EGYPTIAN Vol.

63, 335:343, January, 2017

DENTAL JOURNAL I.S.S.N 0070-9484

Oral Surgery
www.eda-egypt.org • Codex : 189/1701

A NEW TECHNIQUE OF CLOSURE OF ORO-ANTRAL

FISTULA BY USING PLATELET RICH FIBRIN MEMBRANE
IN COMPARISON WITH BUCCAL ADVANCEMENT FLAP

Wael Mohamed Said Ahmed*

ABSTRACT
Background: Platelet rich fibrin (PRF), a concentrate of platelets and leucocytes embedded in
a fibrin matrix has many applications in the field of oral and maxillofacial surgery. However, its use
in the closure of oroantral fistula (OAF) has not been reported.

Purpose: This study aimed to compare the efficacy of using PRF membrane with acrylic splint
versus the traditional buccal advancement flap for closure of OAF.

Patients and methods: 20 patients with OAFs were included in this study. Patients were
randomly divided into two equal groups. Closure of OAF for (group I) with the buccal advancement
flap, while for (group II) with the PRF membranes was done. Patients were clinically evaluated for
primary closure, pain, edema, and depth of the sulcus postsurgically.

Results: Patients were 14 males and 6 females, with a mean age of 42.6 years. 19 cases of
OAFs occurred after extraction of upper posterior teeth and 1 case occurred after cyst enucleation.
Uneventful healing occurred in 18 patients; 9 in each group. Postoperative pain and postoperative
edema were significantly less in group II than in group I.

Conclusion: PRF membrane is an appropriate alternative technique for closure of OAF,

with less postoperative pain and edema than buccal advancement flap technique.

INTRODUCTION The most common cause of OAC is the extraction

of upper posterior teeth (80%), mainly the first and
Oroantral communication (OAC) is an abnormal
second maxillary molars, as a result of close anatomic
opening between maxillary sinus and oral cavity.
relation between their root apices and the maxillary
If left untreated, the opening becomes lined by sinus floor, which may be separated from each other
antral and oral epithelium forming oroantral fistula by 0 to 7mm of bone.2,3 OAC can also occur as a
(OAF).1 result of cysts, trauma, infection, and tumors.4

* Lecturer of Oral & Maxiollofacial Surgery, Faculty of Dentistry, Mansoura University.

(336) E.D.J. Vol. 63, No. 1 Wael Mohamed Said Ahmed

OAC less than 2mm can heal spontaneously, anticoagulant, bovine thrombin or calcium chloride),
provided that there is no sinus inflammation, while and can be prepared as a membrane.19 PRF consists
more than 3mm, or even smaller with sinusitis, of a huge quantity of platelet and leukocytes (97%
mostly needs surgical closure.5 Small perforations of platelets and 60% of leukocytes of the centrifuged
can heal spontaneously within 2 to 14 days. Surgical blood volume) embedded in a matrix of autogenous
closure of OAF -even in small perforations- is highly fibrin. This concentrate contains a large amount of
recommended after 2 weeks, as the possibility of many growth factors that play an important role in
spontaneous healing declines after that period.6 healing of both soft and hard tissues.20,21

