1

Reconstruction of the Atrophic Edentulous Maxillas with Allograft Bone

(Fresh Frozen Bone) and Immediate Loading Implants

Celso Marques Oral and Maxillofacial Surgeon, Private Practice. Rua Artur de Azevedo, 1217 – cj 44 São Paulo, Brazil celso.marques@uol.com.br Luiz Fernando Akaki Borges Specialist in Prosthodontics Dentistry by Dental School of Ribeirão Preto - University of São Paulo Master in Oral Medicine by Heliópolis Hospital – São Paulo, Brasil Private Practice, São Paulo - Brazil Alexandre Augusto Benetton Oral and Maxillofacial Surgeon, Private Practice. Alberto Barlattani Specialist in Stomatology, Implants at University La Sapienza, Roma. Medical Director of University Tor Vergata Facultà of Dentistry, Roma. Responsible Professor, Catedra of Prosthodontics in Tor Vergata University, Roma. Samuel Porfirio Xavier MSci, DDS, PhD Department of Oral & Maxillofacial Surgery, University of São Paulo, Ribeirao Preto, Brazil. Suzie Aparecida de Lacerda Department of Morphology, Stomatology and Physiology, Dental School of Ribeirão Preto – USP Specialist in Oral Pathology by Dental School of Ribeirão Preto - University of São Paulo Master in Oral Rehabilitation by Dental School of Ribeirão Preto - University of São Paulo Doctor in Oral Rehabilitation by Dental School of Ribeirão Preto - University of São Paulo

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Reconstruction of the Atrophic Edentulous Maxillas with Allograft Bone

(Fresh Frozen Bone) and Immediate Loading Implants

Summary

Purpose: Assess the feasibility of reconstruction of the atrophic edentulous maxillas using

fresh frozen bone and their subsequent rehabilitation with immediate loading implants and

fixed prosthesis. Materials and Methods: Fourteen patients (average age 53.8) with severely

atrophic maxilla received fresh frozen bone grafts for width reconstruction (onlay block

grafts) and vertical augmentation of posterior regions (sinus augmentation) using particulate

bone and platelet-rich plasma). After an average of 6 month from the first surgical procedure,

the patients received 6 implants each with an immediate loading fixed prosthesis. Results:

Implant survival rate was 100% in the evaluation period (6 to 42 months) and no significant

complications occurred. Discussion: Histological evaluation of reconstructed atrophic

maxillas using fresh frozen bone grafts showed the presence of cellular nucleus in a

previously acellular tissue. This demonstrates the possibility of using the newly-formed bone,

confirming the feasibility of using this alternative material for grafting. The installation of

immediate loading osseointegrated implants 6 months after the graft has been shown to be

highly predictable and reliable. Radiographically, a normal bone aspect was noted in the sinus

areas that received bone grafts. The radiographs showed bone loss around the implants lower

than 0.5 mm after 42 months. Conclusions: The jaw bone reconstruction with fresh frozen

bone, and subsequent placement of immediate loading implants, and implant-supported fixed

prostheses was shown to be a viable and highly reliable alternative.

Key words: fresh frozen bone, bone grafts, reconstructive preprosthetic surgery,

augmentation, endosseous implants

3

Introduction

With the advent of osseointegrated implants, oral rehabilitation gained new

possibilities and perspectives. In the beginning, implants were installed in areas with

sufficient remaining bone. As time went by, several techniques were developed in order to

reconstruct atrophic areas, and subsequently install implants, for vertical (maxillary sinus

elevation, onlay bone graft, osteogenic distraction), or horizontal (onlay or particulate graft)

augmentation. Several materials were also used: autogenic, homogenic, xenogenic bone and

alloplastic materials.

The autogenic bone is considered the ideal standard and allows the comparison with

other techniques. However, the great inconvenience/difficulty is the morbidity produced by

another surgical site, frequently more painful than the receptor site. Hence, several researches

have been developed looking for a feasible substitute, with a reasonable cost, quality and

reliability similar to autogenic bone.

Conventional two-step dental implants have a high success rate. However, the time

period between implant installation and final prosthesis placement causes several damages.

For example, they may increase treatment time and the functional discomfort due to

temporary removable tissue-supported prostheses, especially for total edentulous patients.

Accordingly, research interest increased in shortening the time period between implant

placement and prosthetic rehabilitation. In recent years, several studies have demonstrated a

high success rate of early implant placement, with clinical application of immediate loading

implants, especially for the lower jaw(1,2). Recent publications also encourage early implant

placement for maxilla(3,4). However, patients with greatly reduced bone volume in the implant

receptor site need tissue augmentation. This can be obtained through the combination of

techniques for bone augmentation before the immediate loading implant placement(5).

