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The aim of this study is to evaluate the efficacy of the application of allogenous bone at the maxillomandibular reconstructions for future rehabilitation with dental implants. The patients were submitted to reconstruction of maxilla, using allogeneic bone grafts, in 3 different techniques: onlay grafts for lateral ridge augmentation, onlay and particulate bone for sinus lift grafting, and particulate alone for sinus lift grafts. Clinical and radiographic control was done at the postoperative phase for at least 8 months, until the patient could be submitted to the installation of dental implants. The results showed success in the majority of the cases, and dental implants could be installed. This can be considered an excellent alternative when compared with the use of autogenous grafts; because handling is easier, there is a great amount of material available and a possibility of using local anesthesia, and consequently there is a reduction of patient morbidity.
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DENTAL IMPLANTS
J Oral Maxillofac Surg
66:2335-2338, 2008
Use of Allogeneic Bone Graft in Maxillary
Reconstruction for Installation of
Dental Implants
Kelston Ulbricht Gomes, DDS,* João Luiz Carlini, DDS, PhD,†
Cássia Biron, DDS,‡ Abrão Rapoport, MD, PhD,§ and
Rogério A. Dedivitis, MD, PhD
The aim of this study is to evaluate the efficacy of the application of allogenous bone at the maxillo-
mandibular reconstructions for future rehabilitation with dental implants. The patients were submitted
to reconstruction of maxilla, using allogeneic bone grafts, in 3 different techniques: onlay grafts for lateral
ridge augmentation, onlay and particulate bone for sinus lift grafting, and particulate alone for sinus lift
grafts. Clinical and radiographic control was done at the postoperative phase for at least 8 months, until
the patient could be submitted to the installation of dental implants. The results showed success in the
majority of the cases, and dental implants could be installed. This can be considered an excellent
alternative when compared with the use of autogenous grafts; because handling is easier, there is a great
amount of material available and a possibility of using local anesthesia, and consequently there is a
reduction of patient morbidity.
© 2008 American Association of Oral and Maxillofacial Surgeons
J Oral Maxillofac Surg 66:2335-2338, 2008
It is estimated that in the United States 40,000 persons
receive allogeneic grafts in the maxillomandibular re-
gion annually. Because of the development of special-
ized centers in the manipulation and processing of
skeletal tissues, the use of allogeneic grafts became an
alternative for the treatment of the atrophic maxilla
and mandible.
1
Osteogenesis is the most important basic principle
for total integration of bone grafts. The new bone
from the patient is produced by the osteoinduction
process, whereby mesenchymal cells differentiate
into osteoblast cells that produce new bone. This differ-
entiation process is coordinated by glycoproteins, such
as bone morphogenetic protein (BMP). BMPs are
present in both autogenous and allogeneic bone. The
process of osteoinduction determines the 3-dimensional
growth of capillary vessels, perivascular tissues, and os-
teoprogenitor cells from the patient to the graft.
2
The incorporation process of the graft happens
through the gradual replacement of bone until the
formation of new bone occurs, and this comprises 5
stages, beginning with the acute inflammatory pro-
cess, with gradual substitution by granulation tissue
and an increase in osteoclast activity.
2,3
The second and third stages are the incorporation
phase, which lasts several weeks and includes vascu-
*Postgraduation Student, Postgraduation Course on Health Sci-
ences, Heliopolis Hospital, São Paulo, and Maxillofacial Surgeon,
Center for Integral Assistance of Cleft Lip and Palate Patients,
Curitiba, Brazil.
†Professor, Maxillofacial Surgery Department, Federal University
of Paraná, and Head of Maxillofacial Surgery Service, Center for
Integral Assistance of Cleft Lip and Palate Patients, Curitiba, Brazil.
‡Maxillofacial Surgeon, Center for Integral Assistance of Cleft Lip
and Palate Patients, Curitiba, Brazil.
§Full Professor, Department of Surgery, University of São Paulo
Medicine School, and Coordinator, Postgraduation Course in
Health Sciences, Heliopolis Hospital, São Paulo, Brazil.
Postgraduation Course of Otorhinolaryngology and Head and
Neck Surgery, Federal University of São Paulo–Escola Paulista de
Medicina, and Professor, Postgraduation Course on Health Sci-
ences, Heliopolis Hospital, São Paulo, Brazil.
