Preparation of CGF
’ fresh venous blood, tooth
STERILE, CAVITY
CGF was prepared 15 min before tooth extraction. Patients’ fresh venous blood (20 ml) was collected and placed in 2 sterile test tubes without anticoagulant. One tube was prepared for extraction cavity filling, and the other was utilized to prepare CGF membrane. The test tubes were placed in the centrifuge according to the following procedures: 30 s acceleration, 2 min×2700 rpm, 4 min×2,400 rpm, 4 min × 2,700 rpm, 3 min×3,000 rpm, 36 s deceleration, stop [