Literatura – L-PRF

REGENERATIVE MEDICINE

1 – The PACT (Platelet & Advanced Cell Therapies) Forum: fostering translational research, transdisciplinarity and international collaboration in tissue engineering and regenerative medicine.

Gilberto Sammartino, Marco Del Corso, Lidia M. Wisniewska, Tomasz Bielecki, Isabel Andia, Nelson R. Pinto, Chang-Qing Zhang, De-Rong Zou, and David M. Dohan Ehrenfest.

POSEIDO, Volume 2, Issue 2, June 2014, Pages 105-115

ABSTRACT

The PACT (Platelet & Advanced Cell therapies) Forum Civitatis of the POSEIDO was created to offer a multidisciplinary platform of research, publication, debates and eventually consensus for researchers in the fields of Tissue Engineering and Regenerative Medicine (TERM). In this review, the issues, endeavors and perspectives of this considerable research field are discussed and illustrated, particularly (but not only) through the example of the history, failures and success of probably the oldest method developed in regenerative medicine, the topical use of autologous platelet concentrates (commonly known as Platelet- Rich Plasma – PRP or Platelet-Rich Fibrin – PRF). The History of this domain illustrates very well that the greatest enemy of knowledge is not ignorance; it is the illusion of knowledge. Fighting against illusions in Sciences is a very complex and tricky task, requiring continuing efforts and time. This PACT for a transdisciplinary, translational and international approach in regenerative medicine is an important step in this endeavor.

Keywords: Blood platelet, fibrin, growth factors, regenerative medicine, tissue engineering.

2 – Analysis of the Leukocytes in peripheral blood and Leukocyte- and Platelet-Rich Plasma (L-PRP) in rats: A flow cytometry study.

Agata Cieslik-Bielecka, Piotr Paczek, Lukasz Sedek, Aleksandra Szantyr, Rafal Skoronski, Hom-Lay Wang, and David M. Dohan Ehrenfest.

POSEIDO, Volume 2, Issue 2, June 2014, Pages 117-27.

ABSTRACT

Background and objectives: Platelet concentrates for surgical use were often tested as surgical adjuvants in the literature, as a source of platelet growth factors to stimulate healing. Many products are often regrouped under the generic and inaccurate term of Platelet-Rich Plasma (PRP). However, what is tested in many studies is usually a combination of platelets and leukocytes (accurately termed Leukocyte- and Platelet-Rich Plasma – L-PRP). The quantity and impact of leukocytes in these preparations were not yet accurately investigated. In this article, the characteristics of white blood cells in a L-PRP obtained from rats were investigated, in order to point out the main actors and some of the mechanisms that may influence the properties of the platelet concentrates.

Materials and Methods: Blood and platelet concentrate samples were obtained from 64 healthy Wistar rats and leukocyte phenotypes were identified using flow cytometry after labeling leukocytes for CD3, CD4, CD8, CD11bc, CD18, CD25, CD27, CD28, CD45R, CD45RA, CD80, CD90, CD106 (VCAM-1), CD161a and TCRab, TCRgd, RT1B with fluorochrome- conjugated antibodies.

Results: The results have shown that the tested L-PRP contained substantial amounts of leukocytes of many different kinds, particularly T lymphocytes, B lymphocytes, NK cells, monocytes, granulocytes and eosinophils.

Discussion and Conclusion: To highlight the various ways in which these cells can influence their environment will help to better understand the complex interactions of the PRPs with the tissues. This identification of the exact cell content and the understanding of this complex cell equation are important steps towards using these blood concentrates in the best possible way, as a reliable therapeutic option to promote better healing, particularly in infected surgical or wound sites.

Keywords: Blood platelets, infection, leukocytes, platelet-rich plasma, wound healing.

3 – The impact of the centrifuge characteristics and centrifugation protocols on the cells, growth factors and fibrin architecture of a Leukocyte- and Platelet-Rich Fibrin (L-PRF) clot and membrane. Part 1: evaluation of the vibration shocks of 4 models of table centrifuges for L-PRF.