Different methods have been used for closure PRF has many applications in the field of oral
of OAF including autogenous soft tissue flaps, and maxillofacial surgery. It can be used for sinus
autogenous hard tissue grafts, allografts, xenografts, lift augmentation, horizontal and vertical ridge aug-
and alloplastic materials.7 mentations, ridge preservation grafting, periodontal
defects, alveolar cleft repair, reconstruction of de-
Buccal, palatal, buccal bad of fat, and tongue fects after cyst enucleation or tumor excision, heal-
flaps are the most commonly used autogenous ing of extraction wounds, endodontic surgeries and
soft tissue flaps.4,8Hard tissue autografts including to treat gingival recession.22-28
bone,9 cartilage grafts,10 and third molar auto-
transplantation11 have been used successfully for This study aimed to compare the efficacy of
closure of OAF. Buccal advancement flap was using PRF membrane with acrylic splint versus
designed by Rehrmann in 1936.12 It is the most buccal advancement flap for closure of OAF. Null
common surgical technique used for closure of hypothesis: no difference; relative hypothesis: PRF
OAF, as it has a high success rate because it is easy, membrane would be an appropriate alternative
technique than buccal advancement flap for soft
simple and it also ensures an adequate blood supply
tissue closure the OAF.
from its wide base.13
Many allogenic and xenogenic grafts have PATIENTS AND METHODS
been used successfully in closure of OAF such
This study was approved by the ethical
as lyophilized fibrin glue14, lyophilized dura of
committee of Mansoura University. The guidelines
human origin15and Bio-Oss(bovine bone)& Bio-
of the Helsinki Declaration were followed. Twenty
Gide(porcine collagen membrane) Sandwich
patients with OAF were included in this study(fig1).
technique16.
Patients were presenting to the outpatient clinic of
Various alloplastic materials have been used for the Oral and Maxillofacial Surgery Department,
closure of OAF. Though alloplastic materials have Faculty of Dentistry, Mansoura University between
the advantages of simple use, some disadvantages 2014 -2016. Patients were informed about the
like time consuming, high expense, and increase line of treatment and the expected postoperative
incidence of infection limit their use as a usual complications. Every patient signed an informed
surgical technique for closure of OAF.16,17 consent prior to treatment.
Platelet rich fibrin (PRF) has been considered According to the method of OAF closure, patients
as the second generation of platelet concentrate, were randomly divided into two equal groups:
and it was first described in France by Choukroun
Group I: OAFs were closed using buccal
et al.18 PRF has many advantages over the first
advancement flap.
generation of platelet rich plasma(PRP) including
ease of preparation and handling, minimal cost, Group II: OAFs were closed using PRF
and lack of biochemical additives (i.e., no need for membranes with occlusal splints.
A NEW TECHNIQUE OF CLOSURE OF ORO-ANTRAL FISTULA (337)

Fig. (1) a) OAF, b) Preoperative panoramic X-ray showing OAF (arrow).

All patients with sinusitis were prepared 3 to Group II: closure of OAFs using PRF membranes
5 days before surgical closure of OAF, with oral
For each patient in this group, alginate impression
administration of Sultamicillin (Unictam, MUP,
was taken for the upper jaw and poured with dental
Egypt) 375 mg 3 times/day, or erythromycin (Eryth-
stone. A model was made where a simple acrylic
romycin, Pharco, Egypt) 500 mg 3 times/day if the
splint was fabricated to cover PRF membrane after
patient was allergic to penicillin, and maxillary si-
nus lavage by using 1 % povidone-iodine (Betadine, closure of the OAF.
Nile/MundiPh, Egypt) through OAF.
Preparation of PRF membrane:
Surgical procedures: A 10 ml of blood was withdrawn from the
After induction of local anesthesia, 3-4 mm patient’s antecubital vein. The blood sample was
of the soft tissue around the orifice of OAF was collected in glass-coated plastic tube without
incised, as the soft tissue opening is usually smaller anticoagulant, then immediately centrifuged at
than the bony opening. Then the unhealthy soft and 3,000 rpm for 10 minutes.18 After centrifugation, the
osseous tissues were removed. resultant product consisted of three layers: acellular
plasma forming uppermost layer, PRF in the middle,
Group I: closure of OAFs using buccal advance-
and RBCs forming the basal layer (fig 3a).
ment (Rehrmann) flap12:
The PRF clot was separated from RBCs layer
Trapezoidal mucoperiosteal flap was made with
and packed tightly in between 2 sterile gauzes to
wide base at the buccal sulcus to ensure sufficient
form PRF membrane (fig 3b). The PRF membrane
blood supply. After elevation of the flap from the
alveolar bone, horizontal releasing incisions were was immediately used to cover the OAF. The
made through the periosteum at the base of the flap PRF membrane was tucked below the buccal and
for its extension if necessary (fig 2a). Water tight palatal mucoperiosteum (fig 3c) and secured with
closure was achieved by suturing the apex of the them using 3/0 silk suture. The fitting surface of
flap with palatal mucosa without tension and then the acrylic splint was then relieved and inserted
the vertical incisions using 3/0 silk sutures (fig 2b). intraorally to cover PRF membrane (fig 3d).
(338) E.D.J. Vol. 63, No. 1 Wael Mohamed Said Ahmed