Address correspondence and reprint requests to Dr Gomes: De-
partment of Oral and Maxillofacial Surgery, Center for Integral Assis-
tance of Cleft Lip and Palate Patients, Rua Bruno Filgueira 369, Con-
junto 1402, CEP 80240-220 Bairro Batel, Curitiba, Paraná, Brazil;
e-mail: kelston_ulbricht@yahoo.com.br
©2008 American Association of Oral and Maxillofacial Surgeons
0278-2391/08/6611-0023$34.00/0
doi:10.1016/j.joms.2008.06.006
2335
larity and osteoinduction. During this phase, the im-
munologic system of the patient becomes sensitive to
the donor antigenicity, going through remodeling and
ending with an efficient structure. At this phase, the
medullary bone is totally reabsorbed and substituted,
and the cortical bone may remain even if partially
integrated.
2,3
The incorporation phase, characterized by osteoin-
duction and osteoconduction of allogeneic graft, is
slower than the same process when autogenous graft
is used, because of the immunologic response of the
patient. After 4 or 6 weeks, osteogenesis begins. After
1 year, the differences between allogeneic and autog-
enous grafts decrease.
2-4
The purpose of this study is to evaluate the appli-
cation of allogeneic bone for maxillary reconstruction
for future rehabilitation with dental implants.
Patients and Methods
We evaluated 28 patients who underwent allo-
graft surgery for maxillary reconstruction. The allo-
geneic bones used were obtained from the Bank of
Tissues and Bone of the Clinical Hospital of the
Federal University of Paraná, Brazil. The postoper-
ative follow-up ranged from 1 year to 6 years, with
implants and prostheses being functional through-
out the follow-up period.
The patients underwent reconstruction of maxilla,
by use of allogeneic bone grafts, via 3 different tech-
niques: onlay grafts for lateral ridge augmentation,
onlay and particulate bone for sinus lift grafting, and
particulate bone alone for sinus lift grafting (Fig 1).
GRAFT PREPARATION
Onlay Grafts
For onlay grafts, after the allogeneic bone had been
received from the Bank of Tissues and Bone, it was
manipulated with sterilized instruments. This phase
consists of preparation of the bone graft, usually har-
vested from a human femur, so that it fits the alveolar
defect. With the use of a reciprocating saw, the bone
was cut into block pieces (Fig 2); then it was safely
stored until it could be placed in the patient.
Particulate Grafts
For particulate bone grafts, the allogeneic bone was
cut into block pieces. Then, with the use of a specific
grinder instrument, the bone blocks were made into
particulate bone, and this was safely stored until it
could be used in the patient.
TECHNIQUES
Onlay Grafts for Lateral Ridge Augmentation
The first technique was used when there was suf-
ficient bone height to receive a dental implant but the
alveolar ridge was not wide enough.
The patient underwent local anesthesia in the area
of the procedure; then, with the use of a scalpel, an
incision was made so that a mucoperiosteal flap could
be released from the bone below. The recipient area
was prepared, and by use of round burs, perforations
were made to improve blood supply to the graft. The
block bone grafts, which had been prepared previ-
ously, were then adjusted to the recipient area and
fixated with 2 titanium screws, 1.5 mm in diameter, in
each block bone. Sharp areas from the grafts were
removed with round burs. Sutures were made with
FIGURE 2. Allogeneic bone.
Gomes et al. Allogeneic Bone and Maxillary Reconstruction.
J Oral Maxillofac Surg 2008.
FIGURE 1. Preoperative radiograph.
Gomes et al. Allogeneic Bone and Maxillary Reconstruction.
J Oral Maxillofac Surg 2008.
2336 ALLOGENEIC BONE AND MAXILLARY RECONSTRUCTION
Nylon No. 4 (Ethicon; Johnson & Johnson, Somerville,
NJ) and were kept in place for at least 14 days (Fig 3).
Onlay and Particulate Bone for Sinus
Lift Grafting
The second technique was used in the maxilla
when there was not enough height and width in the
area suggested to receive dental implants.
The patient received the same preparation with
local anesthesia. A mucoperiosteal flap was made, and
by use of a round bur, access to the maxillary sinus
was established. A specific instrument was used to
undermine and detach the sinus membrane so that it
could be lifted and allowed for loading with particu-
late bone, which had been prepared previously. This
procedure would recover the height of the area that
would receive the dental implants.
To promote the augmentation of the alveolar ridge,
especially at the anterior portion of the maxilla, the
bone blocks were used, in the same manner as de-
scribed previously.
The mucoperiosteal flap was released to cover the
surgical area without tension, by making relaxing in-
cisions and scoring the periosteum.