4

Therefore, this paper presents a proposal for atrophic maxilla reconstruction using fresh

frozen allograft bone for width gains in the maxillary anterior region (onlay block) and

maxillary sinus elevation (particulate). After the graft maturation period (6 months), every

reconstructed maxilla received 6 strategically distributed implants that supported an

immediate loading implant-supported prosthesis. Fourteen cases were evaluated with clinical

and radiographic follow-up periods ranging from 6 to 44 months (average of 16.4 months).

5

Materials and Methods

The patients were submitted to a detailed anamnesis and the exclusion criteria were as

follows:

− Non-compensated systemic pathologies, such as diabetes and immune disorders;

− Recent history of chemotherapy for head and neck;

− Psychological disorders;

− Unavailability for return visits for long-term control;

− Remaining teeth with uncontrolled periodontal problems.

The patients were submitted to the following laboratory tests: hemogram,

coagulogram, glycemia test.

A computerized tomographic scan (CT) was requested to precisely measure the

remaining bone (Figures 1 and 2), as well as to create a prototype of a precise 3-dimensional

(3D) stereolithographic model (Figure 3). All patients presented with edentulous maxilla. The

CT scans showed the presence of an atrophic ridge of the remaining bone Class VI(6) that

hinders the placement of the appropriate implants, in terms of size and location, for prosthetic

rehabilitation.

The allogenic bone for the grafting was provided by the Skeletal Muscle Tissue Bank

of Hospital das Clínicas of Curitiba for 2 cases and by the Tissue Bank of the Orthopedics and

Traumatology Institute of the Hospital das Clínicas of São Paulo for 12 cases. This material

was harvested, processed, stored and distributed following the current standards for organ and

tissue transplantation. The patients were duly instructed and signed the patient informed

consent form for the procedures. The cases described used tibial bands.

6

The prototypes were sterilized in a 2% glutaraldehyde solution for 10 hours before the

surgery and were thoroughly washed with sterile physiological solution to be used in the

aseptic chain for adaptation of the graft.

The bone graft material for the transplant was received one hour before the beginning

of the surgery, in accordance with the protocol suggested by transplant regulatory bodies.

These require that, as the bone graft is taken from the tissue bank, where it is stored in ultra-

low temperature (lower than -80°C), it has to be transported in a special sealed thermal box,

packed and surrounded with dry ice, by a professional of the tissue bank, who must deliver it

checking the internal temperature of the package, that has to be below – 50° C (Figure 4).

After the surgical field was assembled, maintaining the aseptic chain, the bone blocks

were first adjusted on the prototypes in order to be well adapted(7) (Figures 5 and 6).

When the adjustment step was almost completed, the patient was anesthetized and the

incision was made medial to the alveolar ridge, from one tuber to the other, totally detaching

the flap and exposing the receptor beds. This medial shift of the incision aims at creating

better conditions for covering the graft, decreasing the tension of the suture (Figure 7).

Some accesses were made bilaterally to the maxillary sinus. The maxillary sinus

received particulate bone (Figures 8a and 8b), associated to platelet-rich plasma (PRP) (Figure

9), after the lateral wall opening and the sinusal membrane detachment, following the

conventional technique for augmentation of the maxillary sinus floor (Figure 10). In the

anterior regions, bone blocks fixed with 2 screws each were adapted (Figures 11 and 12). The

receptor cortical bone was perforated in some places with a round bur to facilitate the blood

supply and subsequent irrigation of the graft block. A 4.0 nylon thread was used for the suture

(Figure 13) and the patients were instructed not to wear dentures for 20 days. Mouthrinse with

0.12% chlorhexidine 3 times a day for 20 days was prescribed. After 7 days, the suture was

removed and the provisional prosthesis was readapted.

7

The drug protocol consisted of one tablet of azitromicine 500mg for 5 days and

dexametasone 4 mg every 12 hours for 3 days, in addition to analgesics depending on the

intensity of the pain.

Six months after the surgical grafting procedures, CT scans were made to evaluate the

results and to plan the implant placement (Figures 14a, 14b and 14c).

