The Relevance of Choukroun’s Platelet-Rich Fibrin and Metronidazole During

Complex Maxillary Rehabilitations UsingBone Allograft. Part I: A New Grafting Protocol

Alain Simonpieri, DDS,* Marco Del Corso, DDS,† Gilberto Sammartino, MD, PhD,‡and David M. Dohan Ehrenfest, DDS, MS, PhD§

For the past several years, preim-plant surgery has made it possible,through the use of bone grafting,

to obtain a more or less total reconstitutionof the alveolar walls. This first therapeu-tic step allows the adequate positioningof the implants and the long-term suc-cess of implant-supported reconstruc-tion.1–5 However, these large-scale graftsoften require autogenous bone takenfrom the patient’s calvaria (parietal boneis very often used in France)6–8 or iliaccrest.9–11 It implies a rather significantoperation under general anesthesia, withall of the risks associated with hospital-ization and with donor site morbidity.The relative seriousness of such a pro-cedure discourages many patients anddissuades them from using these treat-ments which, however, are essential totheir facial rehabilitation, after manyyears of psychological, esthetic, andfunctional discomfort.

To simplify the graft protocols,bone substitutes have been consideredas an alternative solution to the autog-enous grafts. These substitution bio-materials can be divided into 3 overall

groups: entirely synthetic products(Cerasorb, Nanobone, etc.), xeno-grafts (lyophilized bovine bone, Bio-Oss type, etc.), and allogeneic grafts(human bone from a tissue bank). Thisallogeneic bone is generally consid-ered as an efficient and secure prod-uct.12–14 Nonetheless, its use duringlarge-scale bone grafting is relativelyundeveloped, owing to the long wait-ing period necessary for its proper in-

tegration before implants can beloaded, and to their mechanical prop-erties, which make surgical manipula-tion difficult.15 Therefore, althoughthey are frequently used for sinusgrafts,16,17 their use during significantbone grafting for alveolar ridges thick-ening remains limited.

In France, the use of Choukroun’splatelet-rich fibrin (PRF) has played asignificant role in the evolution of

*Private Practice, Monte Carlo, Monaco.†Private Practice, Department of Periodontology, TurinUniversity, Turin, Italy.‡Professor, Department of Odonto-stomatological andMaxillo-facial Sciences, University Federico II of Naples, Italy.§Researcher, Department of Biomaterials, Institute of ClinicalSciences, The Sahlgrenska Academy at University ofGothenburg, Sweden; Professor, Department of Odonto-stomatological and Maxillo-facial Sciences, University FedericoII of Naples, Italy; Researcher, the LoB5 Foundation forresearch, AP-HP, Paris, France.

ISSN 1056-6163/09/01802-102Implant DentistryVolume 18 • Number 2Copyright © 2009 by Lippincott Williams & Wilkins

DOI: 10.1097/ID.0b013e318198cf00

Extensive bone grafting remains adelicate procedure, because of theslow and difficult integration of thegrafted material into the physiologicalarchitecture. The recent use of plateletconcentrates aims to improve this pro-cess of integration by acceleratingbone and mucosal healing. Chouk-roun’s platelet-rich fibrin (PRF) is ahealing biomaterial that concentratesin a single autologous fibrin mem-brane, most platelets, leukocytes, andcytokines from a 10 mL blood harvest,without artificial biochemical modifi-cation (no anticoagulant, no bovinethrombin). Whether used as a mem-brane or as fragments, PRF allows asignificant postoperative protection ofthe surgical site and seems to acceler-ate the integration and remodeling ofthe grafted biomaterial. These proper-ties are particularly helpful for vestib-ular bone grafting on the alveolarridges. Moreover, it provides a veryhigh quality of gingival maturation.

