clinical cases - Dental and Medical Problems

CLINICAL CASES
Dent. Med. Probl. 2014, 51, 2, 252–258
ISSN 1644-387X
© Copyright by Wroclaw Medical University
and Polish Dental Society
Daniel Ciapiński1, B–C, Iwona Niedzielska1, D–F, Andrzej Witowski2, B
A Suggestion as to Guided Regeneration
of Bone Defects After Cystectomy
– Case Report
Propozycja sterowanej regeneracji dużych ubytków pocystektomijnych
– opis przypadku
1
2
Department of Cranio-Maxillo-Facial and Oral Surgery, Medical University of Silesia, Katowice, Poland
Clinic of Anesthesiology and Intensive Care, Medical University of Silesia, Katowice, Poland
A – research concept and design; B – collection and/or assembly of data; C – data analysis and interpretation;
D – writing the article; E – critical revision of the article; F – final approval of article
Abstract
The methods used to treat small cysts are well-established and undisputable. Nowadays, the process of bone regeneration for future implants and prosthetic treatment is supplemented by inserting bone-replacement materials
into such defects. A problem arises in the case of large cysts, where bone-replacement materials cannot be used to
secure proper bone regeneration. After operations on large mandible cysts, the patients are often compelled to use
an obdurate for a period of about 2 years to heal the site or decompress the cyst. This makes the treating process
very strenuous and long for patients. On the other hand, an excellent alternative seems to be the use of autogenic
materials causing no significant mutilation or severe complications. Currently, the best in the regeneration of bone
is considered to be autogenously materials that have not only osteoconductive properties, but also osteoinductive
and osteogenic. However, it is important to note that obtaining this material was the least burdensome for the
patient and it was possible to collect a large amount of tissue. Based on the case presented in this paper, we suggest
a tibiae bone as a donor place and platelet rich fibrin as a membrane covering the material and support rapid healing (Dent. Med. Probl. 2014, 51, 2, 252–258).
Key words: guided bone regeneration, bone defect, autogenic bone graft, platelet-rich fibrin.
Streszczenie
Metody stosowane w leczeniu małych torbieli są ugruntowane i niepodważalne. Obecnie proces regeneracji kości
pod przyszłe leczenie implantologiczne oraz protetyczne polega na uzupełnieniu defektów kostnych materiałami
kościozastępczymi. Pojawia się problem w przypadku dużych torbieli i dużych ubytków kości, ponieważ materiały kościozastępcze w tych przypadkach nie mogą być zastosowane. Po zabiegach chirurgicznych usunięcia dużej
torbieli żuchwy pacjenci są często zmuszani do korzystania z obturatora przez około 2 lata w celu zmniejszenia
i dekompresji torbieli. To powoduje, iż leczenie staje się długie i męczące dla pacjentów. Doskonałą alternatywą
wydaje się jednak zastosowanie materiałów autogennych, które nie powodują znacznego okaleczenia oraz licznych komplikacji. Obecnie za najlepsze w regeneracji kostnej uważa się materiały autogenne, które mają nie tylko
właściwości osteokondukcyjne, lecz także osteoindukcyjne i osteogenne. Ważne jest jednak, aby pozyskanie tego
materiału było jak najmniej obciążające dla pacjenta oraz możliwe było pobranie dużej ilości tkanek. Opierając się
na przypadku opisanym w pracy, autorzy proponują kość piszczelową jako miejsce dawcze oraz fibrynę bogatopłytkową jako membranę pokrywającą przeszczepiony materiał i wspomagający jego szybkie wgajanie (Dent. Med.
Probl. 2014, 51, 2, 252–258).
Słowa kluczowe: fibryna bogatopłytkowa, sterowana regeneracja kości, autogenny przeszczep kości, ubytek
kostny.
Guided Regeneration of Bone Defects After Cystectomy
Odontogenic cysts are usually treated by surgical methods [1]. To avoid neoplastic metaplasia
of the cyst lining epithelium (some authors report
that this occurs in 17% of the cases), most odontogenic cysts are treated by one-stage procedure [1].
