Journal of Oral Implantology Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible Augmentation --Manuscript Draft-Manuscript Number:
aaid-joi-D-16-00095R1
Full Title:
Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible Augmentation
Short Title:
Stability of Fresh Frozen Bone Blocks in Mandible
Article Type:
Clinical Research
Keywords:
Fresh frozen bone allograft, atrophic mandible, histological analysis, tomographic analysis, dental implants.
Corresponding Author:
Erick Silva, PhD student School of Dentistry of Ribeirão Preto, University of São Paulo Ribeirão Preto, São Paulo BRAZIL
Corresponding Author Secondary Information: Corresponding Author's Institution:
School of Dentistry of Ribeirão Preto, University of São Paulo
Corresponding Author's Secondary Institution: First Author:
Erick Silva, PhD student
First Author Secondary Information: Order of Authors:
Erick Silva, PhD student Emanuela Prado Ferraz, PhD student Evandro Carneiro Martins Neto, PhD student Liat Chaushu, Resident Gavriel Chaushu, Associate Professor Samuel Porfirio Xavier, Associate Professor
Order of Authors Secondary Information: Abstract:
The aim of this prospective controlled study present study is to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using FFB. Twenty consecutive patients presenting for reconstruction of posterior mandibular alveolar bone ridge width ≤ 6.0 mm and/or height≤ 6.0 who met all inclusion and exlusion criteria were included. FFB blocks were used. The main outcome variable investigated was bone volume dynamics. Vertical, horizontal and three-dimensional bone gain data was measured from computerized tomography scans. The main predictor variable was time evaluated at three points: immediately after surgery (T1), at implant placement (T2) and 01 year after functional loading (T3). Secondary outcome parameters evaluated were implant survival, histological findings and microtomographic morphometry. Twenty-eight hemi-mandibles, 50 FFB bone blocks, 15 females and 5 male patients (mean age - 51.8 years). Block and implants survival rate were respectively 100% and 96% after 31.75 months of follow up. Vertical and horizontal bone gain at T2 was 5.15 and 6.42 mm respectively. Volumetric resorption was 31% at T2, followed by an additional 10% reduction at T3. Histological evaluation showed newly formed vital bone in intimate contact to the remaining FFB. Microtomography revealed 31.8% newly formed bone, 14.5% remaining grafted bone and 53.7% connective tissue and bone marrow. Thus, FFB blocks may lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implant-supported rehabilitation with high success rates.
Response to Reviewers:
Dear Mr. Jim Rutkowski, DMD, PhD Editor-in-Chief
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Journal of Oral Implantology We appreciate the reviewer’s comments (reviewer #2). All suggestions were well received by the authors. We also agree that the article will become more atractive and beneficial to JOI readers with the corrections. The modifications were highlighted in text. Please find bellow the suggested corrections: 1)Line 8. FFB. Please explain acronym. ANSWER: acronym was explained in the second line of the abstract (Page 1, line). 2)Abstract: bacterial or viral transmission of fresh frozen bone have to be discussed. ANSWER: We included a paragraph for bacterial/virus transmission discussion (Page 1, lines 1-3). Material and Methods: 3)explain the use of Mimics software. How the measurements were made? Who made the measurements? When Mimics software is used the measurements are operator dependent. ANSWER: In the section “Tomography”, we performed a fully detailed description of how all the measurements were made (see Page 6, lines 11-23). Four references were cited for better understanding of the methodology and also for complementary information. 4)was a CT scan performed preoperatively? ANSWER: Yes, a CT scan was performed preoperatively only for surgical planning. This CT scan was not used for measurements. We included a sentence to explain the finality of this scan (Page 6, lines 4-7). 5)Which is the origin of the fresh frozen bone? A tissue bank? ANSWER: Yes, all the bone blocks were obtained from a musculoskeletal tissue bank called UNIOSS (Marília, Brazil). This missing information was included in the text in the section “Study Design” (see Page 4, lines 21 and 22). 6)Description of surgery? FFB blocks fixation? Flap management? ANSWER: The description of surgical procedure was included in the section “Study Design” (see Page 5-6, lines 23-19). 7)Line 22. 8%+40%+44%=92% ???????? ANSWER: Sorry. Data was mistyped. The correct is as follows: “Eight percent of the grafts were used to gain height, 48% were used to gain width, and 44% to gain both height and width.” (see Page 8, lines 5-6). 8)Dental implants factory and characteristics? ANSWER: Please see Page 5, lines 16 and 17. This article is based on a clinical case series in order to evaluate grafting technique and its volumetric behaviour. We have previously published histological and clinical results in Clin Oral Implant Research - 2015 (Dias et al.). We believe that all the requests were fulfilled. Kind Regards, Erick Ricardo Silva, DDS, OMFS, MsC, PhD Student Department of Oral and Maxillofacial Surgery and Periodontology School of Dentistry of Ribeirão Preto – USP E-mail: [email protected]
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Article File
Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Augmentation Volumetric Stability of Fresh Frozen Bone Blocks in Mandible
Erick Ricardo Silva, DDS* Emanuela Prado Ferraz, DDS, MSc* Evandro Carneiro Martins Neto, DDS, PhD* Gavriel Chaushu, DMD, MSc** Liat Chaushu, DMD, MSc† Samuel Porfírio Xavier, DDS, PhD‡
* PhD student, Department of Oral and Maxillofacial Surgery and Periodontology, The School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. ** Associate Professor, Department of Oral and Maxillofacial Surgery, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel. †
Resident, Department of Periodontology, The Maurice and Gabriela Goldschleger
School of Dental Medicine, Tel Aviv University, Israel. ‡
Assistant Professor, Department of Oral and Maxillofacial Surgery and Periodontology,
The School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. Corresponding author:
Erick Ricardo Silva 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
PhD student, Department of Oral and Maxillofacial Surgery and Periodontology, Ribeirão Preto Dental School, University of São Paulo, Brazil. Tel: +55 16 3315 4053 e-mail: [email protected]
CONFLICT OF INTEREST Conflict of Interest and Source of Funding Statement: The authors declare that they have no conflict of interest related to this study.
ACKNOWLEDGEMENTS The authors would like to thank Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) for financial support. Sebastião Carlos Bianco and Adriana Luisa Gonçalves Almeida are acknowledged for technical assistance.
ABSTRACT Fresh frozen bone allografts (FFB) has become an alternative for bone augmentation in the last decades, especially because the absence of recent reports of disease transmission or immunologic reactions when it is used. The aim of this prospective controlled study present study is to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using. Twenty consecutive patients
presenting for reconstruction of posterior mandibular alveolar bone ridge width ≤ 6.0 mm 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
and/or height≤ 6.0 who met all inclusion and exlusion criteria were included. FFB blocks were used. The main outcome variable investigated was bone volume dynamics. Vertical, horizontal and three-dimensional bone gain data was measured from computerized tomography scans. The main predictor variable was time evaluated at three points: immediately after surgery (T1), at implant placement (T2) and 01 year after functional loading (T3). Secondary outcome parameters evaluated were implant survival, histological findings and microtomographic morphometry. Twenty-eight hemimandibles, 50 FFB bone blocks, 15 females and 5 male patients (mean age - 51.8 years). Block and implants survival rate were respectively 100% and 96% after 31.75 months of follow up. Vertical and horizontal bone gain at T2 was 5.15 and 6.42 mm respectively. Volumetric resorption was 31% at T2, followed by an additional 10% reduction at T3. Histological evaluation showed newly formed vital bone in intimate contact to the remaining FFB. Microtomography revealed 31.8% newly formed bone, 14.5% remaining grafted bone and 53.7% connective tissue and bone marrow. Thus, FFB blocks may lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implant-supported rehabilitation with high success rates. KEY WORDS: fresh frozen bone allograft, atrophic mandible, histological analysis, tomographic analysis, dental implants.