Before the surgery for implant placement, conventional impressions were taken for the

total prosthesis, wax rims were made and the teeth were mounted. After the evaluation of the

vertical dimension of occlusion and of the intermaxillary relation, multifunctional acrylic

surgical templates were fabricated (Figure 15), similar to the total prostheses, to guide the

implant positioning, and to transfer them to the working cast, in addition to record the

maxillomandibular relation for articulator mounting.

The placement of the implants was performed under local anesthesia. The incisions

were made on the alveolar ridge, the total flaps were detached, and the graft fixation screws

were removed (Figure 16). The multifunctional surgical templates, stored in a glutaraldehyde

solution, were thoroughly washed with 0.9% physiological solution and positioned. Six

BTLock System implants (3.75 mm diameter and 13 or 15 mm length; BTLock Vicenza,

Italy) were placed and strategically distributed, forming a polygon (Figure 17). The minimum

insertion torque was 32 N. The implant mounters slided easily into the surgical template

grooves. Vicryl type sutures were made without removing the implant mounters, which work

as impression copings (Figure 18). The surgical templates were filled with addition-type

silicone impression material (Monophase Stern Vantage; Sterngold Restorative Systems,

Germany) and placed in position. The prefabricated mounters were then fixed to the templates

with chemically curing resin (Pattern Resin-GC America Inc, Alsip, USA), using a procedure

similar to the one used for the impression of implants with an open-tray impression. It is

important that the mounters do not cause any occlusal interference, since a bite record with

8

acrylic resin is made at the end of the procedure in order to obtain a more precise adjustment

(Figure 19). The whole set was removed from the mouth and sent to the laboratory for

production of the immediate loading fixed prosthesis. Healing abutments were placed on the

implants (Figure 20).

After the working casts were prepared using replicas corresponding to the implants

installed, a cast-metal framework was produced by the prosthetic laboratory and the final

acrylization of the prosthesis was made over the framework (Figure 21).

One day after the implant placement, the fixed prostheses were installed making

meticulous occlusal adjustment (Figure 22). The patients were instructed to eat pasty

consistency food during 4 weeks and to use 0.12% chlorhexidine 3 times per day for 20 days.

They patients were clinically evaluated after 1, 4, 8 and 12 weeks, and then every 2

months. Radiographs were taken immediately after the prosthetic rehabilitation and

subsequently, every two months. These showed no inflammation or infection and a resorption

of less than 0.5 mm, indicating success for all the implants (Figure 23). Peri-implant probing

depths were demonstrated to be lower than 2 mm for all implants. The reestablishment and

maintenance of the facial aspect and no gingival inflammation were observed (Figure 24).

9

Results

Fourteen patients were treated, seven males and seven females, with ages ranging

from 35 and 67 years old (average age 53.8 years old). All patients presented with edentulous

maxilla associated to severe bone resorption, and were submitted to maxilla reconstruction

using fresh and frozen allograft bone. The anterior region received an onlay bone graft for

horizontal augmentation, and bilateral maxillary sinus augmentation was done with particulate

bone associated to PRP for vertical augmentation. All the cases progressed without any major

problem. The only complication faced was a small graft exposure presented in one case after

one week, which was corrected by resuturing the graft. After a six-month consolidation

period, the onlay bone graft fixation screws were removed from the respective areas, and

every patient received 6 implants. This was done in the areas approximately corresponding

and bilateral to the lateral incisors, the first pre-molars and the first molars, so as to form a

polygon. These implants received metalloplastic implant-supported fixed prosthesis

(Branemark protocol type) over a maximum period of 24 hours. After an observation period

of between 6 and 42 months (16.4 months in average), no implant was lost, the peri-implant

health was clinically and radiographically satisfactory in all cases, and the prostheses were

functioning normally, playing their role, without complaints from the patients. None of the

prosthesis was fabricated with cantilevers (Table 1).

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Discussion

There are many important factors to be considered in the rehabilitation of atrophic

maxillas, as, for example:

− Characteristics of alveolar ridge resorption, i.e., resorption rate, and whether the

resorption occurred in the height or width dimensions, as well as in the maxillary

sinus extensions;

− Maxillomandibular relation and vertical dimension of occlusion;

− Assessment of esthetic principles;

− Phonetic aspects of rehabilitation;

− Characteristics of the antagonist jaw: total prosthesis, removable or fixed partial

prosthesis;

− Systemic conditions of the patient.

