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For citation purposes: Lauritano D, Avantaggiato A, Candotto V, Zollino I, Carinci F. Is platelet-rich fibrin really useful in oral and maxillofacial surgery? Lights and shadows of this new technique. Annals of Oral & Maxillofacial Surgery 2013 Sep 01;1(3):25. Co

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Is platelet-rich fibrin really useful in oral and maxillofacial surgery? Lights and shadows of this new technique

D Lauritano1*, A Avantaggiato2, V Candotto2, I Zollino2, F Carinci2

ConclusionThe platelet-rich plasmas failed to demonstrate significant benefits that justify the daily use, and the use of platelet-rich fibrin is limited to some very specific applications in which satisfactory results were achieved. Only a new simple, inexpensive and efficient technique such as the leu-cocyte- and platelet-rich fibrin will continue to develop in oral and max-illofacial surgery in the next years.

IntroductionPlatelet concentrate fibrin is an evo-lution of the fibrin glue widely used in the oral surgery. The principle of this new technology is based on concentrating platelets and growth factors in a plasma solution, and activating them in a fibrin gel in order to improve the healing of sur-gical wounds. This platelet suspen-sion, defined as platelet-rich plasma (PRP), as the platelet concentrate used in transfusional medicine, is the precursor of another autolo-gous derivated, the platelet-rich fibrin (PRF), a solid fibrin-based biomaterial. There are many diffe-rent techniques to get the platelets concentrations, but its applications have caused some confusion, as each different method led to different products with different biological potentials and applications.

A recent classification of the dif-ferent platelet concentrates divided them into four different categories depending on the leukocytes and fibrin content: pure platelet-rich plasma (P-PRP), such as cell sepa-rator PRP, Vivostat PRF or Anitua’s PRGF; leucocyte- and platelet-rich plasma (L-PRP), such as Curasan, Regen, Plateltex, SmartPReP, PCCS,

Magellan or GPS PRP; pure plaletet-rich fibrin (P-PRF), such as Fibrinet and leucocyte- and platelet-rich fibrin (L-PRF), such as Choukroun’s PRF. This classification allows us to analyse the successes and fail-ures that have occurred so far in oral surgery, and direct research towards further applications of these technologies1–3.

The different applications of the PRF were tested in various fields of surgery and particularly in periodon-tics, oral and maxillofacial surgery, ear–nose–throat plastic surgery.

In fact, these preparations are not limited to the concentration of growth factors, but associate many factors of healing such as leukocytes, fibrin matrix, circulating progenitor cells and are as complex as blood itself.

If platelets concentrates have been used to improve healing of surgical wounds (such as fibrin glue enriched with growth factors), further deve-lopments of these preparations include applications in regenerative medicine and tissue engineering. Obviously the future of these pro-ducts is related with the scientific consistency of their applications4–8. The aim of this review was to discuss PRF in oral and maxillofacial surgery.

DiscussionPRF applications in periodontologyThe topical use of platelet concen-trates is recent, and its efficiency remains controversial in periodon-tology for treatment of gingival recession. A 6-month randomised controlled clinical study has com-pared the results achieved by the use of a PRF membrane or connective

AbstractIntroductionThe healing of hard and soft tissues is mediated by a wide range of intra and extra-cellular events that are regu-lated by protein signals. It is known that platelets are involved in the pro-cess of wound healing through blood clot formation and release of growth factors that promote and maintain the wound healing.

Platelet-rich fibrin is a second generation of platelet concentrates which allows fibrin membranes to get enriched with platelets and growth factors, starting from an anticoagu-lant free blood harvest. Platelet-rich fibrin is similar to a fibrin network that allows cell migration and pro-liferation and consequently a more efficient cicatrisation.

Many growth factors such as platelet-derived growth factor and transforming growth factor are released from platelet-rich fibrin. Recent studies have demonstrated that platelet-rich fibrin has a very significant slow sustained release of key growth factors, which means that platelet-rich fibrin could stimu-late the surrounding environment to a more rapid wound healing. This review aims to analyse the clinical results of platelet-rich fibrin in peri-odontology, oral surgery and head plastic surgery.

