Table 4.

Centrifugation protocols used in each study

Study	PRF-type	Tube	RPM (RCF [×g])	Centrifugation time (min)	Centrifuge
Castro et al. [41]	L-PRF	9­ml silica-­coated plastic tubes without anticoagulant (BVBCTP-­2, Intra-­Spin, Intra-­Lock)	2700 rpm (RCFclot: 408 g)	12	Intra-­Spin, Intra-­Lock
	A-PRF +	10-ml glass tubes without anticoagulant (DUO) for A-­PRF +	1300 rpm (RCFclot: 145 g)	8	DUO Process
Sharma et al. [54]	PRF	6 ml intravenous blood was collected in a 10-ml sterile tube without anticoagulant	3000 rpm	10	LabTech AVI-532-BL centrifugation machine
Mourao et al. [56]	L-PRF	10-ml red tubes (IntraSpin™, Biohorizons®)	2700 rpm (708×g)	12	IntraSpin™, Biohorizons®, Birmingham, Alabama, USA
Canellas et al. [47]	L-PRF	sterile, glass-coated plastic tubes	2700 (708×g)	12	Intra-Lock, Boca Raton, Florida, USA
Srinivas et al. [48]	L-PRF	10 ml test tubes which were kept without an anticoagulant	3000 rpm	10	Not reported
Ahmed et al. [53]	L-PRF	Not reported	3000 rpm	10	Not reported
Areewong et al. [55]	L-PRF	Glass tube	2700 rpm	12	IntraSpin, Intra-Lock, Nice, France
Ustaoglu et al. [42]	L-PRF	9 mL tubes	2700 rpm	12	Intra-Spin System, L-PRF kit, Intra-Lock, Boca-Raton, FL, USA
	T-PRF	Grade IV sterile titanium tubes	2800 rpm	12	Not reported
Giudice et al. [40]	A-PRF +	A-PRF + tubes	1300 rpm	8	DUO centrifuge (Process for PRF, Nice, France);
	L-PRF	Red tubes	2700 rpm	18	(Intra-Lock International, Boca Raton, Florida, USA
Zhang et al. [49]	L-PRF	test tubes without any anticoagulant	400×g	10	Hettich® Universal 320 (Andreas Hettich GmbH & Co.KG, Tuttlingen, Germany)
Kumar et al. [43]	PRF	Not reported	3000 rpm	10	Not reported
Asmael et al. [58]	PRF	Five or ten milliliters of intravenous blood was drawn in 10 mL glass vacuumed tube without anticoagulants	3000 rpm	10	Centrifuge machine (Xiangtian, Jiangsu China)
Clark et al. [39]	A-PRF	01 mL sterile glass vacuum tube	1300 rpm	8	Not reported
Alzahrani et al. [44]	PRF	Not reported	3000 (400×g)	10	Compact centrifuge (Hermle labortechnik, Germany)
Temmerman et al. [50]	L-PRF	Plastic 10-mL tubes without anticoagulant	2700 rpm	12	(IntraSpin™, IntraLock, Boca Raton, Florida, USA)
Marenzi et al. [57]	L-PRF	9-mL tubes	2700 rpm	12	Intra-Lock, Boca-Raton, FL, USA
Suttapreyasri et al. [45]	L-PRF	10-mL glass tube	3000 rpm	10	Hettich Zentrifugen centrifuge EBA 20 (Andreas Hettich GmbH& Co, KG, Tuttlingen, Germany
Hauser et al. [46]	PRF	8-mL tubes without anticoagulant	2700 rpm	8	Not reported
Thakkar et al. [52]	PRF	10 ml syringe	3000 rpm	10	Not reported
Yewale et al. [51]	A-PRF +	10-mL tubes without anticoagulants	1300 rpm (208×g)	8	Not reported