INTRODUCTION
The increasing predictability of modern dental implants has created an opportunity 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
for their installation in compromised sites.1 However, the presence of an adequate bone volume is necessary to allow correct implant positioning and provide long-term stable biomechanical results.2, 3 Therefore, implants should be placed in accordance both to prosthetic planning and bone availability.4, 5 Several surgical procedures for bone augmentation are currently being used. Autogenous bone graft, harvested from either intra6 or extraoral7 donor sites, is considered the gold standard8, 9 due its osteoconductive, osteoinductive and osteogenic properties.10 However, the use of autogenous bone might result in donor site morbidity as postsurgical pain, paresthesia and increased operative time and costs.11-16 Furthermore, graft resorption rates of up to 30% have been reported at the first year.17, 18 However, it has been suggested that the addition of bone bovine mineral to the graft surface reduces resorption.19, 20 In the past few years, fresh frozen bone allograft (FFB) has become an interesting alternative to overcome the disadvantages of autogenous bone.21, 22 The use of FFB has been widely reported for a variety of clinical situations as sinus augmentation23, 24 and onlay graft.25-27 The development of strict guidelines of tissue harvesting, processing, storing and record-keeping, considerably decreased the risk of primary infection and antigenicity.28-30 Nevertheless, only a few studies assessed the use of FFB in the posterior mandible.25, 27, 31 The purpose of the present study was to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using FFB. The null hypothesis was that newly created bone will undergo dimensional changes time. The specific aims of the study are to measure: 1. linear (width and height) and 2.
Three-dimensional bone changes at three time points: immediately after bone grafting 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
(T1), six months postoperatively at implant placement (T2) and 1 year after functional loading (T3). Clinical results were assessed at T2 and T3, microtomographic and histological findings at T2. MATERIALS AND METHODS Study design Prospective controlled study. This study protocol was approved by the Ethical Committee for Human Studies (Committee CAAE: 01473512.4.0000.5419) School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. Twenty consecutive patients with posterior mandibular residual alveolar bone ridge width ≤ 6.0 mm and/or height≤ 6.0 were included in this study. Inclusion criteria were age ≥ 18 years old, good general and mental health, nonsmoking, good oral health and dental conditions with no active periodontal disease or occlusal problems. Exclusion criteria were compromised oral and/or general health (ASA III and IV patients), pregnancy, smoking, acute or chronic alcohol abuse, radiotherapy, and use of bisphosphonates. All surgeries were performed by the same experienced surgeon, according to the technique described by Dias et al. 201425. Patients were instructed to maintain strict oral hygiene in the two week that preceded both grafting and implant placement surgical procedures. Prophylactic amoxicilin (1g) was prescribed in all cases. For the grafting surgery, corticocancellous bone blocks from a musculoskeletal tissue bank (UNIOSS, Marilia, Brazil) were obtained from distal femoral epiphysis with approximate dimensions of 20 x 10 x 6 mm. Under local anestesia (2% mepivacaine with 1:100.000 epinephrine), a full thickness flap was performed for gaining acess to the alveolar ridge bone defect. In order to improve vascular graft nutrition, the native bed bone was
perforated on its cortical buccal aspect. FFB bone blocks were sculped and shaped 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
tridimensionally according to the bone defect using diamond burs and a micro saw. After passive adaptation of the shaped block over the alveolar defect, it was fixed in the proper position with 1.5 x 10 mm titanium screws (Synthes, Oberdorf, Switzerland). All blocks were perforated on the cortical aspect. The cortical sharp edges of the graft were removed with the same diamond burs and BBM 0.25-1.0 mm granules (Bio-Oss, Geistlich Pharma, Basel, Switzerland) were used to cover the block and proximal areas. The surgical site was completely covered with a resorbable collagenous membrane (Bio-Gide, Geistlich Pharma, Basel, Switzerland) before wound closuring (see Figure 1, A – F). Tension-free closure and passive sutures were achieved through internal periosteal release of the buccal flap and partial detachment of mylohyod muscle. The grafts healing time was 6 months. None of the patients were allowed to used any kind of prosthetic device during this period. At six months after grafting, a single biopsy was collected from each patient for histological analysis from the middle of the graft. In the same surgical procedure, conventional cone morse implants were installed (TitamaxCM Cortical, Neodent, Curitiba, Brazil). Six months after implant installation, the patients were rehabilitated prosthetically with cemented implanted-supported single tooth restorations and followed for 1 year after functional loading
Tomography 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Cone beam computerized tomography (CBCT) scans were taken immediately after the grafting surgery (T1), six months postoperatively at implant placement (T2) and 1 year after functional loading (T3). A CBCT scan was also performed before grafting procedure for surgical planning purpose, such as to investigate bone atrophy and inferior alveolar bundle position. This CBCT was not used for linear and volumetric measurements. The CBCT model iCat Classic (Imaging Science International, Hatfield, EUA) with exposure factors of 120 kV and 36.12 mAs with 0.25 mm reconstruction interval and slice thickness was used. The DICOM files were processed by Mimics version 8.13 (Materialise, Leuven, Belgium) to asses linear and volumetric changes at the different times of the study (see Figure 2). For linear measurements, fixation screws heads were used as reference points. The values found between the crest of residual alveolar rigde and the superior and lateral border of the the graft were used for evaluation of height and thickness, respectively. To determine the volume of the grafts, the area of the graft in all of the CT slices was measured. All measurements were performed on sagittal slices (cross-sections). The contour of the graft was manually traced on each CT slice. The contrast/exposure of the images was adjusted for better assessment of the delineation of structures. The graft area was calculated automatically with Mimics software. The graft volume was also automatically calculated, corresponding to the sum of all sagittal areas slices. This methodology has been widely used and this measurement protocol has become the most acceptable for bone graft evaluation32-34. An expertise technician performed both linear and volumetric measurements.