David M. Dohan Ehrenfest, Byung-Soo Kang, Marco Del Corso, Mauricio Nally, Marc Quirynen, Hom-Lay Wang, and Nelson R. Pinto.

POSEIDO, Volume 2, Issue 2, June 2014, Pages 129-39.

ABSTRACT

Background and Objectives: Platelet concentrates for surgical use (Platelet-Rich Plasma PRP or Platelet-rich fibrin PRF) are surgical adjuvants to improve healing and promote tissue regeneration. L-PRF (Leukocyte- and Platelet-Rich Fibrin) is one of the 4 families of platelet concentrates for surgical use and is widely used in oral and maxillofacial regenerative therapies. The objective of this first article was to evaluate the mechanical vibrations appearing during centrifugation in 4 models of commercially available table centrifuges frequently used to produce L-PRF.

Materials and Methods: The 4 different tested centrifuges were the original L-PRF centrifuge (Intra-Spin, Intra-Lock, the only CE and FDA cleared system for the preparation of L-PRF) and 3 other laboratory centrifuges (not CE nor FDA cleared for L-PRF): A-PRF 12 (Advanced PRF, Process), LW – UPD8 (LW Scientific) and Salvin 1310 (Salvin Dental). Each centrifuge was opened for inspection, two accelerometers were installed (one radial, one vertical), and data were collected with a spectrum analyzer. Each centrifuge was tested in 2 configurations (full-load or half load with 9ml blood collection tubes filled with water) and at the following rotational speeds: 1500, 1800, 2100, 2400, 2700, 3000 and 3300 rpm. Extra rotational speeds were used on some centrifuges. One centrifuge (Salvin) had only one available rotational speed (3400 rpm). For each test, the software documented both radial and vertical vibration.

Results: Very significant differences in the level of vibrations at each rotational speed were observed between the 4 tested machines. The original L-PRF centrifuge (Intra-Spin) was by far the most stable machine in all configurations. At the classical speed of production of L- PRF, the level of undesirable vibration on this centrifuge is between 4.5 and 6 times lower than with other centrifuges. Moreover, Intra-Spin always remains under the threshold of resonance, unlike the 3 other tested machines.

Discussion and Conclusion: Each centrifuge has its clear own profile of vibrations depending on the rotational speed, and this may impact significantly the characteristics of the PRP or PRF produced with these devices. This result may reveal a considerable flaw in all the PRP/PRF literature, as this parameter was never considered. It is now necessary to evaluate the impact of the vibration parameter on the architecture and cell content of the L- PRF clots produced with these 4 different machines.

Keywords: Blood platelets, growth factors, leukocytes, platelet-rich plasma, regenerative medicine, wound healing

4 – The impact of the centrifuge characteristics and centrifugation protocols on the cells, growth factors and fibrin architecture of a Leukocyte- and Platelet-Rich Fibrin (L-PRF) clot and membrane. Part 2: macroscopic, photonic microscopy and Scanning Electron Microscopy analysis of 4 kinds of L-PRF clots and membranes.

Nelson R. Pinto, Andrea Pereda, Paula Jiménez, Marco Del Corso, Byung-Soo Kang, Hom-Lay Wang, Marc Quirynen, and David M. Dohan Ehrenfest.

POSEIDO, Volume 2, Issue 2, June 2014, Pages 141-54

ABSTRACT

Background and Objectives: Platelet concentrates for surgical use (Platelet-Rich Plasma PRP or Platelet-rich fibrin PRF) are surgical adjuvants to improve healing and promote tissue regeneration. L-PRF (Leukocyte- and Platelet-Rich Fibrin) is one of the 4 families of platelet concentrates for surgical use and is widely used in oral and maxillofacial regenerative therapies. The objective of this second article was to evaluate the impact of the centrifuge characteristics (vibration intensity) on the cell and fibrin architecture of a L-PRF clot and membrane.

