Review Is platelet-rich fibrin really useful in oral and maxillofacial

Review
Is platelet-rich fibrin really useful in oral and maxillofacial
surgery? Lights and shadows of this new technique
Abstract
D Lauritano1*, A Avantaggiato2, V Candotto2, I Zollino2, F Carinci2
Introduction
The healing of hard and soft tissues is
mediated by a wide range of intra and
extra-cellular events that are regulated by protein signals. It is known
that platelets are involved in the process 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 anticoagulant free blood harvest. Platelet-rich
fibrin is similar to a fibrin network
that allows cell migration and proliferation 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 stimulate the surrounding environment
to a more rapid wound healing. This
review aims to analyse the clinical
results of platelet-rich fibrin in periodontology, oral surgery and head
plastic surgery.
*Corresponding author
Email: [email protected]
Department of Interdisciplinary Surgery and
Medicine, University Milano Bicocca, Milan,
Italy
2 Department of Morphology, Surgery and
Experimental Medicine, University of Ferrara,
Ferrara, Italy
1 Conclusion
The 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 leucocyte- and platelet-rich fibrin will
continue to develop in oral and maxillofacial surgery in the next years.
Introduction
Platelet concentrate fibrin is an evolution 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 surgical wounds. This platelet suspension, defined as platelet-rich plasma
(PRP), as the platelet concentrate
used in transfusional medicine, is
the precursor of another autologous 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 different platelet concentrates divided
them into four different categories
depending on the leukocytes 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 plaletetrich 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 failures 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 periodontics, 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.
Discussion
PRF applications in
­periodontology
The topical use of platelet concentrates is recent, and its efficiency
remains controversial in periodontology for treatment of gingival
recession. A 6-month randomised
controlled clinical study has compared the results achieved by the use
of a PRF membrane or connective
Licensee OA Publishing London 2013. Creative Commons Attribution License (CC-BY)
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.
Competing interests: none declared. Conflict of interests: none declared.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
Emerging Technologies
Page 1 of 5
Page 2 of 5
Review
Other studies investigated the
clinical and radiological effective­
ness of autologous PRF in the treatment 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 promotes bone regeneration in periodontal defects, thereby reducing
PD, improving CALs and promoting
defect filling16.
PRF and oral surgery
The regenerative medicine techniques 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 process then occurs and allows for the
easy collection of a L-PRF clot, without the need for any biochemical
modification of the blood, that is, no
anticoagulants, thrombin or calcium
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
Figure 2: Kit for blood sampling.
Figure 3: Blood separation after
centrifugation.
Figure 1: Centrifuge.
Figure 4: PRF as it appears after
centrifugation.
Licensee OA Publishing London 2013. Creative Commons Attribution License (CC-BY)
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.
Competing interests: none declared. Conflict of interests: none declared.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
tissue graft (CTG) in the treatment of
gingival recession and evaluated the
clinical impact of PRF on early wound
healing and subjective patient discomfort. 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 demonstrate any clinical advantage of
the use of PRF compared to enamel
matrix derivative in the coverage
of gingival recession with the coronally 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 compared to an MCAF alone for the treatment of multiple gingival recessions.
In fact the addition of a PRF membrane 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 concentrates widely used in surgery to
facilitate wound healing. Another
study evaluated the effectiveness of
PRF and PRP in the treatment of periodontal intrabony defects in chronic
periodontitis. The results showed
similar pocket depth (PD) reduction, clinical attachment level (CAL)
gain, and bone filling at sites treated
with PRF or PRP compared with conventional open-flap debridement.
Because PRF is less time consuming
and less technique sensitive, it may
seem a better treatment option than
PRP12.
Page 3 of 5
Figure 5: PRF ready for surgical
applications.
because different suppliers use similar nomenclature for their distinct
products (such as Vivostat PRF and
Fibrinet Platelet-Rich Fibrin Matrix)18.
Bone regenerative techniques
include sinus lift for implant placement, 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 implantation seems to be a reliable surgical option promoting natural bone
regeneration19–23.
Early reviews of the osteotomemediated 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 engineering. 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 anatomical position to facilitate a functional and aesthetic rehabilitation.
However, this is not always possible,
and in some cases techniques of alveolar 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 concentrate 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 techniques and potential healing difficulties associated with membranes, and
less resorption during healing, as
compared to guided bone regeneration 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 augmentation 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 surgery
It’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 accelerate wound healing. The use of a new
preparation, platelet- rich fibrin
matrix (PRFM) for plastic surgery of
the face, such as volume augmentation, fat transfer supplementation,
represent a new technique in aesthetic surgery31. In fact injection of
PRFM into the deep dermis and subdermis of the skin stimulates a number of cellular changes that can be
harnessed for use32,33.
Although platelet concentrates
have enjoyed some success in plastic 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 without tissue manipulation. The PRF
produces an autologous and natural
platelet concentrate that releases
growth factors and stimulates the
regeneration of the surrounding tissues 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 autografts. The results have concluded
that epithelialisation of donor
wounds or the interstices of autografts was not significantly influenced 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 efficacy of the platelets concentrates for
adipocyte grafts. The results suggest
that the combination of fat grafts and
PRF is more effective than the combination of fat and PRP for facial lipostructure surgery36.
Conclusion
The use of PRF allowed the reconstruction of the alveolar ridges at
the gingival and bone levels. The PRF
Licensee OA Publishing London 2013. Creative Commons Attribution License (CC-BY)
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.
Competing interests: none declared. Conflict of interests: none declared.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
Review
Page 4 of 5
makes it possible to overcome some
technical limitations of an implantsupported 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 maxillofacial 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, inexpensive 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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Licensee OA Publishing London 2013. Creative Commons Attribution License (CC-BY)
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.
Competing interests: none declared. Conflict of interests: none declared.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
Review
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Licensee OA Publishing London 2013. Creative Commons Attribution License (CC-BY)
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.
Competing interests: none declared. Conflict of interests: none declared.
All authors contributed to the conception, design, and preparation of the manuscript, as well as read and approved the final manuscript.
All authors abide by the Association for Medical Ethics (AME) ethical rules of disclosure.
Review