Ultrastructure Comparison of Platelet-Rich Fibrin and Platelet-Rich Plasma

Introduction: Platelet-rich plasma (PRP) is a volume of autologous plasma which contributes large quantities of mitogenic platelet cytokines. It has been a breakthrough in the stimulation and acceleration of bone and soft tissue healing since 1998. Indeed, the potential effect of the platelet cytokines looks to be extremely limited in time. Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates geared to simplified preparation without biochemical blood handling. The fundamental advantage of PRF compared with PRP is the better fibrin network and the intrinsic relationship between the platelet and the fiber. This will prolong its action time and lead to a more efficient cell migration, roliferation and cicatrisation. At present, we couldn't find any papers reveal the its ultrastructure.

Objectives: To observe the ultrastrcuture of PRF and compare with PRP through scanning electron microscope (SEM) and transmission electron microscope (TEM), in order to find the morphological evidence to explain the concepts above.

Methods: Blood samples were taken from 6 healthy volunteers (4 males, 2 females), two samples from each person synchronously. PRP gel and PRF were prepared according to the protocols, then examined by SEM and TEM.

Results: Great differences of ultrastructure were found between PRP gel and PRF .

1. In PRP gel, no relationship was found between fibrin and platelet. Fibers were less and unsharpnessly, forming compact network. Platelet-rich areas dispersed, within which the platelets folded, extrusing massive parapodium.

2. In PRF, fibrin network was raritas and polyporus, similar to a natural clot. There is morphologic relationship between fibers and platelets. Platelets in the center of platelet crump had plenty of dark ¹ granulum inside.

Conclusions: PRF has better morphous than that of PRP. This can imply that PRF would progressively release cytokines during fibrin matrix remodeling thus it can prolong its action time.