Materials and Methods: Four different commercially available centrifuges were used to produce L-PRF, following the original L-PRF production method widely described in the literature (glass-coated plastic tubes, 400g force, 12 minutes). The tested systems were the original L-PRF centrifuge (Intra-Spin, Intra-Lock, the only CE and FDA cleared system for the preparation of L-PRF) and 3 other laboratory centrifuges (not CE/FDA cleared for L- PRF): A-PRF 12 (Advanced PRF, Process), LW – UPD8 (LW Scientific) and Salvin 1310 (Salvin Dental). All clots and membranes were collected into a sterile adequate surgical box (Xpressionkit). The exact macroscopic (weights, sizes) and microscopic (photonic and scanning electron microscopy SEM) characteristics and the cell composition of the L-PRF clots and membranes produced with these 4 different machines with 4 different vibration intensity levels were evaluated.

Results: Intra-Spin showed the lowest temperature of the tubes. A-PRF and Salvin were both associated with a significant increase of temperature in the tube. Intra-Spin produced by far the heaviest clot and quantity of exudate among the 4 techniques. For clot and membrane length and width, Intra-Spin and Salvin presented similar sizes. A-PRF and LW produced much lighter, shorter and narrower clots and membranes than the 2 other centrifuges. Light microscopy analysis showed relatively similar features for all L-PRF types (concentration of cell bodies in the first half of the fibrin mesh). However, SEM illustrated considerable differences between samples. The original Intra-Spin L-PRF showed a strongly polymerized thick fibrin matrix and all cells appeared alive with a normal shape, including the textured surface aspect of activated lymphocytes. The A-PRF, Salvin and LW PRF-like membranes presented a lightly polymerized slim fibrin gel and all the visible cell bodies appeared destroyed (squashed or shrunk).

Discussion and Conclusion: This study illustrated that the centrifuge characteristics (particularly the vibrations) are directly impacting the architecture and cell content of a L- PRF clot. The original L-PRF clot (Intra-Spin) used and validated since years presented very specific characteristics, which appeared distorted when using centrifuges with a higher vibration level. A-PRF, LW and Salvin centrifuges produced PRF-like materials with a damaged and almost destroyed cell population through the standard 400g protocol developed initially for the L-PRF, and it is therefore impossible to classify these products in the L-PRF family. A-PRF, LW and Salvin centrifuges are not suitable for the production of original L-PRF clots and membranes at 400g. Further research would be interesting to evaluate how modifications of the protocol alone (for example reduction of the g forces) may influence the biological signature of the L-PRF clots and membranes, independently from the characteristics of the centrifuge.

Keywords: Blood platelets, growth factors, leukocytes, platelet-rich plasma, regenerative medicine, wound healing

5 – The impact of the centrifuge characteristics and centrifugation protocols on the cells, growth factors and fibrin architecture of a Leukocyte- and Platelet-Rich Fibrin (L-PRF) clot and membrane. Part 3: comparison of the growth factors content and slow release between the original L-PRF and the modified A-PRF (Advanced Platelet-Rich Fibrin) membranes.

David M. Dohan Ehrenfest, Marco Del Corso, Byung-Soo Kang, Nicole Lanata, Marc Quirynen, Hom-Lay Wang, and Nelson R. Pinto.

POSEIDO, Volume 2, Issue 2, June 2014, Pages 155-66

ABSTRACT

Background and Objectives: L-PRF (Leukocyte- and Platelet-Rich Fibrin) is one of the 4 families of platelet concentrates for surgical use and is widely used in oral and maxillofacial regenerative therapies. The objective of this third article was to evaluate how the changes of the L-PRF protocol may influence its biological signature, independently from the characteristics of the centrifuge.