Therefore, the alveolar ridge resorption rate, as well as its characteristics, will

determine the importance of the bone reconstruction to be performed, i.e., whether it will be

responsible for determining all esthetic and functional rehabilitation factors or whether the

prosthetic rehabilitation will share this responsibility. Thus, the prosthesis type will be of

utmost importance in the rehabilitation prognosis, i.e., in the case of fixed prosthesis, the

alveolar ridge responsibility is higher for reestablishing facial profile, since the prosthesis has

no gingival flange as in overdentures or hybrid prosthesis(8).

Reverse planning is vital for the oral rehabilitation success and the predictability of

results. For this reason, all patients were submitted to an analysis of the study models

mounted on semi-adjustable articulators, to determine the vertical dimension of occlusion and

the maxillomandibular relation. This phase is very important because it will determine the

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discrepancy between the residual alveolar ridge and the ideal tooth positioning of the final

prosthesis.

In this manner, we can evaluate the amount of bone graft necessary to recover the

alveolar ridge contour, further allowing not only the implant placement, but also the recovery

of the perioral muscle support, that is essential in the application of fixed prosthesis on

implants.

Autogenous bone grafting for maxilla reconstruction and subsequent implant

placement is a relatively common procedure with highly satisfying success rates in terms of

implant stability, efficacy of the prosthetic rehabilitation and patient satisfaction level(9, 10, 11).

The great inconvenience of this type of procedure is the obtention of the graft material.

Due to its autogenous source, it requires another surgical bed, increasing the morbidity and

complexity of the procedure. When the material need is small, there are some very common

intraoral areas that are options: mentum, oblique line, maxillary tuber, ascending branch of

the lower jaw. However, in cases needing more graft material we had to obtain extra-oral

material, generally harvested from the iliac crest or skullcap, which implies procedures

carried out in a hospital under general anesthesia, increasing morbidity and costs, and

discouraging patients and professionals to accept or to propose the treatment.

Trying to avoid this inconvenience, the search for a substitute for autogenous bone

yielded the homogenic material as an interesting alternative. After the bone tissue is

harvested, it must be submitted to several safety treatments, seeking to avoid disease

transmission and controlling imunogenicity, which include:

− Freeze drying (lyophilization);

− Ionizing radiation exposure;

− Ethylene oxide exposure;

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− Mechanical cleaning and ultra-low temperature freezing (-80ºC), to remove living

cells from the tissue that will be transplanted.

The freeze drying process (lyophilization) presents the advantage of sterilizing the

osseous tissue and making it easy to store. However, during these procedures there is a

significant loss of structural properties(12) with destruction of bone-inducing proteins(13). The

use of demineralized freeze dried bone (DFDB) allograft to recover atrophic areas is a

relatively common procedure, but with controversial results, as some authors obtained good

results(14) while others not so good(15).

The ionizing radiation exposure is effective to avoid the transmission of bacteria(16)

and to inactivate HIV in relatively low doses(17). However, grafted tissue loses desirable

biomechanical properties(18).

Irradiation was considered responsible for the poor results obtained in a study on

femoral homografts(19). The use of ethylene oxide preserves bone integrity, but it is important

to consider the toxic effects for the receptor(20).

The osseous tissue processing involving harvesting, mechanical cleaning and ultra-low

temperature freezing (-80ºC) produces the so called “Fresh Frozen Bone”. The low

temperature contributes to the preservation of the bone-inducing properties of osseous tissue,

and the maintenance of this biological property is very important for bone volume

recovery(21).

The risk of contamination with diseases like hepatitis B and C and AIDS in this type

of transplantation is minimal. In addition to the tests applied to all the samples donated, the

contamination rate of the donors tends to be lower than the rate observed in the population in

general(22).

13

The ultra-low temperature is thought to be able to rupture the cell membrane through

the crystallization of the water in the cells, makes the tissue bacteria free. The presence of live

cells in the fresh and cryopreserved bone samples was observed in the studies of Heyligers

and Klein-Nulend(23). Risk reduction for virus transmission and bacterial contamination with

this type of transplantation still depends on effective serum tests of the donor. In Brazil, the

Skeletal Muscle Tissue Banks follow the standards and procedures recommended by the

Sistema Nacional de Transplantes – SNT (Transplantation National System).

The prevalence of disease transmission through Fresh Frozen Bone transplantation is

low, considering the high number of procedures conducted today(24). A study with 138

patients who underwent arthroplasty of the hip using this type of transplantation showed

infection rates lower than 1% and these were proved not to be due to the transplanted

tissue(25).