Fig. (2) a) Elevation of the buccal trapezoidal mucoperiosteal flap, b) Water tight closure of the buccal advancement flap.

Fig. (3) a) The resultant product after blood centrifugation: acellular plasma in the top, PRF in the middle and RBCs in the base,
b) PRF clot attached to RBCs layer, c) Tucking of the PRF membrane below the buccal and palatal mucoperiosteum, d)
Intraoral insertion of the acrylic splint to cover PRF membrane.
A NEW TECHNIQUE OF CLOSURE OF ORO-ANTRAL FISTULA (339)

Postoperative instruction: Quali­tative data were presented in number and

Every patient was given sultamicillin 375 mg percentage. Student’s t-test was used for comparing
3times/day or erythromycin 500 mg 3 times/day quantitative parametric data. Mann Whitney U test
if the patient was allergic to penicillin and xylo- was used for comparing quantitative non-parametric
metazoline HCL (Otrivin, Novartis, Switzerland) data. Chi-square “χ2” or Fischer’s exact tests, as
nasal decongestant drops 4 times/day for 5 days indicated, were used to compare the qualitative data.
after surgery. Diclofenac potassium (Oflam, me- P value less than 0.05 was considered sta­tistically
pha, Switzerland) 50 mg was prescribed to be taken significant.
when required. Patients were instructed to use 2 %
chlorhexidine mouth wash (Hexitol, Adco, Egypt) RESULTS
3 times daily for 2 weeks postsurgically. Patients in This study included 14 males and 6 females
group II were instructed to wear the splint continu- with no significant difference between the 2 groups
ously for the next 2 weeks and to remove it only regarding sex (P=1). The mean age of patients was
during the use of mouth wash and for its cleans- 42.6 years (group I; 40.9, group II; and 44.2) with
ing. Patients were advised not to blow their cheeks no significant difference between the 2 groups
or nose, avoid smoking, and avoid sneezing with regarding age (P=0.49). 19 cases of OAF occurred
closed mouth during the first month after surgery. after extraction of upper posterior teeth; 2, 13,3, and
After 2 weeks postsurgically, sutures were removed. 1 cases after extraction of 2nd premolar, 1st molar, 2nd
Evaluation: Clinical examinations were molar, and 3rd molar respectively. One case occurred
scheduled at 3 days, 2, 4 and 12 weeks postoperatively after cyst enucleation from right posterior maxilla in
for evaluation primary closure, pain, edema, and group II. There was no significant difference between
depth of the sulcus outcomes. the 2 groups regarding cause (P=0.66). The incidence
of OAF was equal in both sides (P=1). (tabl.1)
· Success of surgery was considered when there was
complete closure of the OAF with oral mucosa.
TABLE (1) Age, gender of the patients, site and
· Postoperative pain and edema were assessed after causes of OAFs in group I and group II:
3 days postsurgically. Postoperative pain was as-
sessed using visual analogue scale (VAS) of 10 Treatment
units: 0; no pain, 1-2; mild pain, 3-6; moderate P
Group I Group II
pain, 7-9; severe pain, and 10; inconsolable pain.
Age 40.90±9.43 44.20±11.80 0.49
· Postoperative edema was assessed by measuring
F 3 30.0% 3 30.0%
the difference between preoperative and 1.00
Sex

postoperative measurements of the following M 7 70.0% 7 70.0%

lines: line A; from the outer canthus of the eye Left 5 50.0% 5 50.0%
1.00
Side

to the angle of the mandible, and line B; from Right 5 50.0% 5 50.0%
the tragus to the corner of the mouth.
Cyst 0 0.0% 1 10.0%