In the past, large cysts were most often treated by
two-stage methods as suggested by Drozdowski
(modified Partsch I) due to the high risk of pathological fractures. Stage 1 consists of cutting a hole
into the cyst cavity through the layers between the
mouth and the cyst lumen. The hole is preserved
by means of an obturator until the time a radical
procedure can be performed. Stage 2, i.e. enucleation of the cyst, is performed when the cyst becomes small enough to remove it safely for adjacent anatomical structures and teeth. Disadvantages of this method are long duration of the
treatment, necessity to perform two operations,
discomfort connected with the necessity to use an
obturator or to observe special regulations of oral
hygiene, and possible neoplastic transformation of
the cyst lining [2].
One-stage (Partsch I) treatment consists of
enucleating the cyst sac with its contents and closing the postoperative wound [1]. The bone cavity
becomes filled with clot that will undergo gradual
organization and regeneration resulting finally in
fibrous or bone tissue. Apart from the morphology
of the defects, one of the most commonly reported
local factors restricting the regeneration processes
is their size. So-called critical size defects (CSDs)
will not be filled with good bone tissue. Studies on
human patients have shown that CSD values range
most often from 5 mm to 7 mm. If the defects are
greater, the plasma will extravasate, causing the retraction and isolation of the fibrin marginal layer
from its walls. As a result, mesenchymal cells will
fail to penetrate properly the defect, and the blood
clot will be replaced by connective tissue. This may
lead to the development of scar tissue [3]. Systemic factors also have a great impact on bone healing, as well as bone loss itself, its shape, the volume
of the spatial arrangement. Therefore, the surgical
treatment of cysts larger than 7 mm will require
special attention, aside from the enucleation of the
lesion, so as to stimulate correct bone reconstruction, in terms of volume and quality, in the defect
site, that will facilitate in the future application of
prostheses, conventional or implantological, after
the bone has regenerated.
Methods of treatment used in order to fill intraosseous defects with good bone tissue are commonly called guided bone regeneration (GBR).
A combined therapeutic approach, consisting of
filling the defect with augmentation material, covering it with a barrier membrane and closing the
wound is considered by the majority of authors as
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the best way of treating intraosseous defects [4].
Alloplastic bone-replacement materials, xenogenic or allogenic materials and autogenic bone grafts
are currently being used to fill bone defects [5, 6].
Among a wide variety of reconstructive materials used in medicine, the patient’s own tissue (autogenic material) in the form of bone chips or
blocks, harvested and grafted at the same time,
is definitely the best [7]. Such a material activates
three important mechanisms: osteogenesis, i.e.
creating bone tissue as a result of transferring progenitor cells which undergo differentiation into
osteoblasts, osteoinduction, i.e. stimulating mesenchymal cells through bone morphogenetic proteins (BMPs) to differentiate into osteoblasts, and
osteoconduction, i.e. creating a skeleton to enable
bone tissue growth. The bone can be harvested intraorally or extraorally. Inside a mouth, the bone is
usually harvested from retromolar regions in the
mandible, mentum, maxillary tuber or edentulous
maxilla, but the volume of such bone is limited. If
larger defects must be filled, the bone is harvested from remote places, most often from the iliac
ala, rib, parietal bone or shank bone. In the case
of cancellous bone grafts, the greatest volumes are
obtained from the iliac crest and proximal tibial
metaphysis [6]. Platelet-rich fibrin (PRF) is used to
isolate the autogenic graft that has been placed to
fill the defect after a cystectomy from the mucoperiosteal flap, and for its regenerative and healing
properties. Platelet-rich fibrin is a product of peripheral blood centrifugation, and it contains plasmatic growth factors like platelet-derived growth
factor (PDGF), insulin growth factor (IGF), transforming growth factor β (TGF-β), vascular endothelial growth factor (VEGF), epidermal growth
factor (EGF), hepatocyte growth factor (HGF) and
cytokinins. The autogenic nature of the material eliminates the danger of a cross infection developing. Although immunogenic, the material
shows strong tissue-forming potential. Dense fibrin network of PRF together with PDGF content
inhibit the growth of keratocytes into the postoperative wound, and make favourable conditions
for reconstructing physiological structures [8,9].