MicroCT
Bone biopsies were taken during implant surgery. Samples were passively 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
removed from the trephines and kept in 10% buffered formalin at pH 7.4 for 48 h and transferred to a solution of 70% ethanol for 72 hours. Micro-CT analysis was performed using the SkyScan 1172 system (Bruker-SkyScan, Kontich, Belgium). Morphometric analysis was used to quantify the percentage of the histological elements. Histology After micro-CT analyses, samples were submitted to histological assessment using hematoxilin and eosin (H&E) staining, according to Xavier et al. 201524. Histological evaluation aims to assess the presence/absence of newly formed vital bone, remaining grafted bone and connective tissue in the specimens. Statistical Analysis For statistical analyses, first a Shapiro-Wilk normality test showed a non-normal distribution of the data, which were expressed as mean ± standard deviation (SD). Statistical significance was determined by one way analysis of variance and the MannWhitney U test. The Tukey multiple comparison posttest was also used to isolate the group per groups that differed from the others. Both graft and implant survival were estimated using Kaplan-Meirer survival curves. The SigmaPlot version 11 software (Systat Software, Witzenhausen, Germany) was used for all analyses. A value of p < 0.05 was considered statistically significant. RESULTS Clinical Outcomes Table 1 summarizes the demographic data. A total of 20 patients (15 females and 5 males) with a mean age of 51.8 ± 7.5 years (ranging from 37 to 64) were included in
the study. Twenty eight hemi-mandibles were reconstructed with 50 FFB bone blocks. 32 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
blocks were used for molar region and 18 were used for pre-molar region. Eight percent of the grafts were used to gain height, 48% were used to gain width, and 44% to gain both height and width. All surgeries were well tolerated by the patients. No bone block was lost. Small expositions of the graft were observed between 15 and 45 postoperative days in 6 patients, and all of them were treated with 2% Chlorhexidine gel until spontaneous closure occurred within 10 days. Tomography Vertical bone gain at T1 was 5.15 ± 1.04 mm decreasing (24%) to 3.91 ± 0.94 mm at T2 = and additional 25% to 2.92 ± 0.71 mm at T3 (see Figure 3). Horizontal bone gain was 6.42 ± 1.20 mm at T1, decreasing (28%) to 4.64 ± 1.32 mm at T2 and additional 13% to 4.02 ± 0.71 mm at T3 (see Figure 4). Bone gain in horizontal dimension showed a tendency to exceed bone gain in vertical dimension over the entire evaluation period, although it was not statistically different (eg, ANOVA, p > 0.05). Volumetric bone gain was: T1 = 1176.62 ± 358.08 mm³; T2 = 785.78 ± 201.16 mm³ and T3 = 689.72 ± 187.45 mm³ (see Figure 5). Thus, general volumetric bone resorption of 31 ± 15% at T2, followed by an additional 10 ± 14% reduction was noted at T3 (see Figure 6). Six months after the grafting procedures (T2), 50 implants were installed with a torque of insertion of 46 ± 4.9 N/cm. Implant length ranged from 9.0 mm to 11.0 mm. Implant diameter was similar (3.75 mm). The implant survival rate was 96% after 31.8 ± 7 (ranging from 20 to 42) months of follow up. Two implants failed at second stage surgery. The clinical view of the bone around the implants was healthy and the reason for failure was probably lack of osseointegration.
MicroCT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Micro-CT images showed an intimate contact between newly formed bone and remaining grafted bone in all samples, resembling the histological findings (see Figure 7). Micro-CT morphometric analysis revealed newly formed bone = 31.8 ± 0.5%; remaining grafted bone = 14.5 ± 0.2%; connective tissue and bone marrow = 53.7 ± 0.5%. Histology The histological analysis revealed newly formed vital bone, remaining grafted bone and connective tissue in all specimens. Empty osteocyte lacunae were used for identification of the remaining grafted bone. Newly formed vital bone with viable osteocyte was found in intimate contact with remaining grafted bone. Osteoblasts were seen at the margins of the calcified regions. Blood vessels within the connective tissue were also found. No evidence of acute or chronic inflammation infiltrate was observed (see Figure 8).
DISCUSSION This study was designed to evaluate the dimensional changes of new gained bone following augmentation of atrophic posterior mandibles with corticocancellous FFB blocks. The grafting procedures enabled the adequate reconstruction of alveolar ridges for further implant placement. A similar grafting technique has been previously reported by Nissan et al.31 However, in the present study cortico-cancellous FFB blocks were used instead of cancellous freeze-dried bone allograft (FDBA) blocks. Corticocancellous bone blocks present a thin external cortical layer allowing easier locking of fixations screws and numerous internal cancellous sites for increasing graft perfusion.34-36 Furthermore,
FFB blocks were covered with BBM and a collagenous membrane once to assist in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
volumetric maintenance of the new gained bone.20, 25,37,38 It has been suggested that mandibular grafting is less predictable than grafting in the maxila.39 In this study, there were no complications related to the graft incorporation process, as graft block detachment of the recipient bone bed. All of the blocks were fully attached to the recipient sites during the entire time points (survival rate = 100%). This is compatible compared to previous reports.32, 40 In the present study, bone gain in vertical dimension and horizontal dimension resembled values reported by Nissan and colleagues.32 The new gained bone allowed adequate implant placement. All the implants showed proper primary stability (insertion torque = 46 ± 5N/cm). Only two out of fifty implants failed and had to be replaced (implant survival rate = 96%). These results of the present study are consistent with previously published data.25, 27, 31, 41 For any kind of graft, a major drawback is the volume reduction that occur with the time1. Most of the available studies evaluating the dimensional changes of the grafts have drawbacks.42-44 One of the limitations is the performance of the linear measurements. Linear measurement techniques depend on a reference point and they can easily under-or overestimate the results. Bone dynamics occurs in a non-uniform volumetric pattern.1 For this reason, three dimensional measurements are more accurate. It can be speculated that implant placement at T2 contributed to the decrease in the resorption rate of the new gained bone between T2 and T3.45 The microtomographic and histological analysis of the grafts after a follow up period of 6 months showed newly formed vital bone in contact to the remaining bone grafted. In this study, the morphometric findings were similar to those reported by Nissan
et al.27, Dias et al.25 and Spin-Neto and colleagues.46 The residual grafted bone did not 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
influence the implant osseointegration outcome, as demonstrated by the results. CONCLUSION Within the limits of the present study, FFB blocks lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implantsupported rehabilitation with high success rates.
REFERENCES 1.
Deluiz D, Oliveira LS, Pires FR, Tinoco EM. Time-dependent changes in fresh-
frozen bone block grafts: tomographic, histologic, and histomorphometric findings. Clin Implant Dent Relat Res 2015; 17: 296-306.
2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Ishikawa T, Salama M, Funato A, Kitajima H, Moroi H, Salama H, Garber D.
Three-dimensional bone and soft tissue requirements for optimizing esthetic results in compromised cases with multiple implants. Int J Periodontics Restorative Dent 2010; 30: 503-511. 3.
Bidra AS, Chapokas AR. Treatment planning challenges in the maxillary anterior
region consequent to severe loss of buccal bone. J Esthet Restor Dent 2011; 23: 354-360. 4.
Bidra AS. Surgical and prosthodontic consequences of inadequate treatment
planning for fixed implant-supported prosthesis in the edentulous mandible. J Oral Maxillofac Surg 2010; 68: 2528-2536. 5.
McAllister BS, Haghighat K. Bone augmentation techniques. J Periodontol 2007;
78: 377-396. 6.
Nowzari H, Aalam AA. Mandibular cortical bone graft part 2: surgical technique,
applications, and morbidity. Compend Contin Educ Dent 2007; 28: 274-280; quiz 281272. 7.
Donovan MG, Dickerson NC, Hanson LJ, Gustafson RB. Maxillary and
mandibular reconstruction using calvarial bone grafts and Branemark implants: a preliminary report. J Oral Maxillofac Surg 1994; 52: 588-594. 8.
Khan SN, Cammisa FP, Jr., Sandhu HS, Diwan AD, Girardi FP, Lane JM. The
biology of bone grafting. J Am Acad Orthop Surg 2005; 13: 77-86. 9.
Sajid MA, Warraich RA, Abid H, Ehsan-ul-Haq M, Shah KL, Khan Z.
Reconstruction of mandibular defects with autogenous bone grafts: a review of 30 cases. J Ayub Med Coll Abbottabad 2011; 23: 82-85. 10. 294.
Hoexter DL. Bone regeneration graft materials. J Oral Implantol 2002; 28: 290-
11. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Nkenke E, Radespiel-Troger M, Wiltfang J, Schultze-Mosgau S, Winkler G,
Neukam FW. Morbidity of harvesting of retromolar bone grafts: a prospective study. Clin Oral Implants Res 2002; 13: 514-521. 12.