Statistical analysis: Ext. 5 1 10.0% 1 10.0%

Cause

Ext. 6 7 70.0% 6 60.0% 0.66

Data were analyzed using Statistical Package for
Social Science software computer program version Ext. 7 1 10.0% 2 20.0%
17 (SPSS, Inc., Chicago, IL, USA). Quantitative Ext. 8 1 10.0% 0 0.0%
data for parametric data were presented in mean
Data expressed either as mean±SD or as frequency
and standard deviation and median and IQR
(interquartile range) for non-parametric data. P significance <0.05
(340) E.D.J. Vol. 63, No. 1 Wael Mohamed Said Ahmed

Primary outcome (success /failure) (tab.2): Pain, edema & sulcus depth outcomes:
· In group I: uneventful healing occurred in 9 Evaluation of postoperative pain (tab.3):
patients (fig 3a), and closure failure occurred
· In group I: pain score ranged from 2.0 to 6.0,
in one patient. With this patient there was a
with median 3.50, and IQR (3.00-5.00). In
dehiscence of the buccal flap with persistence
group II: pain score ranged from 0.0 to 4.0,
OAF.
with median 2.0, and IQR (1.00-3.00). There
· In group II: uneventful healing with complete was significant difference between group I and
closure and rapid epithelization of the OAF group II regarding pain (P=0.015).
occurred in 9 patients(fig 3b). Failure occurred in
Evaluation of postoperative edema(tab.3):
one patient where the PRF membrane detached
from the surrounding mucosa with persistence Postoperative edema (line A):
of OAF. · In group I, the difference between preoperative
and postoperative measurements of line A ranged
TABLE (2) Postoperative primary closure outcomes from 0.2 to 2 cm, with median 1.15 cm and IQR
for group I and group II: (0.90-1.50). In group II; the difference ranged
from 0.1 to 0.7 cm, with median 0.35 cm, and
IQR (0.30-0.50). These line A measurements of
Treatment P
postoperative edema were significantly different
between group I and group II (P<0.001).
Group I Group II
Postoperative edema (line B):
Failure 1 10.0% 1 10.0% 1.00
Success · In group I, the difference between preoperative
or failure and postoperative measurements of line B
Success 9 90.0% 9 90.0%
ranged from 0.6 to 2.3 cm, with median 1.35cm
and IQR (1.00-1.70). In group II; the difference
Data expressed as frequency
ranged from 0.2 to 0.8 cm, with median
P significance <0.05 0.35cm, and IQR (0.30-0.70). These line B

Fig. (3) a) Complete closure of the OAC in group I, after 1 month postsurgically with decrease in the depth of the buccal sulcus
(arrow), b) Healed OAC after 1 months postsurgically in group II.
A NEW TECHNIQUE OF CLOSURE OF ORO-ANTRAL FISTULA (341)

measurements of postoperative edema were In group I, uneventful closure of OAFs occurred