Ease of preparation and manipulation combined
with low costs make PRF a reasonable alternative
for artificial resorbable and nonresorbable barrier membranes. There are reports on using PRF
in periodontology and implantology, both as clots
immediately after centrifugation and as ready
membranes.
A total of 23 cystectomies of large cysts, using
tibial bone chips and platelet-rich fibrin, were performed in Department and Hospital of Maxillofacial and Oral Surgery, Katowice, between 2010 and
2012. Healing of the donor or recipient sites was
254
correct and bone reconstruction normal in most
of the patients. One of the cases is presented below
to show some details of the procedure.
Case Report
A 33-year-old woman B.K. (case record
no.10/654C) was referred by her family doctor to
Outpatient Clinic of Maxillofacial and Oral Surgery, Silesian Medical University, Katowice, on
18 August 2010 because of tissue deformation in
the region corresponding to molar teeth 46 and 47
which she had observed a few weeks before. She
used medical drugs (Propranolol 10 mg 3 × 1 tabl.
daily, Amertil 10 mg 1 × 1 tabl. daily and Buderhin 1 × 1 one dose to each nostril) due to systemic
diseases (arterial hypertension, cardioneurosis, allergy to pollen from trees, grasses and corn). Her
history revealed nephrotic syndrome in childhood
and radical operation on her right middle ear for
Fig. 1. Pantomographic x-ray picture of the patient
before operation
Ryc. 1. Zdjęcie RTG pantomograficzne pacjentki przed
zabiegiem chirurgicznym
D. Ciapiński, I. Niedzielska, A. Witowski
cholesteatoma in 2005. Intraoral examination revealed ectatic mandibular body around 47–48 and
necrotic pulp with 25, 27. A pantomography revealed a follicular cyst in tooth 48 and an impacted tooth 47 (Fig. 1, 2). Upon adequate preparation,
including sanation of the mouth, the patient was
admitted to Hospital of Maxillofacial Surgery in
Katowice on 27 September 2010. Cystectomy was
performed together with the removal of the impacted teeth in a standard way. A hole was planned
across the compact bone with the diameter sufficient to allow enucleation of the entire cyst sac
(Fig. 4). Donor site bone (Fig. 3, 5) was harvested upon making an incision on the skin and subcutaneous tissue 2 cm below and medially from
the right tibial tubercle, removing the compact
bone with a trephine and curetting the cancellous
Fig. 3. Radiograph of shanks before operation
Ryc. 3. Zdjęcie RTG podudzi przed zabiegiem operacyjnym
Fig. 2. Pantomographic x-ray picture of the patient
before operation: close-up
Fig. 4. Operation – mandibular bone defect upon
removal of the cyst together with impacted teeth
Ryc. 2. Zdjęcie RTG pantomograficzne pacjentki przed
zabiegiem chirurgicznym – zbliżenie
Ryc. 4. Zabieg chirurgiczny – ubytek kostny żuchwy po
usunięciu torbieli z zatrzymanymi zębami
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Guided Regeneration of Bone Defects After Cystectomy
Fig. 7. Operation – platelet-rich fibrin (PRF)
Ryc. 7. Zabieg chirurgiczny – fibryna bogatopłytkowa
(PRF)
Fig. 5. Operation – surgical approach to the donor site
i.e.right proximal tibial metaphysic
Ryc. 5. Zabieg chirurgiczny – dostęp operacyjny do
miejsca dawczego (nasady bliższej kości piszczelowej
prawej)
Fig. 8. Operation – using a cancellous bone graft to
augment the bone defect
Fig. 6. Operation – cancellous bone harvested from
the right tibia
Ryc. 8. Zabieg chirurgiczny – augmentacja ubytku
kostnego przeszczepem kości gąbczastej
Ryc. 6. Zabieg chirurgiczny – pobrana kość gąbczasta
z kości piszczelowej prawej
bone chips. The chips (5 cm3) were inserted into
the mandibular defect (Fig. 6, 8) and covered with
PRF membranes (Fig. 7, 9). PRF membranes were
prepared through centrifugation of peripheral vein
fresh blood (48 mL). The wounds in the mouth and
lower limb (Fig. 10) were treated surgically.