Clavero J, Lundgren S. Ramus or chin grafts for maxillary sinus inlay and local
onlay augmentation: comparison of donor site morbidity and complications. Clin Implant Dent Relat Res 2003; 5: 154-160. 13.
Joshi A. An investigation of post-operative morbidity following chin graft
surgery. Br Dent J 2004; 196: 215-218; discussion 211. 14.
Joshi A, Kostakis GC. An investigation of post-operative morbidity following
iliac crest graft harvesting. Br Dent J 2004; 196: 167-171; discussion 155. 15.
von Arx T, Hafliger J, Chappuis V. Neurosensory disturbances following bone
harvesting in the symphysis: a prospective clinical study. Clin Oral Implants Res 2005; 16: 432-439. 16.
Silva FM, Cortez AL, Moreira RW, Mazzonetto R. Complications of intraoral
donor site for bone grafting prior to implant placement. Implant Dent 2006; 15: 420-426. 17.
van der Meij AJ, Baart JA, Prahl-Andersen B, Valk J, Kostense PJ, Tuinzing DB.
Computed tomography in evaluation of early secondary bone grafting. Int J Oral Maxillofac Surg 1994; 23: 132-136. 18.
Reinert S, Konig S, Bremerich A, Eufinger H, Krimmel M. Stability of bone
grafting and placement of implants in the severely atrophic maxilla. Br J Oral Maxillofac Surg 2003; 41: 249-255. 19.
Maiorana C, Beretta M, Battista Grossi G, Santoro F, Scott Herford A, Nagursky
H, Cicciu M. Histomorphometric evaluation of anorganic bovine bone coverage to reduce autogenous grafts resorption: preliminary results. Open Dent J 2011; 5: 71-78.
20. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Maiorana C, Beretta M, Salina S, Santoro F. Reduction of autogenous bone graft
resorption by means of bio-oss coverage: a prospective study. Int J Periodontics Restorative Dent 2005; 25: 19-25. 21.
Collins M, James DR, Mars M. Alveolar bone grafting: a review of 115 patients.
Eur J Orthod 1998; 20: 115-120. 22.
Tomford WW. Bone allografts: past, present and future. Cell Tissue Bank 2000;
1: 105-109. 23.
Sehn FP, Dias RR, de Santana Santos T, Silva ER, Salata LA, Chaushu G, Xavier
SP. Fresh-frozen allografts combined with bovine bone mineral enhance bone formation in sinus augmentation. J Biomater Appl 2015; 29: 1003-1013. 24.
Xavier SP, Dias RR, Sehn FP, Kahn A, Chaushu L, Chaushu G. Maxillary sinus
grafting with autograft vs. fresh frozen allograft: a split-mouth histomorphometric study. Clin Oral Implants Res 2015; 26: 1080-1085. 25.
Dias RR, Sehn FP, de Santana Santos T, Silva ER, Chaushu G, Xavier SP.
Corticocancellous fresh-frozen allograft bone blocks for augmenting atrophied posterior mandibles in humans. Clin Oral Implants Res 2014. 26.
Nissan J, Marilena V, Gross O, Mardinger O, Chaushu G. Histomorphometric
analysis following augmentation of the anterior atrophic maxilla with cancellous bone block allograft. Int J Oral Maxillofac Implants 2012; 27: 84-89. 27.
Nissan J, Marilena V, Gross O, Mardinger O, Chaushu G. Histomorphometric
analysis following augmentation of the posterior mandible using cancellous bone-block allograft. J Biomed Mater Res A 2011; 97: 509-513. 28.
Joyce MJ. American association of tissue banks: a historical reflection upon
entering the 21st century. Cell Tissue Bank 2000; 1: 5-8.
29. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Costain DJ, Crawford RW. Fresh-frozen vs. irradiated allograft bone in
orthopaedic reconstructive surgery. Injury 2009; 40: 1260-1264. 30.
Simonds RJ, Holmberg SD, Hurwitz RL, Coleman TR, Bottenfield S, Conley LJ,
Kohlenberg SH, Castro KG, Dahan BA, Schable CA, et al. Transmission of human immunodeficiency virus type 1 from a seronegative organ and tissue donor. N Engl J Med 1992; 326: 726-732. 31.
Nissan J, Ghelfan O, Mardinger O, Calderon S, Chaushu G. Efficacy of cancellous
block allograft augmentation prior to implant placement in the posterior atrophic mandible. Clin Implant Dent Relat Res 2011; 13: 279-285. 32.
Gorla LF, Spin Neto R, Boos FB, Pereira R dos S, Garcia-Junior IR, Hochuli-
Vieira E. Use of autogenous bone and beta-tricalciu phospate in maxillary sinus lifting: a prospective, randomized, volumetric computed tomography study. Int J Oral Maxillofac Implants 2015; 44: 1486-91. 33.
Mazzocco F, Lops D, Gobbato L, Lolato A, Romeo E, del Fabbro M. Three-
dimensional volume change of grafted bone in the maxillary sinus. Int J Oral Maxillofac Implants 2014; 29: 178-184. 34.
Spin-Neto R, Marcantonio E Jr, Gotfredesen E, Wensel A. Exploring CBCT-
based DICOM files. A systematic review on the properties of images used to evaluate maxillofacial bone grafts. J Digit Imaging 2011; 24: 959-66. 34.
Giannoudis PV, Dinopoulos H, Tsiridis E. Bone substitutes: an update. Injury
2005; 36 Suppl 3: S20-27. 35.
Stevenson S. Biology of bone grafts. Orthop Clin North Am 1999; 30: 543-552.
36.
Marx RE. Bone and bone graft healing. Oral Maxillofac Surg Clin North Am
2007; 19: 455-466, v.
37. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Simion M, Fontana F, Rasperini G, Maiorana C. Vertical ridge augmentation by
expanded-polytetrafluoroethylene membrane and a combination of intraoral autogenous bone graft and deproteinized anorganic bovine bone (Bio Oss). Clin Oral Implants Res 2007; 18: 620-629. 38.
Simion M, Dahlin C, Rocchietta I, Stavropoulos A, Sanchez R, Karring T. Vertical
ridge augmentation with guided bone regeneration in association with dental implants: an experimental study in dogs. Clin Oral Implants Res 2007; 18: 86-94. 39.
Bahat O, Fontanessi RV. Efficacy of implant placement after bone grafting for
three-dimensional reconstruction of the posterior jaw. Int J Periodontics Restorative Dent 2001; 21: 220-231. 40.
Nissan J, Mardinger O, Calderon S, Romanos GE, Chaushu G. Cancellous bone
block allografts for the augmentation of the anterior atrophic maxilla. Clin Implant Dent Relat Res 2011; 13: 104-111. 41.
Viscioni A, Franco M, Rigo L, Guidi R, Spinelli G, Carinci F. Retrospective study
of standard-diameter implants inserted into allografts. J Oral Maxillofac Surg 2009; 67: 387-393. 42.
Smolka W, Eggensperger N, Carollo V, Ozdoba C, Iizuka T. Changes in the
volume and density of calvarial split bone grafts after alveolar ridge augmentation. Clin Oral Implants Res 2006; 17: 149-155. 43.
Johansson B, Grepe A, Wannfors K, Hirsch JM. A clinical study of changes in the
volume of bone grafts in the atrophic maxilla. Dentomaxillofac Radiol 2001; 30: 157161. 44.