A small quantity of a 0.5% metronida-zole solution (10 mg) can also be usedto provide an efficient protection ofthe bone graft against unavoidableanaerobic bacterial contamination.This article describes a new techniqueof total maxillary preimplant bonegrafting using allograft, Choukroun’sPRF membranes and metronidazole.This first part focused on the preim-plant reconstructive treatment usingallogeneic bone granules. PRF mem-branes are particularly helpful to pro-tect the surgical site and foster softtissue healing. This fibrin biomaterialrepresents a new opportunity to im-prove both the maturation of bonegrafts and the final esthetic result ofthe peri-implant soft tissue. (ImplantDent 2009;18:102–111)Key Words: bone graft, fibrin, freeze-dried bone allograft, platelet concen-trate, platelet-rich fibrin (PRF),platelet-rich plasma, metronidazole,sinus-lift

102 RELEVANCE OF CHOUKROUN’S PRF AND METRONIDAZOLE • SIMONPIERI ET AL

these concepts.18 This innovative bio-material can be defined as a plateletand immune concentrate19–23 that com-bines in a single fibrin membrane mosthealing- and immunity-conduciveconstituents from a 10 mL sample ofblood.

PRF was perfected in France byChoukroun et al18 in 2001. Unlikeother platelet concentrates developedthroughout the world,24–26 this tech-nique requires neither anticoagulantsnor bovine thrombin (nor any othergelifying agent). It is nothing else thancentrifuged blood without additives,conforming to all French laws relatedto the reimplantation of blood prod-ucts. This technology requires ade-quate table centrifuge and collectionkit (PC-02, Process Ltd., Nice,France).27

The protocol is very simple:whole blood is drawn in 10-mL tubeswithout anticoagulant27 and is imme-diately centrifuged at around 400 g for12 minutes (Process protocol, Nice,France). Within few minutes, the ab-sence of anticoagulant allows the ac-tivation of the majority of the plateletscontained in the sample, in contactwith the tube walls, thus triggering acoagulation cascade. The fibrinogen isat first concentrated in the upper partof the tube, until the effect of the cir-culating thrombin transforms it into afibrin network. The result is a fibrinclot located in the middle of the tubeand soaked with acellular plasma, witha maximum number of plateletscaught in the fibrin mesh.

When used as a membrane, PRFenables the protection of operativesites from outside aggression andserves as a matrix to accelerate thehealing of wound edges,28 much like afibrin bandage.22,29 When mixed withthe graft material, the fibrin clot func-tions as a biological connector be-tween the different elements of thegraft, and as a matrix which favorsneo-angiogenesis, the capture of stemcells, and the migration of osteopro-genitor cells to the center of thegraft.22,23 The addition of PRF to graftmaterial could therefore become a se-rious opportunity to develop new ther-apeutic procedures by improving theintegration of bone substitution mate-

rials during preimplant grafting.30–32

The clinical case that follows is a de-tailed illustration of this concept.

CLINICAL ILLUSTRATIONThe Initial Situation

A 52-year-old female patient con-sulted on December 4, 2002. Becauseof a series of infections and a severeperiodontal disease which was not im-mediately diagnosed, she had formany years been wearing a partialremovable dental prosthesis. The 3 re-maining teeth (17, 26, 27), secondarilyinfected, had induced a polypoid reac-tion in the mucous membrane of theright sinus. Given her young age, thisprosthesis was, for her, a source ofpermanent psychological sufferingand a symbol of the mutilation of herface. Under the prosthesis, the maxil-lary alveolar ridges had already under-gone significant centripetal resorption,both in height and— especially—inthickness. It was thus impossible toplace axial implants without a preim-plant reconstruction of the maxillaryusing bone grafts. This diagnosis wasconfirmed by the computed tomogra-phy scan examination, which clearlyshowed a subantral bone height of 3mm and anterior ridges measuring lessthan 3 mm thick (Fig. 1). It was decidedto first eliminate all remaining maxillaryand mandibular sources of infection.Then, a complete removable maxillaryprosthesis and a partial mandibular pros-thesis were temporarily used.

After being clearly and openlyinformed on the different therapeuticoptions available to her, the patientaccepted a multiphase treatment plancombining preimplant allografts andcomplete implant-supported maxillaryrehabilitation.

Graft Surgery

During the preimplant phase, itwas necessary to reconstruct resorbedmaxillary bone structures. Indeed, theremaining architecture was unsuitablefor adequate implantation. The entiresurgical site was first opened, then themedullar bone along the vestibularside of the anterior alveolar ridges wasstimulated, to facilitate proper vascu-larization and integration of the graft.

In the posterior area, the 2 sinuseswere opened to be filled (Fig. 2).