The patient received antibiotic prophylaxis after the operation: Taromentin 3 × 625 mg p.o. for
6 days in the hospital and 8 days upon discharge,
Metronidazol 3 × 500 mg p.o. for 6 days, Trilac
3 × 1 caps. as protection. A follow-up pantomography (Fig. 11) and radiography of the shank (Fig. 12)
were performed. On day 2 and day 5 her body temperature rose to 37.6°C in the afternoon. The sutures were removed after 14 days. The length of
Fig. 9. Operation – using a cancellous bone graft and
platelet-rich fibrin (PRF) to fill the bone defect
Ryc. 9. Zabieg chirurgiczny – wypełnienie ubytku
kostnego przeszczepem kości gąbczastej i fibryną bogatopłytkową PRF
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D. Ciapiński, I. Niedzielska, A. Witowski
Fig. 10. Operation – donor site after operation
Fig. 13. Follow-up pantomographic x-ray picture
2 months after operation
Ryc. 10. Zabieg chirurgiczny – miejsce dawcze po zabiegu
Ryc. 13. Zdjęcie RTG pantomograficzne kontrolne
2 miesiące po zabiegu chirurgicznym
Fig. 11. Follow-up pantomographic x-ray picture
2 days after operation
Ryc. 11. Zdjęcie RTG pantomograficzne kontrolne
2 dni po zabiegu chirurgicznym
Fig. 14. Follow-up pantomographic x-ray picture
6 months after operation
Ryc. 14. Zdjęcie RTG pantomograficzne kontrolne
6 miesięcy po zabiegu chirurgicznym
her hospital stay was 8 days. The patient was discharged on 4 October 2010. During the postoperative period she reported skin hypesthesia in her
right lower lip and in the region of right shank
tibial tubercle. She was given vit. B1 forte 3 × 1
tabl. daily. A pantomography was performed after 2 months (Fig. 13) and after 6 months (Fig. 14)
showing correct bone regeneration of the right
mandibular angle. Lower lip dysesthesia disappeared after 6 months, but she received biostimulating laser therapy for a slight skin hypesthesia in
her right shank (3 × 5 cm) which still persisted.
Fig. 12. Follow-up radiograph of the shank 2 days after
operation
Ryc. 12. Zdjęcie RTG podudzi kontrolne 2 dni po zabiegu chirurgicznym
Discussion
As bone tissue has limited regenerative abilities, large mandibular defects, if no augmentation
materials are used, take a long time to heal and often without full success [10]. Therefore, it is necessary to fill them with materials which have the
ability to activate all basic mechanisms that lead
Guided Regeneration of Bone Defects After Cystectomy
to bone reconstruction: osteoconduction, osteoinduction and osteogenesis. There are many reports
in the literature on materials and methods used
for this purpose [3–7, 10].
Cancellous bone, harvested from the proximal tibia, and platelet-rich fibrin (PRF), obtained
as a result of venous blood centrifugation, were in
sufficient volumes to fill a large defect after the removal of the cyst together with the two impacted
molars. Using autogenic grafts is the best method
to stimulate the reconstruction of bone tissue [11–
14]. An autogenic bone graft not only fulfils a supporting function but it stimulates reconstructive
processes on the recipient site due to its mother
cells, osteoblasts and quite a number of morphogenetic proteins.
Apart from its supporting function, a bone
graft plays a role as biological stimulator of osteogenesis. Each graft behaves in a similar way: it is
gradually resorbed to finally replace the recipient’s
own tissue.
