What the Experts Require:

• PRP must contain a higher concentration of platelets than baseline, however an increase in platelets is a very gross description of PRP and does not accurately describe the variability among different types of PRP.
• There are several parameters that need to be taken into account when considering PRP, including: platelet concentration above baseline, whether or not leucocytes are included, whether or not the PRP has been anticoagulated and whether it requires exogenous activation.
• Platelet count is the first variable to consider. Absolute platelet count varies depending on the platelet concentration in the subjects’ peripheral blood. PRP devices can be usually divided into lower (2.5 – 3 times baseline concentration) and higher (5 – 9 times baseline concentration) systems.
• It would seem intuitive that a higher platelet count would yield more growth factors and better clinical results, however, this has not yet been fully determined.

The International Cellular Medicine Society (ICMS) Platelet Rich Plasma (PRP) Guidelines

What the Experts Require:

Blood contains plasma, red blood cells (RBC), white blood cells (WBC), and platelets.
Plasma is the liquid component of blood, made mostly of water and acts as a transporter for cells. Plasma also contains fibrinogen, a protein that acts like a net and catches platelets at a wound site to form a clot.
RBC helps pick up oxygen from the lungs and delivers it to other body cells, while removing carbon dioxide.
WBC fights infection, kills germs, and carries off dead blood cells.
Platelets are responsible for hemostasis, construction of new connective tissue, and revascularization.

Typically a blood specimen contains 93% RBC, 6% Platelets, and 1% WBC*. The rationale for PRP benefit lies in reversing the blood ratio by decreasing RBC to 5%, which are less useful in the healing process, and increasing platelets to 94% to stimulate recovery.

* Marx RE, Garg AK, editors. Dental and craniofacial applications of platelet rich plasma.
Quintessence Publishing Co 2005, 99:1–75.