
  • participants needed
  • sponsor
    University of Alabama at Birmingham
Updated on 25 July 2022
bone graft
Accepts healthy volunteers


This study is seeking to evaluate that platelet-derived growth factor-BB (PDGF-BB) is a proven wound healing and osteogenic protein that plays a critical role in wound healing and previous research has demonstrated a non-linear response where higher dosages produced less effect. As Platelet Rich Fibrin (PRF) contains numerous platelets, it contains PDGF-BB, but at levels lower than in the commercially available product and with inter-individual variation, GEM21S. To achieve both ideal handling and achieve ideal levels of PDGF-BB, there is a rationale to add GEM 21S recombinant human platelet-derived growth factor-BB (rhPDGF) to a bone graft prior to making "sticky bone".


Innovations in biomedicine and recombinant protein technology show promising advances for the regeneration of advanced alveolar defects. Recombinant growth factors and biologics encourage minimally invasive procedures with improved clinical outcomes/healing times in complex oral surgery procedures. PDGF-BB is a growth factor that is known to be a potent mitogen and chemotactic agent for cells important in wound healing and bone regeneration. PDGF-BB is also a strong angiogenic agent. These properties provide a solid biological mechanism of action and rationale for the widespread use of rhPDGF-BB in dental and orthopedic surgery, as well as in the treatment of difficult soft tissue wounds. Practically, two sources of supra-physiologic levels PDGF-BB are currently available for use in dental hard and soft tissue defects: 1) Platelet concentrates (PRF/PRF); and 2) GEM 21S, which contains recombinant human PDGF-BB (rhPDGF-BB). Platelet rich plasma was first introduced to dentistry in 1998 by Robert Marx. Since then, other autologous products have evolved. Platelet rich fibrin (PRF) is one that is used daily in various clinical scenarios, including guided bone regeneration. The rationale for its use is due to the supraphysiologic concentration of growth factors (ie PDGF-BB) and cells to enhance would healing. Clinicians also frequently incorporate PRF to bone grating materials to improve handling properties of the graft material, also referred to as "sticky bone". However, the literature varies greatly on the believed mechanism of action and the therapeutic benefits claimed by their supporters. The rationale for this proposed study that PDGF-BB is a proven wound healing and osteogenic protein, but there are clinically insignificant amounts of PDGF-BB in PRF. Therefore, there is a rationale to add GEM 21S (rhPDGF) to a bone graft prior to making "sticky bone" with PRF. This would provide clinicians the benefits of a clinically proven and consistent dose of rhPDGF to improve wound healing and bone formation in conjunction with the benefits of the improved handling (i.e. sticky bone) from the addition of the PRF.

Condition Bone Loss
Treatment Amount of PDGF-BB in PRF preparation vs. GEM21, Amount of PDGF-BB available in PRF + bone substitutes vs. rhPDGF-BB+ bone substitutes following preparation, Release kinetics of PDGF-BB in PRF + bone substitutes vs. rhPDGF-BB + bone substitutes, Release kinetics of PDGF-BB in rhPDGF-BB + PRF + bone substitutes
Clinical Study IdentifierNCT04964466
SponsorUniversity of Alabama at Birmingham
Last Modified on25 July 2022


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Inclusion Criteria

English speaking
At least 18 years old
Able to read and understand informed consent document
Systemically healthy, non-smoker, no medications

Exclusion Criteria

Non-English speaking
Less than 18 years old
Smokers/tobacco users (>10 cigarettes/day)
Patients with systemic pathologies or conditions contraindicating oral surgical procedures or adversely affecting healing
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