6 – Immediate implantation and peri-implant Natural Bone Regeneration (NBR) in the severely resorbed posterior mandible using Leukocyte- and Platelet-Rich Fibrin (L-PRF): a 4-year follow-up

Marco Del Corso and David M. Dohan Ehrenfest

POSEIDO. 2013;1(2):109-16 Natural Bone Regeneration (NBR) with L-PRF

ABSTRACT

In the severely resorbed posterior mandible, the placement of dental implants in ideal position is often compromised by the significant post-extraction centrifuge alveolar bone resorption. The shape of the residual alveolar ridges and the residual bone height above the inferior alveolar nerve often make the area not suitable for direct implantation. Even if the use of short implants offers excellent results when the residual bone volumes are high and wide enough to receive these implants [1], there is no other solution than bone regeneration surgery prior to implant placement when the alveolar ridges are very thin [2]. However bone regeneration itself remains a challenge in this area, as the mandibular posterior residual alveolar ridges are always very cortical with a low vascularization and therefore not really adapted to the integration of bone grafting material or regeneration of bone cavities. Finally, the posterior mandible is a place of significant mechanical constraints applied on the bone and gingival tissues during the mastication function, and this can compromise the healing of a bone regeneration chamber, particularly through the risk of soft tissue dehiscence after the regeneration surgery.

7 – Classification of platelet concentrates: from pure platelet-rich plasma (P-PRP) to leucocyte- and platelet-rich fibrin (L-PRF)

David M. Dohan Ehrenfest, Lars Rasmusson and Tomas Albrektsson Department of Biomaterials, Institute of Clinical Sciences, The Sahlgrenska Academy at University of Gothenburg, Sweden

Trends in Biotechnology Vol.27 No.3

ABSTRACT

The topical use of platelet concentrates is recent and its efficiency remains controversial. Several techniques for platelet concentrates are available; however, their applications have been confusing because each method leads to a different product with different biology and potential uses. Here, we present classification of the different platelet concentrates into four categories, depending on their leucocyte and fibrin content: pure platelet-rich plasma (P-PRP), such as cell separator 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 leucocyteand platelet-rich fibrin (L-PRF), such as Choukroun’s PRF. This classification should help to elucidate successes and failures that have occurred so far, as well as providing an objective approach for the further development of these techniques.

8 – Platelet-rich fibrin membranes as scaffolds for periosteal tissue engineering Volker Gassling Timothy Douglas Patrick H. Warnke Yahya Ac¸il Jo¨rg Wiltfang Stephan T. Becker

Date: Accepted 4 November 2009. Clin. Oral Impl. Res. 21, 2010; 543–549. doi: 10.1111/j.1600-0501.2009.01900.x

Keywords: collagen membrane, periosteum, platelet-rich fibrin membrane, stem cell, tissue engineering

ABSTRACT

Objectives: Platelet-rich fibrin (PRF)-based membranes have been used for covering alveolar ridge augmentation side in several in vivo studies. Few in vitro studies on PRF and no studies using human periosteal cells for tissue engineering have been published. The aim is a comparison of PRF with the commonly used collagen membrane Bio-Gides as scaffolds for periosteal tissue engineering.

Material and methods: Human periosteal cells were seeded on membrane pieces (collagen [Bio-Gides] and PRF) at a density of 104 cells/well. Cell vitality was assessed by fluorescein diacetate (FDA) and propidium iodide (PI) staining, biocompatibility with the lactate dehydrogenase (LDH) test and proliferation level with the MTT, WST and BrdU tests and scanning electron microscopy (SEM).

Results: PRF membranes showed slightly inferior biocompatibility, as shown by the LDH test. The metabolic activity measured by the MTT and WST tests was higher for PRF than for collagen (BioGides). The proliferation level as measured by the BrdU test (quantitative) and SEM examinations (qualitative) revealed higher values for PRF.

Conclusion: PRF appears to be superior to collagen (Bio-Gides) as a scaffold for human periosteal cell proliferation. PRF membranes are suitable for in vitro cultivation of periosteal cells for bone tissue engineering.