The bone graft consisted of acombination of freeze-dried bone allo-graft Phoenix (TBF, Mions, France)and of PRF. This mixture, soaked inmetronidazole (0.5% solution), wasused to fill the sinuses and to consid-erably thicken the vestibular side ofthe anterior and central alveolar ridges(Fig. 3, A). To protect the graft and toaccelerate healing of the crestal inci-sion, a large quantity of PRF mem-branes was used to cover the entiregrafted area (Fig. 3, B). Sutures shouldkeep the PRF membranes flattened un-der the flap (Fig. 3, C). Three daysafter the surgery, the sutures were re-moved. The PRF membranes acted asfibrin bandages, enabling quick clo-sure of the surgical site despite thesubstantial volume of bone added(Fig. 4). Three months after graft sur-gery and healing on a PRF fibrin bed,gingival tissue looked thick and kera-tinized. Note that the PRF membranes

Fig. 1. At the patient’s first consultation at theend of 2002, she had only 3 remaining pos-terior teeth in the maxillary (A). They weresources of infection into the sinus and hadinduced the polypoid thickening visible on thecomputed tomography scans (B). The pa-tient displayed considerable maxillary boneresorption, which had contributed to the col-lapse of the lower level of the face and to theabsence of lip support. Extraction of the in-fected teeth and cleansing of the oral cavityrevealed extremely thin maxillary alveolarridges (C).

IMPLANT DENTISTRY / VOLUME 18, NUMBER 2 2009 103

were obtained using the standard pro-tocol described in the scientific litera-ture.18,19

To avoid pressure on the graftedmaterial (it could induce mobility andfibrosis of the graft), the patient wasnot allowed to wear a temporary re-movable prosthesis for the 40 daysafter the surgery. This waiting periodis considerably shorter in the case ofautogenous onlay bone grafts fixedwith screws, because the allograft bi-omaterial is constituted of bone gran-ules and has not a rigid architecture.The initial healing time should be longenough to allow the bone graft to be-

come compact, before functionalforces are applied.

Ten weeks (75 days) after the sur-gery, a preimplant computed tomogra-phy scan was performed. There was aradiological homogeneity between thegrafted bone and the remaining alveo-lar walls (Fig. 5). The graft appearedto be integrated.

DISCUSSIONPRF and Metronidazole for Bone Grafting

Choukroun’s PRF is a matrix ofautologous fibrin, in which are embed-ded a large quantity of platelet and

leukocyte cytokines during centrifuga-tion.19–21 The intrinsic incorporation ofcytokines within the fibrin mesh im-plies their progressive release overtime, as the network of fibrin disinte-grates. At one of its extremities, eachPRF clot also concentrates most plate-lets and leukocytes collected in its 10mL tube of blood.

The use of this platelet and im-mune concentrate during bone graftingoffers the following 4 advantages:

First, the fibrin clot plays an im-portant mechanical role. Although itdoes not possess significant adhesiveproperties (unlike fibrin glues orplatelet-rich plasmas), the strength ofPRF membranes enables a biomaterialto be maintained and protected againstmoderate parasitic forces.33 Moreover,mixed with the graft, PRF fragmentsserve as a biological connector betweenbone particles. Soaked in serum, theyfavor the adhesion of allogeneic bonechips and constitute a biological cementbetween these fragments. This cohesiongives to the graft a biomechanicalstrength which is crucial during the firststeps of healing, particularly on a site asexposed as the vestibular surface of amaxillary alveolar wall.

Second, the integration of thisfibrin network with fragments of allo-geneic bone facilitates cellular migra-tion, particularly for endothelial cellsnecessary for the neo-angiogenesis,34

vascularization and survival of the graft,as well as for mesenchymal stem cells(drifting or close to wound site). Theincorporation of a fibrin network into agrafted mass of lyophilized inactivebone would thus be very positive: pathsof cellular migration would appearwithin the bundles of PRF that vein thegraft. Moreover, this fibrin bandage actsas a healing matrix35 for the soft tissuearound the incision and the wholewounded site. Indeed, we can systemat-ically observe a high gingival matura-tion after healing on PRF membranes,with a thickening of keratinized gingivaltissues which improves the esthetic in-tegration and final result of prostheticrehabilitations.33

Third, the platelet cytokines, es-sentially platelet-derived growth fac-tors, transforming growth factor �-1,and insulin-like growth factors, seem

Fig. 2. First, the entire surgical site was opened (A). The medullar bone along the vestibularside of the anterior alveolar ridges was stimulated (B). In the posterior area, the 2 sinuses wereopened to be filled (C and D).