also significantly different between group I and in 9 patients (90%), this may be attributed to the
group II (P<0.001). design of buccal flap as it has a wide base which
ensures good blood supply to the flap. Decrease of
Table (3): Postoperative pain and edema outcomes: the depth of the sulcus- which can interfere with
prosthetic rehabilitation and maintenance of oral
Treatment hygiene- occurred in all patients. von Wowern29
found permanent decrease of vestibular depth in half
Group I Group II P
(16 cases) of the buccal flap cases. He considered
Median IQR Median IQR flattening of vestibule for 2 months results in a
Pain score 3.50 3.00-5.00 2.00 1.00-3.00 0.015
permanent condition. Currently, due to the wide
use of implant-retained prosthesis, reduction in the
Line A(cm) 1.15 .90-1.50 .35 .30-.50 <0.001 buccal sulcus depth becomes less problematic.
Line B(cm) 1.35 1.00-1.70 .35 .30-.70 <0.001
In group II, the success of PRF in closure
of OAF occurred in 9 cases (90%), this may be
Data expressed as median – IQR
attributed to: first, PRF membrane acts as a fibrin
P significance <0.05 bandage that accelerates the healing of the wound
edges, permits a rapid epithelization of the surface
Evaluation of the depth of the buccal sulcus:
of OAC and form an effective mechanical barrier
Depth of the buccal sulcus decreased and did not against epithelial cell, oral bacteria, and irritants to
return to normal even after 3 months in all cases of penetrate the OAC.22,30
group I. While in group II there was no change in
Second, fibrin acts as a scaffold in which
the buccal sulcus depth in all cases. cells may proliferate, organize, and perform their
functions.31 Fibrin provides a matrix for migration of
DISCUSSION fibroblasts and endothelial cells, which are involved
Ideally, treatment of OAF is simple, easy, safe, in the angiogenesis process and are responsible in
and it has a low cost. Also, it provides adequate the healing of new tissues.32
healing of both osseous and soft tissues, and with Third, the platelet growth factors such as platelet-
minimal complications. However, such a treatment derived growth factor, transforming growth factor
actually does not seem to exist.7 β, fibroblast growth factor, and vascular endothelial
growth factor are slowly released as the fibrin matrix
Several surgical techniques have been proposed
is resorbed especially during the first 7-14 days, but
for treatment of OAFs. These techniques have
if fibers are cross-linked as by tight compression it
their advantages and disadvantages with only a
could provide resistance to enzymatic degradation
few having gained wide acceptance. However, the
and could be more stable during the healing time.33,34
most frequently used techniques are the buccal and Zumstein et al.35 reported that the release of platelet
palatal flaps. growth factors can be continued up to 28 days.
Control of sinusitis prior to surgery was Fourth, occlusal splint was used to cover and
mandatory in success of OAF closure. von protect the PRF membrane during the healing time.
Wowern29 documented 98% closure success of OAF It was used also to overcome the main drawbacks of
in patients with preoperative control of sinusitis that PRF membrane, which are its lack of rigidity, and
was decreased to 79 % in patients with sinusitis. can only be prepared in thin thicknesses.36
(342) E.D.J. Vol. 63, No. 1 Wael Mohamed Said Ahmed

Pain and postoperative edema were significantly 7. Visscher SH1, van Minnen B, Bos RR: Closure of oro-
less in group II than group I, this may be attributed antral communications: a review of the literature. J Oral
to first; less surgical steps in group II as it needed Maxillofac Surg 68(6):1384, 2010.
only slight reflection of buccal and palatal flaps 8. Stewart K, Lazaw. Surgical management of oroantral fistu-
rather than trapezoidal mucoperiosteal flap and la: flap procedures. Op Tech Otolaryngol Head Neck Surg
horizontal relaxing incisions in group I. 10(2):148, 1999.

Second; the presence of cytokines and leukocytes 9. Watzak G, Tepper G, Zechner W, Monov G, Busenlechner
that are concentrated in PRF membrane can play D, Watzek G. Bony press-fit closure of oro-antral fistulas:
an important rule as anti-inflammatory and anti- a technique for pre-sinus lift repair and secondary closure.
J Oral Maxillofac Surg 63(9):1288, 2005.
infectious materials, respectively.33 Kumar et al.37
and Singh et al.38 concluded decrease in postoperative 10. Isler SC, Demircan S, Cansiz E. Closure of oroantral fis-
pain and swelling after surgical extraction of lower tula using auricular cartilage: a new method to repair an
third molars when using PRF. Also, Dohan et al.39 oroantral fistula. Br J Oral Maxillofac Surg 49(8):86, 2011.
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and anti-inflammatory properties. of third molar transplantation for closure of the oroantral
communication after tooth extraction: a report of 2 cas-
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was concluded that PRF membrane is an appropriate
95(4):409, 2003.
alternative technique for closure of OAF. Compared
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