9 – The concept of Screw-Guided Bone Regeneration (S-GBR). Part 3: Fast Screw-Guided Bone Regeneration (FS-GBR) in the severely resorbed preimplant posterior mandible using allograft and Leukocyte- and Platelet-Rich Fibrin (L-PRF): a 4-year follow-up

Roland Toeroek and David M. Dohan Ehrenfest

POSEIDO. 2013;1(2) Screw-¬-Guided Bone Regeneration (S-¬-GBR). Part 3 93

ABSTRACT

The rehabilitation of the severely resorbed posterior mandible remains a challenge. Even if many techniques of bone regeneration were tested with success in this area, they remain difficult surgeries and no consensus or standard have been raised yet. Because of the thick cortical bone of the mandible body, the alveolar bone regeneration or integration of a grafting material is often compromised. Moreover, the management of a regenerative compartment in this area is always difficult due to mechanical constraints and risk of soft tissue dehiscence.

In this series of article, we developed and illustrated the concept of Screw-Guided Bone Regeneration (S-GBR), with excellent results in the posterior mandible. In this form of GBR, the barrier between the bone and gingival compartment is supported and protected through the presence of screws, serving both as tent pegs to maintain the regenerative chamber space and as bone growth pillars.

Many combinations of bone materials and membranes are possible to get adequate results with various healing times, but the use of Leukocyte- and Platelet-Rich Fibrin (L-PRF) membranes as interposition, healing and maturation material became a common standard for us. L-PRF (Intra-Spin system and Xpression kit, Intra-Lock, Boca-Raton, FL, USA) is an optimized blood clot or membrane, which concentrates most of the platelets and half of the leukocytes of a blood sample.

Through the release of growth factors and the effect of fibrin, this material promotes – among other effects – quick soft tissue healing and maturation and is considered as a form of barrier for Guided Bone Regeneration. In this article, we describe a modification of the S-GBR protocol termed Fast Screw- Guided Bone Regeneration (FS-GBR), where the severely resorbed posterior mandible was treated mostly with screws, allograft material and L-PRF membranes in order to reduce significantly the healing and regeneration times of the alveolar ridges.

10 – Simultaneous Sinus-Lift and Implantation Using Microthreaded Implants and Leukocyte- and Platelet-Rich Fibrin as Sole Grafting Material: A Six-Year Experience

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

Implant Dentistry / February 2011 – Volume 20 – Issue 1 – pp 2-12 doi: 10.1097/ID.0b013e3181faa8af Clinical Science and Techniques

ABSTRACT

Purpose: Purpose: To assess the relevance of simultaneous sinus-lift and implantation with leukocyte- and platelet-rich fibrin (L-PRF, Choukroun’s technique) as sole subsinus filling material.

Materials: Twenty-three lateral sinus elevations (SA4 sinus) were performed on 20 patients with simultaneous implant placement. Seven patients were treated with 19 Astra implants (AstraTech, Mölndal, Sweden) and 13 patients with 33 Intra-Lock implants (Intra-Lock Ossean, Boca Raton, FL). L-PRF membranes were used to cover the Schneiderian membrane, the implant tips served as “tent pegs” for the L-PRF-patched sinus membranes, and the subsinus cavity was finally filled with L-PRF clots. Clinical and radiographic follow-up was performed just after implant placement, after 6 months, 1 year and each following year.

Results: Six months after surgery, all implants were clinically stable during abutment tightening. The maximum follow-up was 6 years, and all patients were followed up for a minimum of 2 years. No implant was lost during this 6-year experience, and the vertical bone gain was always substantial, between 8.5 and 12 mm bone gain (10.4 ± 1.2). The final level of the new sinus floor was always in continuation with the implant apical end, and the periimplant crestal bone height was stable.

Conclusion: The use of L-PRF as sole filling material during simultaneous sinus-lift and implantation seems to be a reliable surgical option promoting natural bone regeneration.

11- The Use of Leukocyte – and Platelet-Rich Fibrin During Immediate Postextractive Implantation and Loading for the Esthetic Replacement of a Fractured Maxillary Central Incisor

Del Corso M, Mazor Z, Rutkowski J L, Dohan Ehrenfest D M.