Another factor to be considered when using Fresh Frozen Bone for transplantation is

the potential immune reaction, which includes transplanted tissue rejection. The ultra-low

temperature cryopreservation reduces graft immunogenicity(26). Therefore, there is no need to

submit receptors to immunosuppression, although the meaning and the incidence of the

immune response to this type of graft material are still not well established.

Some studies attempted to explain the risk factors of using bone grafts through the

analysis of human leukocyte antigen (HLA) in blood samples. The comparison of

pretransplant serum of 40 patients(27), followed by HLA analyses of samples after 3, 6, 9, 12,

18 and 24 months, revealed that sensitization occurred in 53% of the cases studied. No

evidence was found, however, linking this sensitization as a risk factor influencing the

incorporation of the bone graft. Another multicenter study(28) evaluated 84 patients

transplanted with fresh and frozen allograft bone. Serum samples for HLA analysis were

obtained before surgery, and during a follow-up period from 1 month to 4 years after surgery.

14

Sensitization before transplanting was shown in an average of 39% of the cases, probably due

to a positive history of blood transfusions and pregnancies. After grafting, there was an

increase in the average of sensitization cases from 39% to 67%, with evidence of the potential

immune sensitization. Notwithstanding, the link between this sensitization and grafting

success was not conclusive.

The use of fresh and frozen human bone is based on the selection of a material that

safely maintains as much as possible of the desirable properties, biological and

biomechanical, for maxillomandibular bone reconstruction.

The maintenance of the biological properties (still quantitatively uncertain) basically

refers to maintaining the bone-inducing potential of the bone graft. The death of the bone

matrix is believed to provide osteoblast-inducing factors and other essential proteins and/or an

osteoclast substrate for direct bone remodeling(29).

As to the maintenance of biomechanical properties, it is important to notice that the

peri-implant bone is frequently submitted to mechanical stress. Therefore, the formation of

bone with good density is desirable. Cryopreservation maintains the structural characteristics

of osseous tissue(30), and this is an important factor for the promotion of a proper osseous

conduction. Onlay block grafts lose their structural integrity when submitted to lyophilization

or irradiation(12, 18,30).

The fresh frozen bone discussed in this paper has been used for a long time in

orthopedics, but there is limited literature in oral and maxillofacial surgery(31).

In this study, all graft surgeries were carried out with platelet rich plasma placed

between the bone block and the receptor bed. This was done in the cases of onlay block graft,

as well as when added to the particulate bone used for maxillary sinus augmentation, in order

to accelerate new bone formation(32) and to facilitate the handling of the particulate

material(33).

15

It is possible to see the ossification on the histological study. These histological

sections were obtained at the time of implant placement and focus on the interface between

receptor bone and graft.

The sections examined reveal bone tissue composed of mature trabeculae with

osteocytes inside surrounded by medullary connective tissue, rich in blood vessels, fibers and

cells with normal histological appearance.

Images 25, 26 and 27 show the interface between the implanted bone tissue (left),

which is more compact and without osteocytes, and the bone formed after grafting (right).

Images 28 and 29 show the bone formed after grafting in more detail.

Today, immediate or early prosthetic rehabilitation on implants for edentulous

maxillas is a predictable and reliable procedure(4,34). In addition, the possibility of using

osseointegrated implants for reconstructed maxillas through bone grafting is well

demonstrated(10,11,35,36) and represents today a relatively common treatment alternative.

In this study, at the time of the graft reopening and placement of the implants, the

bone appeared to be of excellent quality. This property provided good initial stability, with

insertion torque higher than 32N, sufficient to indicate immediate loading(3,37). A discrete

bone resorption was observed, probably due to the graft being cortical.

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Conclusions

Reconstruction of atrophic maxillas using Fresh Frozen Bone presented encouraging

results with preservation terms of up to 42 months. In addition, immediate loading on

edentulous maxillas is viable as long as there is quality bone structure in a sufficient amount

to enable good distribution and primary stability of the implants. However, this is still a

fruitful field for further research.

17

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14. Simion M, Jovanovic SA, Trisi P, Scarano A, Piattelli A. Vertical ridge augmentation around dental implants using a membrane technique and autogenous bone or allografts in humans. Int J Periodont Rest Dent 1998;18:9-23.

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23. Heyligers IC, Klein-Nulend J. Detection of living cells in non-processed but deep-frozen bone. Cell Tissue Bank 2005; 6(1):25-31.

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28. Strong DM, Friedlander GE, Tomford WW, Springfield DS, Shives TC, Burchardt H. et al. Immunologic responses in human recipients of osseous and osteochondral allografts. Clin Orthop 1996;326:107-14.

