 Intravenous blood was collected and placed into two different a 10mL glass-coated plastic tube without anticoagulant solutions. These tubes were then immediately centrifuged with a CGF centrifuge machine. The CGF clot was removed from the tube and separated from the Red Blood Cell by using microsurgical scissors. The CGF was squeezed in a special box that produces membranes at a constant thickness of 1mm.CGF membrane was immediately placed over the recession area. 