Fig. 3. The mixture of human lyophilized bone (Phoenix freeze-dried bone allograft, TBF,France) and PRF, soaked in metronidazole, was used to fill the sinuses and to considerablythicken the vestibular side of the anterior and central alveolar ridges (A). PRF membranes wereplaced to cover the entire grafted area (B). After suturing, the PRF membranes were protectedunder the flap (C). One day after the graft surgery, healing of the incision line seemed alreadysatisfactory for the protection of the graft underneath.

104 RELEVANCE OF CHOUKROUN’S PRF AND METRONIDAZOLE • SIMONPIERI ET AL

gradually released as the fibrin matrixis resorbed, thus creating a perpetualprocess of healing.20,28 These mecha-nisms of gradual release are used bythe organism to guide healing and con-nective tissue remodelling (such asbone), but such a phenomenon is dif-ficult to reproduce synthetically. PRF,however, through physiological poly-merization, seems to have this slowrelease property. It reproduces the el-ementary mechanisms of hemostasisand healing, on the scale of a fibrinclot which is large enough to be usedclinically. In the middle of a bonegraft, particularly with lyophilizedbone, such a mid- and long-term ca-pacity to maintain healing and remod-eling would be extremely beneficialfor the maturation of the graft and itsoverall integration over time.23

Lastly, the role of PRF in immu-nity seems significant, because of thepresence in the fibrin clot of an impor-tant number of leukocytes activated bythe centrifugation, and because of the

incorporation of inflammatory andanti-inflammatory cytokines into thenetwork of fibrin.21 The gradual re-lease of these molecules would play asignificant role in the self-regulationof inflammatory and infectious phe-nomena within the grafted material.Indeed, all clinical experiences em-phasized that the use of PRF seems toreduce postoperative pain and edemas,and to limit even minor infectious phe-nomena. The control of inflammationand especially the risk of sepsis withina bone graft seems yet another deci-sive reason to use PRF during bonegrafting.

Metronidazole could be anotherdecisive surgical adjuvant. This anti-biotic from the nitro-5-imidazole fam-ily is often used orally or appliedlocally. Incorporated into the graftmaterial during bone graft surgery, itprotects against the systematic perop-erative contamination by anaerobicbacteria.36 However, metronidazolewill never replace rigorous asepticconditions during the operation, com-bined with a general antiseptic covering.This protocol is not an antibiotherapy:2 mL of this 0.5% solution are con-taining only 10 mg of metronidazole,i.e., 1/20 of a standard 200 mg oraltablet. This is just enough to limit thecontamination of the biomaterial andto protect the early phases of boneconstruction from infection and the re-lated inflammatory reaction. The localuse of this small quantity of metroni-dazole thus enables the practitioner toincrease the quality of maturation ofthe graft, and to reduce the risk of

developing bone infection and, even-tually, necrosis.

The combination, within the graft,of these 2 adjuvants seems to increasethe radiological and histological qual-ity of the grafted bone tissue.23 Theuse of PRF membranes likewise con-siderably improves the healing andmaturation of soft tissue.33 In thissense, PRF is a healing concentrate: itcontains, in a single usable membrane,most key elements of hemostasis andhealing.

CONCLUSION

The use of bone substitutes duringextensive bone grafting remains a del-icate procedure, because of the chal-lenge of adequate integration of thegraft. The use of PRF during theseinterventions offers better postopera-tive control of the surgical site andseems to accelerate the integration andremodeling of the grafted biomaterial.Combined with existing maxillofacialimplant reconstructive therapy, PRFrepresents a new opportunity to im-prove grafting procedures, keepingin mind that it is a healing biomate-rial and not a “miracle” product. Itjust increases the potential for ther-apeutic success when used by askilled practitioner.

Disclosure

The authors claim to have no fi-nancial interest, directly or indirectly,in any entity that is commercially re-lated to the products mentioned in thisarticle.