J Oral Implantol 2012; 2012 Apr; 38(2):181-187. PubMed PMID: 22568469.

ABSTRACT

Synopsis: An implant-supported restoration of the maxillary anterior segment that is biologically, functionally, and esthetically acceptable following traumatic injuries in the maxillary anterior segment is always complex. Healing of the tissues is always difficult to control and the development of new techniques and materials to improve these treatments is still necessary.

The use of platelet concentrates is an interesting approach. The objective of this technique is to gather platelet growth factors and to inject them on a surgical site to stimulate the healing process. Leukocyte and platelet-rich fibrin (L-PRF) allows for the preparation of strong fibrin membranes that are enriched with cells (activated platelets, leukocytes, circulating cells) and platelet growth factors.

This autologous healing biomaterial is free of additives such as anticoagulants during blood harvesting or chemicals for activation. In addition, it is simple, inexpensive, and quick to prepare (15 minutes for all steps). The technique that is presented is specifically adapted to the practical needs in daily implant dentistry.

This case letter documents the use of L-PRF during the replacement of a fractured central incisor with an immediate post-extraction implant and crown placement. As a strong solid fibrin membrane, L-PRF is seen to be particularly easy to use in implant dentistry and periodontology. In addition, it offers a protective effect (both mechanical and biological) to the grafted area

12 – Autologus Platelet Rich Fibrin aided Revascularization of an immature, non-vital permanent tooth with apical periodontitis: A case report.

Jadhav GR1, Shah D1, Raghvendra SS1.

J Nat Sci Biol Med. 2015 Jan-Jun;6(1):224-5. doi: 10.4103/0976-9668.149187.

ABSTRACT

Caries or trauma induced non-vital immature permanent tooth with blunderbuss, thin root which are very common among childrens are corrected using regenerative endodontic (revascularization) procedures. In the presented case, a 16-year-old boy reported with chief complaint of pain in maxillary left central incisor (Tooth #21). Tooth #21 showed grade III mobility, draining labial sinus, and short blunderbuss root with diffuse periapical radiolucency. Patient was explained the treatment plan and written informed consent was taken. Platelet rich fibrin (PRF) was prepared according to standard protocol. Autologous PRF was carried to the apical portion of the root canal after inducing revascularization. Access opening was double sealed with MTA and resin modified glass ionomer cement (RMGI). Baseline, 12 month and 18 month follow-up intraoral radiographs were taken. Clinically case was asymptomatic with complete resolution of intraoral sinus. Periapical healing, apical closure, root lengthening and dentinal wall thickening were uneventful. Thus PRF supplementation hastens the predictability and rate of revascularization in non-vital immature permanent teeth.

KEYWORDS: Open apex; PRF; revascularization

13 – A comparative study of platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) on the effect of proliferation and differentiation of rat osteoblasts in vitro.

He L1, Lin Y, Hu X, Zhang Y, Wu H.

Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Nov;108(5):707-13. doi: 10.1016/j.tripleo.2009.06.044.

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the effect of biologic characteristics of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) on proliferation and differentiation of rat osteoblasts.

STUDY DESIGN: Blood samples were collected from 14 healthy volunteers (7 male) with a mean age of 23.2 +/- 2.24 years. PRP and PRF were prepared with standard protocols. The exudates of PRP and PRF were collected at the time points of 1, 7, 14, 21, and 28 days. The levels of platelet-derived growth factor AB (PDGF-AB) and transforming growth factor beta1 (TGF-beta1) were quantified in PRP and PRF. Then the exudates of PRP and PRF were used to culture rat calvaria osteoblasts. The biologic characteristics of osteoblasts were analyzed in vitro for 14 days.