Ozaki W, Buchman SR. Volume maintenance of onlay bone grafts in the
craniofacial skeleton: micro-architecture versus embryologic origin. Plast Reconstr Surg 1998; 102: 291-299.
45. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Sbordone C, Toti P, Guidetti F, Califano L, Bufo P, Sbordone L. Volume changes
of autogenous bone after sinus lifting and grafting procedures: a 6-year computerized tomographic follow-up. J Craniomaxillofac Surg 2013; 41: 235-241. 46.
Spin-Neto R, Landazuri Del Barrio RA, Pereira LA, Marcantonio RA,
Marcantonio E, Marcantonio E, Jr. Clinical similarities and histological diversity comparing fresh frozen onlay bone blocks allografts and autografts in human maxillary reconstruction. Clin Implant Dent Relat Res 2013; 15: 490-497.
FIGURES LEGENDS Figure 1. Clinical intra-oral view of the atrophied posterior mandible alveolar ridge (A), A full thickness flap was performed for gaining acess to the surgical site (B) Recipient bone bed showing the perforations for improving graft vascularization (C), Final aspect of the block after shaping and fixation. (D), Bovine bone mineral granules (BBM) was used for covering the block (E), A resorbable collagenous membrane was positioned over the graft before wound closure (F). Table 1. Data expressed as mean ± standard deviation. Figure 2. Mimics output showing the methodology used for volumetric measurements of the grafts. Figure3. Boxplot of the vertical bone gain. T1: immediately after bone grafting; T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, ANOVA, H = 42.905, df = 2, p < 0.05).
Figure 4. Boxplot of horizontal bone gain. T1: immediately after bone grafting; T2: six 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, ANOVA, H = 68.843, df = 2, p < 0.05). Figure 5. Boxplot of the volumetric bone gain. T1: immediately after bone grafting; T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. * (eg, ANOVA, H = 66.139, df = 2, p < 0.05). Figure 6. Boxplot of the volumetric bone resorption. T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, Mann Whitney Test, U = 712.500, p < 0.05). Figure 7. Microtomography views and three dimensional reconstruction of a bone sample at six months postoperatively. Newly formed bone (blue arrows) and remaining grafted bone (yellow arrows). Figure 8. Histological findings (hematoxilin and eosin). Newly formed vital bone (blue arrows) in close contact to the remaining grafted bone yellow arrows) surrounded by connective tissue containing vessels (black arrows). Magnification, 10 x.
Figure 1A
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Figure 1B
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Figure 1C
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Figure 1D
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Figure 1E
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Figure 1F
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Figure 2
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Figure 3
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Figure 4
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Figure 5
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Figure 6
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Figure 7
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Figure 8
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Table
Click here to download Table Table 1.docx
Table 1. Clinical results Patients
Gender
Age
No.
Male Female
Years
Bone Blocks Molar
Pre-
Implants Molar
molar 20
5
15
51.8±7.51
32
18
Pre-
Torque
Survival Rate
Follow up
(N)
Block Implant
Months
molar 32
18
46±4.89 100%
96%
31.75±6.99
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aaid-joi-D-16-00095R1
Full Title:
Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible Augmentation
Short Title:
Stability of Fresh Frozen Bone Blocks in Mandible
Article Type:
Clinical Research
Keywords:
Fresh frozen bone allograft, atrophic mandible, histological analysis, tomographic analysis, dental implants.
Corresponding Author:
Erick Silva, PhD student School of Dentistry of Ribeirão Preto, University of São Paulo Ribeirão Preto, São Paulo BRAZIL
Corresponding Author Secondary Information: Corresponding Author's Institution:
School of Dentistry of Ribeirão Preto, University of São Paulo
Corresponding Author's Secondary Institution: First Author:
Erick Silva, PhD student
First Author Secondary Information: Order of Authors:
Erick Silva, PhD student Emanuela Prado Ferraz, PhD student Evandro Carneiro Martins Neto, PhD student Liat Chaushu, Resident Gavriel Chaushu, Associate Professor Samuel Porfirio Xavier, Associate Professor
Order of Authors Secondary Information: Abstract:
The aim of this prospective controlled study present study is to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using FFB. Twenty consecutive patients presenting for reconstruction of posterior mandibular alveolar bone ridge width ≤ 6.0 mm and/or height≤ 6.0 who met all inclusion and exlusion criteria were included. FFB blocks were used. The main outcome variable investigated was bone volume dynamics. Vertical, horizontal and three-dimensional bone gain data was measured from computerized tomography scans. The main predictor variable was time evaluated at three points: immediately after surgery (T1), at implant placement (T2) and 01 year after functional loading (T3). Secondary outcome parameters evaluated were implant survival, histological findings and microtomographic morphometry. Twenty-eight hemi-mandibles, 50 FFB bone blocks, 15 females and 5 male patients (mean age - 51.8 years). Block and implants survival rate were respectively 100% and 96% after 31.75 months of follow up. Vertical and horizontal bone gain at T2 was 5.15 and 6.42 mm respectively. Volumetric resorption was 31% at T2, followed by an additional 10% reduction at T3. Histological evaluation showed newly formed vital bone in intimate contact to the remaining FFB. Microtomography revealed 31.8% newly formed bone, 14.5% remaining grafted bone and 53.7% connective tissue and bone marrow. Thus, FFB blocks may lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implant-supported rehabilitation with high success rates.
Response to Reviewers:
Dear Mr. Jim Rutkowski, DMD, PhD Editor-in-Chief
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Journal of Oral Implantology We appreciate the reviewer’s comments (reviewer #2). All suggestions were well received by the authors. We also agree that the article will become more atractive and beneficial to JOI readers with the corrections. The modifications were highlighted in text. Please find bellow the suggested corrections: 1)Line 8. FFB. Please explain acronym. ANSWER: acronym was explained in the second line of the abstract (Page 1, line). 2)Abstract: bacterial or viral transmission of fresh frozen bone have to be discussed. ANSWER: We included a paragraph for bacterial/virus transmission discussion (Page 1, lines 1-3). Material and Methods: 3)explain the use of Mimics software. How the measurements were made? Who made the measurements? When Mimics software is used the measurements are operator dependent. ANSWER: In the section “Tomography”, we performed a fully detailed description of how all the measurements were made (see Page 6, lines 11-23). Four references were cited for better understanding of the methodology and also for complementary information. 4)was a CT scan performed preoperatively? ANSWER: Yes, a CT scan was performed preoperatively only for surgical planning. This CT scan was not used for measurements. We included a sentence to explain the finality of this scan (Page 6, lines 4-7). 5)Which is the origin of the fresh frozen bone? A tissue bank? ANSWER: Yes, all the bone blocks were obtained from a musculoskeletal tissue bank called UNIOSS (Marília, Brazil). This missing information was included in the text in the section “Study Design” (see Page 4, lines 21 and 22). 6)Description of surgery? FFB blocks fixation? Flap management? ANSWER: The description of surgical procedure was included in the section “Study Design” (see Page 5-6, lines 23-19). 7)Line 22. 8%+40%+44%=92% ???????? ANSWER: Sorry. Data was mistyped. The correct is as follows: “Eight percent of the grafts were used to gain height, 48% were used to gain width, and 44% to gain both height and width.” (see Page 8, lines 5-6). 8)Dental implants factory and characteristics? ANSWER: Please see Page 5, lines 16 and 17. This article is based on a clinical case series in order to evaluate grafting technique and its volumetric behaviour. We have previously published histological and clinical results in Clin Oral Implant Research - 2015 (Dias et al.). We believe that all the requests were fulfilled. Kind Regards, Erick Ricardo Silva, DDS, OMFS, MsC, PhD Student Department of Oral and Maxillofacial Surgery and Periodontology School of Dentistry of Ribeirão Preto – USP E-mail: [email protected]
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Article File
Volumetric Stability of Fresh Frozen Bone Blocks in Atrophic Posterior Mandible 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Augmentation Volumetric Stability of Fresh Frozen Bone Blocks in Mandible
Erick Ricardo Silva, DDS* Emanuela Prado Ferraz, DDS, MSc* Evandro Carneiro Martins Neto, DDS, PhD* Gavriel Chaushu, DMD, MSc** Liat Chaushu, DMD, MSc† Samuel Porfírio Xavier, DDS, PhD‡
* PhD student, Department of Oral and Maxillofacial Surgery and Periodontology, The School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. ** Associate Professor, Department of Oral and Maxillofacial Surgery, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Israel. †
Resident, Department of Periodontology, The Maurice and Gabriela Goldschleger
School of Dental Medicine, Tel Aviv University, Israel. ‡
Assistant Professor, Department of Oral and Maxillofacial Surgery and Periodontology,
The School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. Corresponding author:
Erick Ricardo Silva 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
PhD student, Department of Oral and Maxillofacial Surgery and Periodontology, Ribeirão Preto Dental School, University of São Paulo, Brazil. Tel: +55 16 3315 4053 e-mail: [email protected]
CONFLICT OF INTEREST Conflict of Interest and Source of Funding Statement: The authors declare that they have no conflict of interest related to this study.