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Reprint requests and correspondence to:David M. Dohan Ehrenfest, DDS, MS, PhDDepartment of BiomaterialsInstitute for Clinical SciencesThe Sahlgrenska Academy at University ofGothenburgMedicinaregatan 8B, 41390 Gothenburg,SwedenPhone: 00 33 6 64 72 95 40E-mail: LoB5@mac.com ordrdohand@hotmail.com

106 RELEVANCE OF CHOUKROUN’S PRF AND METRONIDAZOLE • SIMONPIERI ET AL

Abstract Translations

GERMAN / DEUTSCHAUTOR(EN): Alain Simonpieri, DDS, Marco Del Corso,DDS, Gilberto Sammartino, MD, PhD, David M. DohanEhrenfest, DDS, MS, PhD. Korrespondenz an: David M.Dohan Ehrenfest, Abteilung fur Biomaterialien (Departmentof Biomaterials), Institut der klinischen Wissenschaften (In-stitute for Clinical Sciences), die Sahlgrenska Akademie derUniversitat von Goteborg (The Sahlgrenska Academy at Uni-versity of Gothenburg), Medicinaregatan 8B, 41390 Gote-borg, Schweden. Telefon.: 00 33 6 64 72 95 40, e-Mail:LoB5@mac.com bzw.drdohand@hotmail.comDie Bedeutung des Thrombozytreichen Fibrins von Chouk-roun (PRF) und Metronizadol bei komplexen Wiederher-stellungsbehandlungen im Oberkiefer unter Anwendungvon Knochenallotransplantat. Teil I: Ein neues Transplan-tierungsprotokoll. Teil I

ZUSAMMENFASSUNG:Weitreichende Knochengeweb-stransplantation bleibt nach wie vor schwierig, da das trans-plantierte Material sich nur langsam und unter Schwierigkeiten indie physiologische Gesamtarchitektur eingliedert. Die neuar-tige Verwendung von Thrombozytkonzentraten zielt daraufab, diesen Integrationsprozess durch die Beschleunigung derHeilung von Knochengewebe und Schleimhaut zu ver-bessern. Bei Choukrouns Thrombozytreichem Fibrin (PRF)handelt es sich um ein heilendes Biomaterial in einemKonzentrat einer einzelnen autologen Fibrinmembran, denmeisten Thrombozyten, Leukozyten und Zytokinen aus einer10 ml Blutprobe ohne kunstliche biochemische Veranderung.d.h. keine Antikoagulantien oder Rinderthrombin. Ob alskomplette Membran oder in Fragmenten eingesetzt, immerbietet das Thrombozytreiche Fibrin einen bedeutendenSchutz der chirurgischen Eingriffstelle nach der Operationund scheint gleichzeitig die Integration sowie den Neuaufbaudes transplantierten Biomaterials zu beschleunigen. DieseEigenschaften sind besonders bei Transplantierung von Ves-tibularknochen am Alveolarkamm von großem Vorteil.Außerdem sorgt dieses Material fur ein gutes Maß an Zahn-fleischreifung. Eine geringe Menge einer 0,5%-igen Metroni-zadollosung (10mg) kann außerdem eingesetzt werden, umdas Knochentransplantat gut gegen unvermeidbare anaerobebakterielle Verunreinigungen zu schutzen. Dieser Artikel be-schreibt eine neuartige Technik der kompletten Knochen-transplantierung im Oberkiefer vor Implantierung mittelsAllotransplantat, Membranen von Choukrouns Thrombozy-treichem Fibrin und Metronizadol. Dieser erste Teil konzentriertsich auf die rekonstruktive Behandlung vor Implantatsetzungunter Verwendung von allogenen Knochengranula. DieMembranen aus Thrombozytreichem Fibrin sind zum Schutzder chirurgischen Eingriffstelle sowie zur Beschleunigungdes Heilungsprozesses des Weichgewebes von besonderem

Vorteil. Dieses Fibrin-Biomaterial bietet damit ganz neuar-tige Optionen zur Verbesserung sowohl der Reifung derKnochentransplantate als auch des abschließenden asthetis-chen Ergebnisses des Weichgewebes im das Implantat um-lagernden Gewebe.