RESULTS: PRP released the highest amounts of TGF-beta1 and PDGF-AB at the first day, followed by significantly decreased release at later time points. PRF released the highest amount of TGF-beta1 at day 14 and the highest amount of PDGF-AB at day 7. Exudates of PRP collected at day 1 and exudates of PRF collected at day 14 expressed maximum alkaline phosphatase (ALP) activity, though no significance was shown. Cells treated with exudates of PRF collected at day 14 reached peak mineralization significantly more than both negative control and positive control groups. PRF is superior to PRP, from the aspects of expression of ALP and induction of mineralization.

CONCLUSIONS: PRF released autologous growth factors gradually and expressed stronger and more durable effect on proliferation and differentiation of rat osteoblasts than PRP in vitro.

Comment in: Selecting a relevant in vitro cell model for testing and comparing the effects of a Choukroun’s platelet-rich fibrin (PRF) membrane and a platelet-rich plasma (PRP) gel: tricks and traps. [Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010]

14 – Platelet Rich Fibrin in the revitalization of tooth with necrotic pulp and open apex.

Shivashankar VY1, Johns DA, Vidyanath S, Kumar MR.

J Conserv Dent. 2012 Oct;15(4):395-8. doi: 10.4103/0972-0707.101926.

ABSTRACT

Regeneration of pulp-dentin complex in an infected necrotic tooth with an open apex is possible if the canal is effectively disinfected. The purpose of this case report is to add a regenerative endodontic case to the existing literature about using Platelet Rich Fibrin (PRF). A nine year old boy who accidently broke his immature maxillary central incisor tooth, developed pulpal necrosis with apical periodontitis. After the access cavity preparation, the canal was effectively irrigated with 20 ml of 5.25% sodium hypochlorite solution and 10ml of 0.2% chlorhexidine solution and dried with paper points. Triple antibiotic paste was placed inside the canal and left for 21 days. 12 ml of whole blood was drawn from the patient’s right antecubital vein and centrifuged for 10 minutes to obtain the Choukroun’s PRF. After the removal of the triple antibiotic paste, the PRF was placed into the canal till the level of cementoenamel junction and 3mm of grey MTA was placed directly over the PRF clot. The setting of MTA was confirmed 3 days later and the tooth was double sealed with GIC and Composite restoration. After 1 year the clinical examination revealed negative responses to percussion and palpation tests. The tooth responded positively to cold and electric pulp tests. Radiographic examination revealed continued thickening of the dentinal walls, root lengthening, regression of the periapical lesion and apical closure. On the basis of the results obtained in our case report we conclude that revitalization of necrotic infected immature tooth is possible under conditions of total canal disinfection and PRF is an ideal biomaterial for pulp-dentin complex regeneration.

KEYWORDS: Open apex; Platelet Rich Fibrin; revitalization

15 – Platelet-rich fibrin-mediated revitalization of immature necrotic tooth.

Mishra N1, Narang I, Mittal N.

Contemp Clin Dent. 2013 Jul;4(3):412-5. doi: 10.4103/0976-237X.118379.

ABSTRACT

Contemporary studies have shown that the regeneration of tissues and root elongation is possible in necrotic immature permanent teeth. The purpose of this case report is to add a new vista in regenerative endodontic therapy by using platelet rich fibrin for revitalization of immature non vital tooth. An 11year old boy with the history of trauma was diagnosed with the pulpal necrosis and symptomatic apical periodontitis in tooth #21. Intra oral periapical radiograph showed open apex and associated immature supernumerary tooth with respect to tooth #21. Access preparation and minimal instrumentation was done to remove necrotic debris under copious irrigation with 2.5% sodium hypochlorite. Triple antibiotic paste was packed in the canal for four weeks. During second visit, 5 mL of whole blood was drawn from the medial cubital vein of the patient and blood was then subjected to centrifugation at 2400 rpm for 12 minutes for the preparation of Platelet rich fibrin (PRF) utilizing Choukroun’s method. Triple antibiotic paste was removed and canal was dried. PRF clot was pushed to the apical region of tooth #21 using hand pluggers. Three milimetres of Mineral trioxide (MTA) was placed in cervical part of the root canal and permanent restoration was done three days later. Clinical examination at 6 and 12 months revealed no sensitivity to percussion and palpation in tooth #21and it responded positively to both electric pulp and cold tests. Radiographic examination showed resolution of periapical rarefaction, further root development and apical closure of the tooth #21 and its associated supernumerary tooth. On the basis of successful outcome of the present case it can be stated that PRF clot may serve as a scaffold for regeneration of necrotic immature teeth.