ACKNOWLEDGEMENTS The authors would like to thank Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) for financial support. Sebastião Carlos Bianco and Adriana Luisa Gonçalves Almeida are acknowledged for technical assistance.
ABSTRACT Fresh frozen bone allografts (FFB) has become an alternative for bone augmentation in the last decades, especially because the absence of recent reports of disease transmission or immunologic reactions when it is used. The aim of this prospective controlled study present study is to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using. Twenty consecutive patients
presenting for reconstruction of posterior mandibular alveolar bone ridge width ≤ 6.0 mm 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
and/or height≤ 6.0 who met all inclusion and exlusion criteria were included. FFB blocks were used. The main outcome variable investigated was bone volume dynamics. Vertical, horizontal and three-dimensional bone gain data was measured from computerized tomography scans. The main predictor variable was time evaluated at three points: immediately after surgery (T1), at implant placement (T2) and 01 year after functional loading (T3). Secondary outcome parameters evaluated were implant survival, histological findings and microtomographic morphometry. Twenty-eight hemimandibles, 50 FFB bone blocks, 15 females and 5 male patients (mean age - 51.8 years). Block and implants survival rate were respectively 100% and 96% after 31.75 months of follow up. Vertical and horizontal bone gain at T2 was 5.15 and 6.42 mm respectively. Volumetric resorption was 31% at T2, followed by an additional 10% reduction at T3. Histological evaluation showed newly formed vital bone in intimate contact to the remaining FFB. Microtomography revealed 31.8% newly formed bone, 14.5% remaining grafted bone and 53.7% connective tissue and bone marrow. Thus, FFB blocks may lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implant-supported rehabilitation with high success rates. KEY WORDS: fresh frozen bone allograft, atrophic mandible, histological analysis, tomographic analysis, dental implants.
INTRODUCTION
The increasing predictability of modern dental implants has created an opportunity 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
for their installation in compromised sites.1 However, the presence of an adequate bone volume is necessary to allow correct implant positioning and provide long-term stable biomechanical results.2, 3 Therefore, implants should be placed in accordance both to prosthetic planning and bone availability.4, 5 Several surgical procedures for bone augmentation are currently being used. Autogenous bone graft, harvested from either intra6 or extraoral7 donor sites, is considered the gold standard8, 9 due its osteoconductive, osteoinductive and osteogenic properties.10 However, the use of autogenous bone might result in donor site morbidity as postsurgical pain, paresthesia and increased operative time and costs.11-16 Furthermore, graft resorption rates of up to 30% have been reported at the first year.17, 18 However, it has been suggested that the addition of bone bovine mineral to the graft surface reduces resorption.19, 20 In the past few years, fresh frozen bone allograft (FFB) has become an interesting alternative to overcome the disadvantages of autogenous bone.21, 22 The use of FFB has been widely reported for a variety of clinical situations as sinus augmentation23, 24 and onlay graft.25-27 The development of strict guidelines of tissue harvesting, processing, storing and record-keeping, considerably decreased the risk of primary infection and antigenicity.28-30 Nevertheless, only a few studies assessed the use of FFB in the posterior mandible.25, 27, 31 The purpose of the present study was to evaluate volumetric changes of newly created bone following reconstruction of the atrophic posterior mandible using FFB. The null hypothesis was that newly created bone will undergo dimensional changes time. The specific aims of the study are to measure: 1. linear (width and height) and 2.
Three-dimensional bone changes at three time points: immediately after bone grafting 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
(T1), six months postoperatively at implant placement (T2) and 1 year after functional loading (T3). Clinical results were assessed at T2 and T3, microtomographic and histological findings at T2. MATERIALS AND METHODS Study design Prospective controlled study. This study protocol was approved by the Ethical Committee for Human Studies (Committee CAAE: 01473512.4.0000.5419) School of Dentistry of Ribeirão Preto, University of São Paulo, Brazil. Twenty consecutive patients with posterior mandibular residual alveolar bone ridge width ≤ 6.0 mm and/or height≤ 6.0 were included in this study. Inclusion criteria were age ≥ 18 years old, good general and mental health, nonsmoking, good oral health and dental conditions with no active periodontal disease or occlusal problems. Exclusion criteria were compromised oral and/or general health (ASA III and IV patients), pregnancy, smoking, acute or chronic alcohol abuse, radiotherapy, and use of bisphosphonates. All surgeries were performed by the same experienced surgeon, according to the technique described by Dias et al. 201425. Patients were instructed to maintain strict oral hygiene in the two week that preceded both grafting and implant placement surgical procedures. Prophylactic amoxicilin (1g) was prescribed in all cases. For the grafting surgery, corticocancellous bone blocks from a musculoskeletal tissue bank (UNIOSS, Marilia, Brazil) were obtained from distal femoral epiphysis with approximate dimensions of 20 x 10 x 6 mm. Under local anestesia (2% mepivacaine with 1:100.000 epinephrine), a full thickness flap was performed for gaining acess to the alveolar ridge bone defect. In order to improve vascular graft nutrition, the native bed bone was
perforated on its cortical buccal aspect. FFB bone blocks were sculped and shaped 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
tridimensionally according to the bone defect using diamond burs and a micro saw. After passive adaptation of the shaped block over the alveolar defect, it was fixed in the proper position with 1.5 x 10 mm titanium screws (Synthes, Oberdorf, Switzerland). All blocks were perforated on the cortical aspect. The cortical sharp edges of the graft were removed with the same diamond burs and BBM 0.25-1.0 mm granules (Bio-Oss, Geistlich Pharma, Basel, Switzerland) were used to cover the block and proximal areas. The surgical site was completely covered with a resorbable collagenous membrane (Bio-Gide, Geistlich Pharma, Basel, Switzerland) before wound closuring (see Figure 1, A – F). Tension-free closure and passive sutures were achieved through internal periosteal release of the buccal flap and partial detachment of mylohyod muscle. The grafts healing time was 6 months. None of the patients were allowed to used any kind of prosthetic device during this period. At six months after grafting, a single biopsy was collected from each patient for histological analysis from the middle of the graft. In the same surgical procedure, conventional cone morse implants were installed (TitamaxCM Cortical, Neodent, Curitiba, Brazil). Six months after implant installation, the patients were rehabilitated prosthetically with cemented implanted-supported single tooth restorations and followed for 1 year after functional loading
Tomography 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Cone beam computerized tomography (CBCT) scans were taken immediately after the grafting surgery (T1), six months postoperatively at implant placement (T2) and 1 year after functional loading (T3). A CBCT scan was also performed before grafting procedure for surgical planning purpose, such as to investigate bone atrophy and inferior alveolar bundle position. This CBCT was not used for linear and volumetric measurements. The CBCT model iCat Classic (Imaging Science International, Hatfield, EUA) with exposure factors of 120 kV and 36.12 mAs with 0.25 mm reconstruction interval and slice thickness was used. The DICOM files were processed by Mimics version 8.13 (Materialise, Leuven, Belgium) to asses linear and volumetric changes at the different times of the study (see Figure 2). For linear measurements, fixation screws heads were used as reference points. The values found between the crest of residual alveolar rigde and the superior and lateral border of the the graft were used for evaluation of height and thickness, respectively. To determine the volume of the grafts, the area of the graft in all of the CT slices was measured. All measurements were performed on sagittal slices (cross-sections). The contour of the graft was manually traced on each CT slice. The contrast/exposure of the images was adjusted for better assessment of the delineation of structures. The graft area was calculated automatically with Mimics software. The graft volume was also automatically calculated, corresponding to the sum of all sagittal areas slices. This methodology has been widely used and this measurement protocol has become the most acceptable for bone graft evaluation32-34. An expertise technician performed both linear and volumetric measurements.