Particulate Bone Alone for Sinus Lift Grafting
The third technique was used every time there was
an intention to recover only the bone height at the
area that would receive the dental implants.
After preparation of the patient and allogeneic
bone as described previously, the maxillary sinuses
were filled with particulate bone at the area that
needed to recover its height.
A period of at least 8 months was planned before
the patient could be submitted to the installation of
dental implants.
Clinical and radiographic examination was done
during the postoperative phase.
Results
Eight cases of maxillary reconstruction, for lateral
ridge augmentation, were performed by use of onlay
grafts only. All cases were successful, and the dental
implants were installed (Table 1). In 7 cases, sinus
lifting with bone grafting was done, but dental im-
plants could only be installed in 5 patients. The other
2 patients underwent new reconstruction surgery. In
another 13 patients sinus lift bone grafting with allo-
geneic onlay and particulate bone grafts was done. It
was not possible to install dental implants in 2 cases.
Discussion
Some authors believe that the principal concern
regarding, and disadvantage of, allografts is risk of
infectious disease transmission, such as acquired im-
munodeficiency syndrome.
1-3
On the other hand, it is
FIGURE 3. Allogeneic bone grafts placed on the alveolar ridge of
the maxilla.
Gomes et al. Allogeneic Bone and Maxillary Reconstruction.
J Oral Maxillofac Surg 2008.
Table 1. TYPE OF GRAFT USED AND NUMBER OF SUCCESSFUL CASES
Graft
No. of
Cases Male Female
Success (Installation
of Dental Implants)
Shortest Time
of Follow-up
Longest Time
of Follow-up
Lateral ridge augmentation
with allogeneic onlay
grafts 8 3 5 8 1 yr 4 yr
Sinus lift bone grafts with
allogeneic particulate
bone grafts only 7 3 4 5 1 yr 6 yr
Sinus lift bone grafts with
allogeneic onlay grafts
and particulate bone
grafts 13 3 10 11 1 yr 5 yr
Total 28 6 19 24
Gomes et al. Allogeneic Bone and Maxillary Reconstruction. J Oral Maxillofac Surg 2008.
GOMES ET AL 2337
also stated that adequate material processing, includ-
ing freezing, demineralization, and lyophilization, can
decrease the risk of infection transmission.
4,5
Allograft has some advantages, such as easy manip-
ulation, great amount of material available, possibility
of local anesthesia for the procedure, cost reduction,
and morbidity reduction, because the use of another
donor site is not necessary.
2,6,7
When allograft is com-
pared with autogenous grafts, differences cannot be
observed at the final stage of incorporation with re-
gard to histology.
8,9
Research to evaluate the immunologic response,
performed in patients undergoing allograft surgery,
has shown no presence of antibodies in blood sam-
ples. Use of local anesthesia, the great amount of
material available, no need for a donor site, and cost
reduction are pointed to as the advantages of alloge-
neic grafts. However, the potential for infectious dis-
ease transmission is a disadvantage.
3
However, the
possibility of disease transmission with lyophilized
allograft and frozen cartilage was evaluated. Three
forms of virus were considered— human immunode-
ficiency virus, the viruses associated with Creutzfeldt-
Jakob disease, and the viruses associated with hepati-
tis B and C; up to 1993, no case had been found.
5
When allogeneic bone grafts are used for recon-
struction, the amount of time required for revascular-
ization is longer than that with reconstruction with
autogenous bone.
4
This is likely due in part to the
immunologic response. Fresh bone presents a better
immunologic response. Freezing and lyophilization
preserve properties to improve the chance of graft
incorporation.
4,10,11
On the basis of an analysis of the literature, as
described previously, many advantages of the use of
allogeneic grafts for maxillomandibular reconstruc-
tion can be listed, especially when it is compared
with the use of autogenous grafts. Handling is easier,
there is a great amount of material available, and there
is a possibility of using local anesthesia; consequently,
there is a reduction of patient morbidity. After all, it
was found in this study that in most of the patients,
dental implants could be installed, so the use of allo-
geneic bone graft can be considered a good alterna-
tive in this type of treatment.