*Corresponding authorEmail: dorina.lauritano@unimib.it1  Department of Interdisciplinary Surgery and

Medicine, University Milano Bicocca, Milan, Italy

2  Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy

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For citation purposes: Lauritano D, Avantaggiato A, Candotto V, Zollino I, Carinci F. Is platelet-rich fibrin really useful in oral and maxillofacial surgery? Lights and shadows of this new technique. Annals of Oral & Maxillofacial Surgery 2013 Sep 01;1(3):25.

tissue graft (CTG) in the treatment of gingival recession and evaluated the clinical impact of PRF on early wound healing and subjective patient dis-comfort. No difference could be found between PRF and CTG procedures in gingival recession therapy, except for a greater gain in keratinised tissue width obtained in the CTG group and enhanced wound healing associated with the PRF group9.

The same result was reached in another study, that did not dem-onstrate any clinical advantage of the use of PRF compared to enamel matrix derivative in the coverage of gingival recession with the coro-nally advanced flap procedure, but the enamel matrix derivative group showed a higher success rate in increasing wide keratinised tissue with respect to the PRF one10.

The addition of an autologous PRF clot to a modified coronally advanced flap (MCAF) (predictable treatment for multiple adjacent Miller Class I or II recession-type defects), would improve the clinical outcome com-pared to an MCAF alone for the treat-ment of multiple gingival recessions. In fact the addition of a PRF mem-brane positioned under the MCAF inferior root coverage, has shown an additional gain in gingival/mucosal thickness at 6 months compared to conventional therapy11.

PRF may be considered as the second generation of platelet con-centrates widely used in surgery to facilitate wound healing. Another study evaluated the effectiveness of PRF and PRP in the treatment of peri-odontal intrabony defects in chronic periodontitis. The results showed similar pocket depth (PD) reduc-tion, clinical attachment level (CAL) gain, and bone filling at sites treated with PRF or PRP compared with con-ventional open-flap debridement. Because PRF is less time consuming and less technique sensitive, it may seem a better treatment option than PRP12.

Other studies investigated the clinical and radiological effective-ness of autologous PRF in the treat-ment of intrabony defects of chronic periodontitis patients, and the results showed there was greater reduction in PD, more CAL gain and greater intrabony defect filling at sites treated with PRF than the open flap debridement alone13–15.

The association between PRF and bovine porous bone mineral pro-motes bone regeneration in peri-odontal defects, thereby reducing PD, improving CALs and promoting defect filling16.

PRF and oral surgeryThe regenerative medicine tech-niques are applied in dentistry to restore the bone loss: the PRF was tested for the first time in France by Dr. Choukroun17. In Choukroun’s PRF protocol, blood is collected without any anticoagulant (Figure 1) and immediately centrifuged (Figures 2 and 3). A natural coagulation pro-cess then occurs and allows for the easy collection of a L-PRF clot, with-out the need for any biochemical modification of the blood, that is, no anticoagulants, thrombin or calcium

Figure 1: Centrifuge.

Figure 2: Kit for blood sampling.

Figure 3: Blood separation after centrifugation.

Figure 4: PRF as it appears after centrifugation.

chloride are required (Figures 4 and 5). This open-access technique is the most simple and also the least expensive protocol developed so far. However, some confusion is likely

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For citation purposes: Lauritano D, Avantaggiato A, Candotto V, Zollino I, Carinci F. Is platelet-rich fibrin really useful in oral and maxillofacial surgery? Lights and shadows of this new technique. Annals of Oral & Maxillofacial Surgery 2013 Sep 01;1(3):25.

because different suppliers use simi-lar nomenclature for their distinct products (such as Vivostat PRF and Fibrinet Platelet-Rich Fibrin Matrix)18.

Bone regenerative techniques include sinus lift for implant place-ment, which is considered one of the most predictable procedures for augmenting bone maxilla. Several approaches have been developed and are currently used to assess the relevance of simultaneous sinus lift and implantation with L-PRF (Choukroun’s technique) as sole subsinus filling material. The use of L-PRF as sole filling material during simultaneous sinus lift and implan-tation seems to be a reliable surgi-cal option promoting natural bone regeneration19–23.

Early reviews of the osteotome-mediated sinus floor elevation(PRF) technique for localised sinus floor elevation and implant placement, have demonstrated a high degree of safety and success at sites with 5- to 8-mm residual subantral bone height24.