MicroCT
Bone biopsies were taken during implant surgery. Samples were passively 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
removed from the trephines and kept in 10% buffered formalin at pH 7.4 for 48 h and transferred to a solution of 70% ethanol for 72 hours. Micro-CT analysis was performed using the SkyScan 1172 system (Bruker-SkyScan, Kontich, Belgium). Morphometric analysis was used to quantify the percentage of the histological elements. Histology After micro-CT analyses, samples were submitted to histological assessment using hematoxilin and eosin (H&E) staining, according to Xavier et al. 201524. Histological evaluation aims to assess the presence/absence of newly formed vital bone, remaining grafted bone and connective tissue in the specimens. Statistical Analysis For statistical analyses, first a Shapiro-Wilk normality test showed a non-normal distribution of the data, which were expressed as mean ± standard deviation (SD). Statistical significance was determined by one way analysis of variance and the MannWhitney U test. The Tukey multiple comparison posttest was also used to isolate the group per groups that differed from the others. Both graft and implant survival were estimated using Kaplan-Meirer survival curves. The SigmaPlot version 11 software (Systat Software, Witzenhausen, Germany) was used for all analyses. A value of p < 0.05 was considered statistically significant. RESULTS Clinical Outcomes Table 1 summarizes the demographic data. A total of 20 patients (15 females and 5 males) with a mean age of 51.8 ± 7.5 years (ranging from 37 to 64) were included in
the study. Twenty eight hemi-mandibles were reconstructed with 50 FFB bone blocks. 32 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
blocks were used for molar region and 18 were used for pre-molar region. Eight percent of the grafts were used to gain height, 48% were used to gain width, and 44% to gain both height and width. All surgeries were well tolerated by the patients. No bone block was lost. Small expositions of the graft were observed between 15 and 45 postoperative days in 6 patients, and all of them were treated with 2% Chlorhexidine gel until spontaneous closure occurred within 10 days. Tomography Vertical bone gain at T1 was 5.15 ± 1.04 mm decreasing (24%) to 3.91 ± 0.94 mm at T2 = and additional 25% to 2.92 ± 0.71 mm at T3 (see Figure 3). Horizontal bone gain was 6.42 ± 1.20 mm at T1, decreasing (28%) to 4.64 ± 1.32 mm at T2 and additional 13% to 4.02 ± 0.71 mm at T3 (see Figure 4). Bone gain in horizontal dimension showed a tendency to exceed bone gain in vertical dimension over the entire evaluation period, although it was not statistically different (eg, ANOVA, p > 0.05). Volumetric bone gain was: T1 = 1176.62 ± 358.08 mm³; T2 = 785.78 ± 201.16 mm³ and T3 = 689.72 ± 187.45 mm³ (see Figure 5). Thus, general volumetric bone resorption of 31 ± 15% at T2, followed by an additional 10 ± 14% reduction was noted at T3 (see Figure 6). Six months after the grafting procedures (T2), 50 implants were installed with a torque of insertion of 46 ± 4.9 N/cm. Implant length ranged from 9.0 mm to 11.0 mm. Implant diameter was similar (3.75 mm). The implant survival rate was 96% after 31.8 ± 7 (ranging from 20 to 42) months of follow up. Two implants failed at second stage surgery. The clinical view of the bone around the implants was healthy and the reason for failure was probably lack of osseointegration.
MicroCT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Micro-CT images showed an intimate contact between newly formed bone and remaining grafted bone in all samples, resembling the histological findings (see Figure 7). Micro-CT morphometric analysis revealed newly formed bone = 31.8 ± 0.5%; remaining grafted bone = 14.5 ± 0.2%; connective tissue and bone marrow = 53.7 ± 0.5%. Histology The histological analysis revealed newly formed vital bone, remaining grafted bone and connective tissue in all specimens. Empty osteocyte lacunae were used for identification of the remaining grafted bone. Newly formed vital bone with viable osteocyte was found in intimate contact with remaining grafted bone. Osteoblasts were seen at the margins of the calcified regions. Blood vessels within the connective tissue were also found. No evidence of acute or chronic inflammation infiltrate was observed (see Figure 8).
DISCUSSION This study was designed to evaluate the dimensional changes of new gained bone following augmentation of atrophic posterior mandibles with corticocancellous FFB blocks. The grafting procedures enabled the adequate reconstruction of alveolar ridges for further implant placement. A similar grafting technique has been previously reported by Nissan et al.31 However, in the present study cortico-cancellous FFB blocks were used instead of cancellous freeze-dried bone allograft (FDBA) blocks. Corticocancellous bone blocks present a thin external cortical layer allowing easier locking of fixations screws and numerous internal cancellous sites for increasing graft perfusion.34-36 Furthermore,
FFB blocks were covered with BBM and a collagenous membrane once to assist in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
volumetric maintenance of the new gained bone.20, 25,37,38 It has been suggested that mandibular grafting is less predictable than grafting in the maxila.39 In this study, there were no complications related to the graft incorporation process, as graft block detachment of the recipient bone bed. All of the blocks were fully attached to the recipient sites during the entire time points (survival rate = 100%). This is compatible compared to previous reports.32, 40 In the present study, bone gain in vertical dimension and horizontal dimension resembled values reported by Nissan and colleagues.32 The new gained bone allowed adequate implant placement. All the implants showed proper primary stability (insertion torque = 46 ± 5N/cm). Only two out of fifty implants failed and had to be replaced (implant survival rate = 96%). These results of the present study are consistent with previously published data.25, 27, 31, 41 For any kind of graft, a major drawback is the volume reduction that occur with the time1. Most of the available studies evaluating the dimensional changes of the grafts have drawbacks.42-44 One of the limitations is the performance of the linear measurements. Linear measurement techniques depend on a reference point and they can easily under-or overestimate the results. Bone dynamics occurs in a non-uniform volumetric pattern.1 For this reason, three dimensional measurements are more accurate. It can be speculated that implant placement at T2 contributed to the decrease in the resorption rate of the new gained bone between T2 and T3.45 The microtomographic and histological analysis of the grafts after a follow up period of 6 months showed newly formed vital bone in contact to the remaining bone grafted. In this study, the morphometric findings were similar to those reported by Nissan
et al.27, Dias et al.25 and Spin-Neto and colleagues.46 The residual grafted bone did not 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
influence the implant osseointegration outcome, as demonstrated by the results. CONCLUSION Within the limits of the present study, FFB blocks lead to new bone formation and consolidation, with satisfactory volumetric bone maintenance, allowing implantsupported rehabilitation with high success rates.