References
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2. Mulliken JB, Glowacki J, Kaban LB, et al: Use of demineralized
allogeneic bone implants for the correction of maxillocranio-
facial deformities. Ann Surg 194:366, 1981
3. Köndell PA, Mattsson T, Astrand P: Immunological responses
to maxillary on-lay allogeneic bone grafts. Clin Oral Implants
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4. Perrott DH, Smith RA, Kaban LB: The use of fresh frozen
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fac Surg 51:1372, 1993
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7. Maletta JA, Gasser JA, Fonseca RJ, et al: Comparison of the
healing and revascularization of onlayed autologous and lyoph-
ilized allogeneic rib grafts to the edentulous maxilla. J Oral
Maxillofac Surg 41:487, 1983
8. Urist MR: Bone: Formation by autoinduction. Science 150:893,
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9. Urist MR: Bone morphogenetic protein induced bone for-
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tion, 1988
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erties of bone allografts. Clin Orthop Relat Res 54, 1983
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2338 ALLOGENEIC BONE AND MAXILLARY RECONSTRUCTION
... Indeed, the reported morbidity rate for the donor site is approximately 20% in all cases [10,11]. Furthermore, the amount of graft material is restricted, and sufficient amounts of autografts are often not available for massive grafts [12,13]. ...
... HR-MS: calc. EM + Na: 441.1520 g/mol; found: 441.1517 g/mol. 1 13 ...
... • C. HR-MS: calc. EM + Na: 233.0784 g/mol; found: 233.0718 g/mol. 1 13 In the last step of the synthesis for ArMA, photopolymerizable groups were attached. Therefore, MB5 (1.7 g, 8.1 mmol), MEHQ (1000 ppm), phenothiazine (300 ppm) and triethylamine (2.46 g, 24.3 mmol) were dissolved in dry THF (200 mL), cooled with an ice bath in a three-necked round bottomed flask and purged with argon. ...
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Wandering histiocytes, foreign body giant cells, and inflammatory connective-tissue cells are stimulated by degradation products of dead matrix to grow in and repopulate the area of an implant of decalcified bone. Histiocytes are more numerous than any other cell form and may transfer collagenolytic activity to the substrate to cause dissolution of the matrix. The process is followed immediately by new-bone formation by autoinduction in which both the inductor cells and the induced cells are derived from ingrowing cells of the host bed. The inductor cell is a descendant of a wandering histiocyte; the induced cell is a fixed histiocyte or perivascular young connective-tissue cell. Differentiation of the osteoprogenitor cell is elicited by local alterations in cell metabolic cycles that are as yet uncharacterized.
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The biomechanical properties of allograft bone can be altered by the methods chosen for its preservation and storage. These effects are minimal with deep-freezing or low-level radiation. Freeze-drying, however, markedly diminishes the torsional and bending strength of bone allografts but does not deleteriously affect the compressive or tensile strength. Irradiation of bone with more than 3.0 megarad or irradiation combined with freeze-drying appears to cause a significant reduction in breaking strength. These factors should be considered when choosing freeze-dried or irradiated allogeneic bone that will be subjected to significant loads following implantation.
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Two major problems in maxillocraniofacial surgery are the limited amount of fresh autogenous bone, the standard material for bone grafting, and the resorption of the grafted bone. Experimental studies with demineralized, devitalized bone matrix have shown induction of endochondral ossification. Fifty-five demineralized allogeneic implants have been used in 44 patients over the past two years for a variety of congenital (n = 37) and acquired (n = 7) defects. The allogeneic bone was obtained from cadavers, prepared as powders, chips or blocks, and was demineralized. After having been sterilized by irradiation, they were used to augment contour, fill defects, or construct bone within soft tissue. Of implanted sites that could be evaluated by physical examination, 31 of 31 were solid by three months. By radiographic examination three of 19 were healed by three months, and an additional 11 were positive by six months. Induced bone was seen in four of four biopsy specimens. Infection occurred in four of 44 patients (9%), comparable with conventional grafts. Implant resorption occurred in four instances. Allogeneic demineralized implants offer several advantages over conventional bone grafting, such as avoidance of a harvesting operation, ease of manipulation, and potentially unlimited material in banked form. In addition, healing by induced osteogenesis may bypass the resorption seen with healing of mineral-containing grafts.
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Oral and maxillofacial reconstructive surgeons using allogeneic tissues have expressed justifiable concern over the safety of these tissues as they relate to the transmission of infectious disease. This report reviews cases of infectious disease transmission from inadequately screened donors of allogeneic tissues, as well as those related to improper sterilization and cataloging of these tissues. It is concluded that good judgment and attention to good science on the part of the tissue bank as well as the surgeon can maximize the ability to place contamination-free specimens, thereby avoiding complications similar to those described.