SCHLUSSELWORTER: Knochentransplantat, Fibrin, gefrier-getrocknetes Knochenallotransplantat (FDBA), Thrombozyt-konzentrat, Thrombozytreiches Fibrin (PRF), ThrombozytreichesPlasma (PRP), Metronizadol, Sinusanhebung

SPANISH / ESPAÑOLAUTOR(ES): Alain Simonpieri, DDS, Marco Del Corso,DDS, Gilberto Sammartino, MD, PhD, David M. DohanEhrenfest, DDS, MS, PhD. Correspondencia a: David M.Dohan Ehrenfest, Department of Biomaterials, Institute forClinical Sciences, The Sahlgrenska Academy at University ofGothenburg, Medicinaregatan 8B, 41390 Gothenburg, Swe-den. Telefono: 00 33 6 64 72 95 40, Correo electronico:LoB5@mac.com o drdohand@hotmail.comLa relevancia de la fibrina rica en plaquetas de Choukroun(PRF por sus siglas en ingles) y metronidazol duranterehabilitaciones maxilares complejas usando un aloinjertode hueso. Parte I: Un nuevo protocolo para injertos.Parte I

ABSTRACTO: Los extensos injertos de hueso siguen siendoun procedimiento delicado, debido a la integracion lenta ydificultosa del material injertado en la arquitectura fisio-logica. El uso reciente de concentrados de plaquetas trata demejorar este proceso de integracion al acelerar la curacion delhueso y la mucosa. La fibrina rica en plaquetas de Choukroun(PRF por sus siglas en ingles) es un biomaterial de curacionque concentra en una sola membrana de fibrina autologa lamayoría de las plaquetas, leucocitos y citocinas de unarecoleccion de sangre de 10 mL sin modificacion bioquímicaartificial (sin anticoagulante, sin trombina de bovinos). Yasea que se use como membrana o como fragmentos, la PRFpermite una proteccion postoperatoria significativa del lugarquirurgico y parece acelerar la integracion y remodelacion delbiomaterial injertado. Estas propiedades son particularmenteutiles para el injerto de hueso vestibular en las crestas alveo-lares. Ademas, proporciona una maduracion gingival de muyalta calidad. Tambien se puede usar una pequena cantidad desolucion de metronidazol al 0,5% (10 mg) para proporcionaruna proteccion eficaz del injerto de hueso contra la contami-nacion inevitable con bacterias anaerobicas. Este artículodescribe una nueva tecnica para el injerto de hueso maxilartotal previo al implante usando un aloinjerto, las membranasde PRF de Choukroun y metronidazol. Esta primera parte seconcentra en el tratamiento reconstructivo previo al implante

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usando granulos de hueso alogenico. Las membranas de PRFson particularmente utiles para proteger el lugar quirurgico yapoyar la curacion del tejido suave. Este biomaterial confibrina representa una nueva oportunidad para mejorar lamaduracion de los injertos de hueso y el resultado esteticofinal del tejido suave periimplante.

PALABRAS CLAVES: injerto de hueso, fibrina, aloinjertode hueso congelado-desecado (FDBA por sus siglas eningles), concentrado de plaquetas, fibrina rica en plaquetas(PRF), plasma rico en plaquetas (PRP), metronidazol, el-evacion del seno

PORTUGUESE / PORTUGUÊSAUTOR(ES): Alain Simonpieri, Cirurgiao-Dentista, MarcoDel Corso, Cirurgiao-Dentista, Gilberto Sammartino, Mestreem Odontologia, PhD, David M. Dohan Ehrenfest, Cirurgiao-Dentista, Mestre em Ciencia, PhD. Correspondencia para:David M. Dohan Ehrenfest, Department of Biomaterials,Institute for Clinical Sciences, The Sahlgrenska Academy atUniversity of Gothenburg, Medicinaregatan 8B, 41390 Goth-enburg, Sweden. Telefone: 00 33 6 64 72 95 40, e-mail:LoB5@mac.com ou drdohand@hotmail.comA relevancia da Fibrina Rica em Plaquetas (PRF) deChoukroun e metronidazol durante complexas reabilitacoesmaxilares usando enxerto aloplastico de osso. Parte I: umnovo protocolo de enxertamento. Parte I