PRF-based membranes have been used for covering the alveolar ridge augmentation side in several in vivo studies. A study has compared the use of PRF with the commonly used collagen membrane Bio-Gide as scaffolds for periosteal tissue engi-neering. PRF appears to be superior to collagen (Bio-Gide) as a scaffold for human periosteal cell proli-feration. PRF membranes are also

demonstrated to be suitable for in vitro cultivation of periosteal cells for bone tissue engineering25.

The implant success is reached if implant is placed in an ideal ana-tomical position to facilitate a func-tional and aesthetic rehabilitation. However, this is not always possible, and in some cases techniques of alve-olar bone augmentation are required to compensate for bone tissue loss. These interventions sometimes require complex surgery and the use of graft material derived from animal sources. L-PRF is a new platelet con-centrate used with great success in a number of surgical procedures to optimise the wounds healing. Several studies demonstrated LPRF has the property of new bone formation26–28. Advantages of PRF alone include less surgical time, elimination of tech-niques and potential healing difficul-ties associated with membranes, and less resorption during healing, as compared to guided bone regenera-tion procedures28,29.

Another study analysed from a clinical and histological point of view, the potential use of PRF with the piezosurgery associated with deprotenised bovine bone (Bio-oss) as graft material in the augmenta-tion of the maxillary sinus in case of severe bone atrophy comparing with a control group in which only Bio-oss was used. The use of PRF reduced healing times by promoting optimum bone regeneration. At 106 days was observed a good primary stability of endoosseus implants30.

PRF for facial plastic surgeryIt’s known that platelets play a role in homeostasis, but in recent years has been studied as they improve wound healing. It was demonstrated that platelet concentrates acceler-ate wound healing. The use of a new preparation, platelet- rich fibrin matrix (PRFM) for plastic surgery of the face, such as volume augmenta-tion, fat transfer supplementation,

represent a new technique in aes-thetic surgery31. In fact injection of PRFM into the deep dermis and sub-dermis of the skin stimulates a num-ber of cellular changes that can be harnessed for use32,33.

Although platelet concentrates have enjoyed some success in plas-tic surgery a few years ago, interest has been gradually disappearing, because of the cost, the amount of blood, equipment, space, staff and the lack of evidence of benefit. A new simple method of preparing an auto-logous platelet derivative (Selphyl; Aesthetic Factors, Princeton, NJ) allows a rapid and inexpensive PRFM that can be used to improve healing after aesthetic facial interventions as well as to rejuvenate the face with-out tissue manipulation. The PRF produces an autologous and natural platelet concentrate that releases growth factors and stimulates the regeneration of the surrounding tis-sues for cosmetic applications31–34.

A randomised clinical trial has studied the effect of topical PRF on epithelialisation of donor sites and meshed split-thickness skin auto-grafts. The results have concluded that epithelialisation of donor wounds or the interstices of auto-grafts was not significantly influ-enced by PRF treatment35.

Fat grafts have always been induced neoangiogenesis. A study was designed to compare the efficacy of first- and second-generation PRPs combined with a fat graft during facial lipostructure surgery. The first comparative study highlights the effi-cacy of the platelets concentrates for adipocyte grafts. The results suggest that the combination of fat grafts and PRF is more effective than the combi-nation of fat and PRP for facial lipos-tructure surgery36.

ConclusionThe use of PRF allowed the recon-struction of the alveolar ridges at the gingival and bone levels. The PRF

Figure 5: PRF ready for surgical applications.

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For citation purposes: Lauritano D, Avantaggiato A, Candotto V, Zollino I, Carinci F. Is platelet-rich fibrin really useful in oral and maxillofacial surgery? Lights and shadows of this new technique. Annals of Oral & Maxillofacial Surgery 2013 Sep 01;1(3):25.

makes it possible to overcome some technical limitations of an implant-supported oral rehabilitation. As a general conclusion it can be said that we live in a period of transition in the use of PRP and PRF in oral and maxil-lofacial surgery.

The PRPs failed to demonstrate significant benefits that justify the daily use, and the use of PRF is limi-ted to some very specific applications in which satisfactory results were achieved. Only a new simple, inex-pensive and efficient technique such as the L-PRF will continue to develop in oral and maxillofacial surgery in the next years.

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