KEYWORDS: Platelet-rich fibrin; revitalization; triple antibiotic paste

16 – Apical Closure in a Necrotic Immature tooth by Revascularization therapy using Platelet-Rich Fibrin: a Case Report

Fakhr Tabatabaei S1, Bakhtiar H#2, Vatanpour M2, Honarvar M3

Journal of Research in Dentl Sciences – Vol. 11 – No. 4 2015

1 Dentist
2 Assistant Professor, Edodontic Dept, Islamic Azad University, Dental Branch, Tehran, Iran 3Post Graduate Student, Edodontic Dept, Islamic Azad University, Dental Branch, Tehran, Iran

ABSTRACT

Background and Aim: : Revascularization therapy by using Platelet-Rich Fibrin can be a suitable choice for revitalization of immature necrotic teeth as it improves root formation process, thickening of dentinal walls and apical closure. Case Presentation: A 13-year-old girl with a history of trauma in tooth #21 and signs of pulp necrosis referred to the endodontics department of faculty of dentistry of Islamic Azad University. Intraoral radiograph showed immature root with open apex and periapical rarefaction. Access cavity was prepared and the root canal was irrigated with 20 ml of 1/25% sodium hypochlorite solution for 5 minutes and with normal saline. Equal proportions of Ciprofloxacin (tablet, 500mg), Metronidazole (tablet, 500mg) and Cefaclor (capsule, 500mg) were mixed and placed inside root canal for 4 weeks. Then, the canal was irrigated with 17% EDTA. 8 ml of patient’s whole blood was centrifuged for preparation of PRF clot. PRF clot was placed inside the root canal up to CEJ level. MTA of 3mm thickness was placed directly over the PRF clot and tooth was temporarily restored. After 3 days, the tooth was double sealed with Glass Ionomer cement and composite resin. Clinical examinations at 1, 3 and 6 months after, revealed the resolution of periapical lesion, further root development and apical closure. Conclusion: PRF clot is an ideal scaffold for regenerative endodontic therapy in necrotic immature teeth as it contains growth factors and can enhance cellular proliferation and differentiation of stem cells.

Keywords: Immature necrotic teeth, Platelet-Rich Fibrin , Regenerative Endodontics

17 – Surgery Combined with LPRF in Denosumab Osteonecrosis of the Jaw: Case Report.

Maluf G1, Pinho MC2, Cunha SR3, Santos PS4, Fregnani ER2.

Braz Dent J. 2016 May-Jun;27(3):353-8. doi: 10.1590/0103-6440201600662.

ABSTRACT

This paper describes two cases in which the use of leucocyte-rich and platelet-rich fibrin (LPRF) combined with bone resection did not result in complete tissue response in the treatment of medication-related osteonecrosis of the jaw (MRONJ). It has been recently described in patients receiving subcutaneous administration of RANK-inhibitors, such as Denosumab, and anti-angiogenic drugs, such as Bevacizumab, as observed in our cases. Due to promising results in recent studies, more patients will receive these medications in order to avoid skeletal complications due to metastatic bone disease and, therefore, this scenario has a potential to become a comparable challenge to the bisphosphonate- induced jaw necrosis in the area of Oral and Maxillofacial Surgery. No convincing surgical technique has been described to overcome the non-healing mucosal lesions with exposed bone due to RANK-inhibitor therapy. Based o n the findings in the literature and in both cases described herein can be concluded that the use of LPRF should be considered in the treatment of patients with DRONJ.