RESUMO: O enxertamento extensivo de osso permanece umprocedimento delicado, devido a lenta e difícil integracao domaterial enxertado na arquitetura fisiologica. O uso recentede concentrados de plaquetas visa melhorar esse processo deintegracao acelerando a cura do osso e mucosal. A FibrinaRica em Plaquetas (PRF) de Choukroun e um biomaterialcurativo que concentra numa unica membrana de fibrinaautologa, sobretudo plaquetas, leucocitos e citocinas de coletade sangue de 10mL, sem modificacao bioquímica artificial(sem anticoagulante, sem trombina bovina). Se usada comomembrana ou fragmento, a PRF permite uma significativaprotecao pos-operatoria do local cirurgico e parece acelerar aintegracao e remodelacao do biomaterial enxertado. Essaspropriedades sao particularmente uteis para enxertamento deosso vestibular nos rebordos alveolares. Alem disso, propor-ciona uma qualidade muito alta de maturacao gengival. Umapequena quantidade de solucao de metronidazol a 0,5%(10mg) tambem pode ser usada para proporcionar uma pro-tecao eficiente do enxerto osseo contra inevitavel contamina-cao bacteriana anaerobica. Este artigo descreve uma novatecnica de total enxertamento de osso pre-implante maxilarusando enxerto aloplastico, membranas PRF de Choukroun emetronidazol. Esta primeira parte focalizou o tratamento re-construtivo pre-implante usando granulos de osso alogeneico.As membranas PRF sao particularmente uteis para proteger olocal cirurgico e promover a suave cura do tecido. Estebiomaterial de fibrina representa uma nova oportunidade de

melhorar tanto a maturacao de enxertos de osso quanto oresultado estetico final do tecido mole do periimplante.

PALAVRAS-CHAVE: enxerto osseo, enxerto aloplastico deosso seco por congelamento (FDBA), concentrado de plaqu-etas, Fibrina Rica em Plaquetas (PRF), Plasma Rico emPlaquetas (PRP), metronidazol, elevacao da cavidade

RUSSIAN /������: Alain Simonpieri, ������ ���������� �����������, Marco Del Corso, ������ ���������� �����������, Gilberto Sammartino, ������ ��������,������ ���������, David M. Dohan Ehrenfest, ���������������� �����������, ������ ����������������, ������ ���������. ����� ������������� : David M. Dohan Ehrenfest, Departmentof Biomaterials, Institute for Clinical Sciences, The Sahlg-renska Academy at University of Gothenburg, Medicinarega-tan 8B, 41390 Gothenburg, Sweden. ������: 00 33 6 64 7295 40, ����� ��������� ���: LoB5@mac.com � drdohand@hotmail.com������� � �������� ���� ��� �������- ��� ������ (PRF) �� �� ��� ������ ��� ��������� ��� ��������� ���������������� ���� ������ ��! � ��������� ��- ��� ���� ����� � �. "� � I: ��#� ���- ���� ����� ����. "� � I

�$%&'$. �������� ������� ���������������������� ��������� ��������� ��-�� �������� ������� ��������� ������������������ ���������� ������������� �����������. ���������� ���������� ����� �������� ������������� ��������-����� ����� ���������� ���� ������� ����� ������� ��������� ����������� ������������������� ������ � ������ �����. ����� ������������ ������ (PRF) �� ������ – !��������������� �������� �� �������� �������� ��������� ��������, ������� ���������������, �� ������� � ��������� ������� �������� ����� ��"���� 10 ��, ��� ������������ ����������� ����������� (��� ������������� ������ ��������).

#���������� ���� � ���� ��������, ���� � �������������, PRF ����������� ��������������������������� ��$��� ������� �������� �,��������, �������� ��������� � ����������������������������������� ���������. %����� ��� ������������ ������� ��� �������������������������� ����� �� ������������ �����. ��������, �� ����������� ���� ������� ������� ���-����� ������� �����. &���� ���������!���������� ��$��� ������� ������������� ��������'��� ���������� ���!������� ����������,

108 RELEVANCE OF CHOUKROUN’S PRF AND METRONIDAZOLE • SIMONPIERI ET AL

��'�� ������������ ��������� ��������� 0,5 %�������� ������������� (10 �).