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30. Hamer AJ, Strachan M, Black M, Ibbotson CJ, Stockey I, Elson RA. Biomechanical properties of cortical allograft bone using a new method of bone strength measurement: A comparison of fresh, fresh-frozen and irradiated bone. J Bone Joint Surg Br 1996;78-B:363-8.

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32. Gerard D, Carlson ER, Gotcher JE, Jacobs M. Healing of autologous bone grafted mandibular defects in dogs J Oral Maxillofac Surg 2006;64:443-51.

33. Froum SJ, Wallace SS, Tarnow DP, Cho SC. Effect of Platelet-Rich Plasma on Bone Growth and Osseointegration in Human Maxillary Sinus Grafts: Three Bilateral Case Reports. Int J Periodontics Restorative Dent 2002;22:45-53.

34. Jaffin RA, Kumar A, Berman CL. Immediate loading of dental implants in the completely edentolous maxilla: A clinical report. Int J Oral Maxillofac Implants 2004;19:721-30.

35. Cheung LK, Leung ACF. Dental Implants in Reconstructed Jaws: Implant Longevity and Peri-Implant Tissue Outcomes. J Oral Maxillofac Surg 2003;61:1263-74.

36. Gerry M, Raghoebar PS, Henny JA, Meijer KS, Arjan V. Early loading of endosseous implants in the augmented maxilla: a 1-year prospective study. Clin Oral Impl Res 2003;14:697-702.

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Table 1 - Patients treated, period in use and complications found

Patient Age Sex Period in use (months)

Intercurrences

LPF 44 F 44 No AML 40 F 27 No NN 44 M 21 No DF 61 M 20 Graft exposure AP 52 F 18 No MAM 65 F 18 No SPS 54 F 14 No VGM 65 M 12 No WTP 45 F 12 No KT 64 M 12 No NPF 67 F 11 No AGA 52 M 9 No GV 48 M 6 No

ERP 53 M 6 No

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Legends of the illustrations

Figure 1 – Computerized tomographic scan – Axial slice before grafting

Figure 2 – Computerized tomographic scan – 3-dimensional reconstruction before grafting

Figure 3 – Prototype before grafting

Figure 4 – Band-form tibial fresh frozen bone

Figure 5 – Verification of bone adaptation on prototype

Figure 6 – Adjustments for bone adaptation on prototype

Figure 7 – Occlusal view after incision and mucoperiosteal detachment

Figure 8 a – Utilization of bone mill

Figure 8b – Particulate bone

Figure 9 – Particulate bone associated to autogenous platelet-rich plasma

Figure 10 – Access window to maxillary sinus filled with particulate bone

Figure 11 – Adaptation of bone blocks to the receptor bed

Figure 12 – Fixation of bone blocks to the receptor bed

Figure 13 – Occlusal view of the suture

Figure 14 a – Computerized tomographic scan – Axial slice 6 months after grafting

Figure 14 b – Computerized tomographic scan – 3-dimensional reconstruction 6 months after grafting

Figure 14 c – Prototype after grafting

Figure 15 – Multifunctional surgical template

Figure 16 – Front view after incision and detachment for the implant placement surgery

Figure 17 – Multifunctional template with implants placed in position

Figure 18 – Impression copings in position

Figure 19 – Impression with multifunctional template in position and splinted impression copings

Figure 20 – Healing abutments in position (24 hours after surgery)

Figure 21 – Acrylized prosthesis

Figure 22 – Prosthesis in place

Figure 23 – Radiographic image 12 months after prosthesis installation

Figure 24 – Front view of prosthesis in function

Images 25, 26 and 27 show the interface between the implanted bone tissue (left), which is more compact and without osteocytes, and the bone formed after grafting (right).

Images 28 and 29 show the bone formed after grafting in more detail.

22

Ilustrations

Figure 1

Figure 2

23

Figure 3

Figure 4

24

Figure 5

Figure 6

25

Figure 7

Figure 8 a

26

Figure 8b

Figure 9

27

Figure 10

Figure 11

28

Figure 12

Figure 13

29

Figure 14 a

Figure 14 b

30

Figure 14 c

Figure 15

31

Figure 16

Figure 17

32

Figure 18

Figure 19

33

Figure 20

Figure 21

34

Figure 22

Figure 23

35

Figure 24

36

Figure 25 – (50X)

Figure 26 – (100X)

37

Figure 27 – (100X)

Figure 28 – (50X)

38

Figure 29 – (100X)