Host’s cells cause resorption of the dead bone
tissue, thus leading to the release of factors inducing osteogenesis. A new bone tissue is created on the graft-resorbed surfaces. Gradually, the
graft will be completely replaced. The process of
bone graft reconstruction takes a long time, sometimes many months or even years [5]. In the case
of large bone defects, special attention should be
given to the proper choice of a donor site, as a sufficient volume of bone tissue has great significance
for the treatment.
Iliac ala and proximal tibial metaphysis seem
to be the cancellous bone donor sites of choice for
filling large defects after cystectomies. Other donor sites will give definitely smaller bone grafts.
Engelstad et al. [acc. 15] compared the volumes of
compressed cancellous bone harvested by means
of conventional surgical methods from three donor sites in fresh cadavers. The greatest volumes
were obtained from proximal tibia (11.3 mL) as
compared with posterior iliac crest (10.1 mL) or
anterior iliac crest (7.0 mL).
Many authors report that autogenic bone harvesting from the proximal tibial metaphysis is accompanied by definitely less complications as compared with the iliac ala. O’Keeffe et al. [14] noted
that the rate of complications after graft harvesting from the proximal tibial metaphysis was 1.3%.
Much higher rate of complications is connected
with harvesting from the iliac ala. Dimitriou et
257
al. [15] report that the rate of complications, infections, hematomas, fractures, hypertrophied scars)
in their group was over 19% with graft harvesting from the iliac bone as compared with 6% with
grafts from long bones.
Geideman et al. [16] observed only one complication in one patient (postoperative hematoma)
among a group of 155 patients in whom a cancellous
bone graft was harvested from the proximal tibia.
Bone graft harvesting from the iliac crest is often followed by persistent chronic donor site pain.
Sacco et al. [17] report that only 1% of their study
patients in whom a bone graft was harvested from
the iliac ala did not complain of donor site pain
on discharge. Their further observations were that
only 17% of patients did not complain of pain after 6 weeks and 43% of patients did not complain
of pain after 3 months.
On the other hand, donor site pain persisted in
41% of patients after 6 months, in 33% of patients
after 1 year and in 31% of patients after 2 years [17].
Owoola et al. [18] compared the bone donor sites:
proximal tibial metaphysis and iliac crest, based
on intraoperative evaluation (amount of the blood
loss, volume of the harvested graft, time needed for graft harvesting) and six-month follow-up.
Graft harvesting from the iliac crest took a much
longer time and involved a greater intraoperative
loss of blood and postoperative pain [18].
Platelet-rich fibrin (PRF), described for the
first time in 2001 by dr. Joseph Choukroun et al.
of Nice, is currently widely used in oral surgery
and maxillofacial surgery. In Dohan Choukroun
et al. [19–23] published a series of their studies describing PRF and its potential clinical applications.
When placed on the surfaces of autogenic bone
chips and inserted into a defect after cystectomy, PRF membranes not only function as a barrier separating the graft from the mucoperiosteal
flap but also stimulate correct the healing of the
postoperative wound as they contain a number of
growth factors that are gradually released.
PRF harvesting technique is relatively simple
and does not require any clotting factors, bovine
thrombin, calcium chloride or gelating factors.
PRF is solely a product of blood centrifugation.
Based on our first experience we believe that
using an autogenic cancellous bone, harvested
from the tibial tubercle, together with PRF membranes obtained from patient’s venous blood upon
centrifugation, is a very good solution.
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Address for correspondence:
Daniel Ciapiński
Department of Cranio-Maxillo-Facial and Oral Surgery
Medical University of Silesia
Francuska 20/24
40-027 Katowice
Poland
E-mail: [email protected]
Conflict of interest: None declared
Received: 20.03.2014
Revised: 30.03.2014
Accepted: 14.05.2014
Praca wpłynęła do Redakcji: 20.03.2014 r.
Po recenzji: 30.03.2014 r.
Zaakceptowano do druku: 14.05.2014 r.