� ������ ����������� ����� �������� ����� ������������������ �������������� ������ ������ � �������������� �����������������, PRF-������� �� ������ � �������������. � ����� ���� ��������������� ����������������������������������� ������� � ����������������������� ������� �����. PRF-���������������� !��������� ��� ��$��� ������� ��������� �������������� ���������� ����� ����� .%���� ��������� ����������� ��������� ����������'����� ��� ��� �������� �������� ��������������������, ��� � ��� ���������� �������!���������� ���������� � ����������������������� ����� ����� .

()&"$��$ *)���: ������ ������������, ��-����, ���������������� ������ ������������(FDBA), �������������� �����, ����� ��������-���� ������ (PRF), ������ ������������ ������(PRP), ������������, �����-������

TURKISH / TURKCEYAZARLAR: Alain Simonpieri, DDS, Marco Del Corso, DDS,Gilberto Sammartino, MD, PhD, David M. Dohan Ehrenfest,DDS, MS, PhD. Yazısma icin: David M. Dohan Ehrenfest,Department of Biomaterials, Institute for Clinical Sciences, TheSahlgrenska Academy at University of Gothenburg, Medicinar-egatan 8B, 41390 Gothenburg, Isvec. Telefon: 00 33 6 64 72 9540. E-posta : LoB5@mac.com veya drdohand@hotmail.com.Kemik allogreft kullanan kompleks maksiller rehabilitasyon-larda Choukroun’un Plateletten Zengin Fibrini (PRF) ve met-ronidazol. Bolum I: Yeni bir greftleme Protokolu. Bolum I

OZET: Buyuk olcude kemik greftleme, greft materyalininfizyolojik mimariye agır ve zor entegrasyonu nedeniyle nazikbir prosedurdur. Yakın gecmiste platelet (trombosit)konsantrelerinin kullanımı, kemik ve mukoza iyilesmesinihızlandırmak suretiyle bu entegrasyon surecini gelistirmeyiamaclamaktadır. Choukroun’un Plateletten Zengin Fibrini(PRF), yapay biyo-mekanik degisiklik olmadan (anti-koagulan veya bovin trombin olmadan) 10 mL’lik bir kanhasatından alınan cogu plateleti, lokositi ve sitokini tek birotolog fibrin membranında yogunlastıran iyilestirici bir biyo-materyaldir. Gerek membran olarak, gerekse parca olarakkullanıldıgında PRF, cerrahi yerinde anlamlı derecede post-operatif koruma saglamakta ve greftlenen biyo-materyalinentegrasyonunu ve yeniden sekillenmesini hızlandırmaktadır.Bu nitelikler, ozellikle de alveoler krette vestibular kemikgreftlemeye yardımcı olur. Ayrıca, bu sekilde yuksek kalitelidis eti olgunlasması da saglanmaktadır. Kemik greftini kacı-nılmaz anaerobik bakteri kontaminasyonuna karsı etkin birsekilde korumak icin kucuk miktarda 0.5% metronidazolsolusyonu (10 mg) da kullanılabilir. Bu calısma, allogreft,Choukroun’un PRF membranları ve metronidazol kullanıla-rak gerceklestirilen yeni bir total maksiller, implant oncesikemik greftleme yontemini sunmaktadır. Bu birinci bolum,allogenik kemik granulleri kullanan implant oncesi rekon-struktif tedaviye odaklanmaktadır. PRF membranları, cerrahiyerini korumak ve yumusak dokunun iyilesmesini tesvik et-mek acısından ozellikle yararlıdır. Bu fibrin biyo-materyali,hem kemik greftlerin olgunlasmasının ve hem de peri-implantyumusak dokunun son estetik goruntusunun gelistirilmesiacısından yeni bir fırsat sunmaktadır.

ANAHTAR KELIMELER: kemik grefti, fibrin, dondurul-mus kuru kemik allogrefti (FDBA), platelet konsantresi,Plateletten Zengin Fibrin (PRF), Plateletten Zengin Plazma(PRP), metronidazol, sinus kaldırma.

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JAPANESE /

CHINESE /

110 RELEVANCE OF CHOUKROUN’S PRF AND METRONIDAZOLE • SIMONPIERI ET AL

KOREAN /

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