REFERENCES 1.
Deluiz D, Oliveira LS, Pires FR, Tinoco EM. Time-dependent changes in fresh-
frozen bone block grafts: tomographic, histologic, and histomorphometric findings. Clin Implant Dent Relat Res 2015; 17: 296-306.
2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Ishikawa T, Salama M, Funato A, Kitajima H, Moroi H, Salama H, Garber D.
Three-dimensional bone and soft tissue requirements for optimizing esthetic results in compromised cases with multiple implants. Int J Periodontics Restorative Dent 2010; 30: 503-511. 3.
Bidra AS, Chapokas AR. Treatment planning challenges in the maxillary anterior
region consequent to severe loss of buccal bone. J Esthet Restor Dent 2011; 23: 354-360. 4.
Bidra AS. Surgical and prosthodontic consequences of inadequate treatment
planning for fixed implant-supported prosthesis in the edentulous mandible. J Oral Maxillofac Surg 2010; 68: 2528-2536. 5.
McAllister BS, Haghighat K. Bone augmentation techniques. J Periodontol 2007;
78: 377-396. 6.
Nowzari H, Aalam AA. Mandibular cortical bone graft part 2: surgical technique,
applications, and morbidity. Compend Contin Educ Dent 2007; 28: 274-280; quiz 281272. 7.
Donovan MG, Dickerson NC, Hanson LJ, Gustafson RB. Maxillary and
mandibular reconstruction using calvarial bone grafts and Branemark implants: a preliminary report. J Oral Maxillofac Surg 1994; 52: 588-594. 8.
Khan SN, Cammisa FP, Jr., Sandhu HS, Diwan AD, Girardi FP, Lane JM. The
biology of bone grafting. J Am Acad Orthop Surg 2005; 13: 77-86. 9.
Sajid MA, Warraich RA, Abid H, Ehsan-ul-Haq M, Shah KL, Khan Z.
Reconstruction of mandibular defects with autogenous bone grafts: a review of 30 cases. J Ayub Med Coll Abbottabad 2011; 23: 82-85. 10. 294.
Hoexter DL. Bone regeneration graft materials. J Oral Implantol 2002; 28: 290-
11. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Nkenke E, Radespiel-Troger M, Wiltfang J, Schultze-Mosgau S, Winkler G,
Neukam FW. Morbidity of harvesting of retromolar bone grafts: a prospective study. Clin Oral Implants Res 2002; 13: 514-521. 12.
Clavero J, Lundgren S. Ramus or chin grafts for maxillary sinus inlay and local
onlay augmentation: comparison of donor site morbidity and complications. Clin Implant Dent Relat Res 2003; 5: 154-160. 13.
Joshi A. An investigation of post-operative morbidity following chin graft
surgery. Br Dent J 2004; 196: 215-218; discussion 211. 14.
Joshi A, Kostakis GC. An investigation of post-operative morbidity following
iliac crest graft harvesting. Br Dent J 2004; 196: 167-171; discussion 155. 15.
von Arx T, Hafliger J, Chappuis V. Neurosensory disturbances following bone
harvesting in the symphysis: a prospective clinical study. Clin Oral Implants Res 2005; 16: 432-439. 16.
Silva FM, Cortez AL, Moreira RW, Mazzonetto R. Complications of intraoral
donor site for bone grafting prior to implant placement. Implant Dent 2006; 15: 420-426. 17.
van der Meij AJ, Baart JA, Prahl-Andersen B, Valk J, Kostense PJ, Tuinzing DB.
Computed tomography in evaluation of early secondary bone grafting. Int J Oral Maxillofac Surg 1994; 23: 132-136. 18.
Reinert S, Konig S, Bremerich A, Eufinger H, Krimmel M. Stability of bone
grafting and placement of implants in the severely atrophic maxilla. Br J Oral Maxillofac Surg 2003; 41: 249-255. 19.
Maiorana C, Beretta M, Battista Grossi G, Santoro F, Scott Herford A, Nagursky
H, Cicciu M. Histomorphometric evaluation of anorganic bovine bone coverage to reduce autogenous grafts resorption: preliminary results. Open Dent J 2011; 5: 71-78.
20. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Maiorana C, Beretta M, Salina S, Santoro F. Reduction of autogenous bone graft
resorption by means of bio-oss coverage: a prospective study. Int J Periodontics Restorative Dent 2005; 25: 19-25. 21.
Collins M, James DR, Mars M. Alveolar bone grafting: a review of 115 patients.
Eur J Orthod 1998; 20: 115-120. 22.
Tomford WW. Bone allografts: past, present and future. Cell Tissue Bank 2000;
1: 105-109. 23.
Sehn FP, Dias RR, de Santana Santos T, Silva ER, Salata LA, Chaushu G, Xavier
SP. Fresh-frozen allografts combined with bovine bone mineral enhance bone formation in sinus augmentation. J Biomater Appl 2015; 29: 1003-1013. 24.
Xavier SP, Dias RR, Sehn FP, Kahn A, Chaushu L, Chaushu G. Maxillary sinus
grafting with autograft vs. fresh frozen allograft: a split-mouth histomorphometric study. Clin Oral Implants Res 2015; 26: 1080-1085. 25.
Dias RR, Sehn FP, de Santana Santos T, Silva ER, Chaushu G, Xavier SP.
Corticocancellous fresh-frozen allograft bone blocks for augmenting atrophied posterior mandibles in humans. Clin Oral Implants Res 2014. 26.
Nissan J, Marilena V, Gross O, Mardinger O, Chaushu G. Histomorphometric
analysis following augmentation of the anterior atrophic maxilla with cancellous bone block allograft. Int J Oral Maxillofac Implants 2012; 27: 84-89. 27.
Nissan J, Marilena V, Gross O, Mardinger O, Chaushu G. Histomorphometric
analysis following augmentation of the posterior mandible using cancellous bone-block allograft. J Biomed Mater Res A 2011; 97: 509-513. 28.
Joyce MJ. American association of tissue banks: a historical reflection upon
entering the 21st century. Cell Tissue Bank 2000; 1: 5-8.
29. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Costain DJ, Crawford RW. Fresh-frozen vs. irradiated allograft bone in
orthopaedic reconstructive surgery. Injury 2009; 40: 1260-1264. 30.
Simonds RJ, Holmberg SD, Hurwitz RL, Coleman TR, Bottenfield S, Conley LJ,
Kohlenberg SH, Castro KG, Dahan BA, Schable CA, et al. Transmission of human immunodeficiency virus type 1 from a seronegative organ and tissue donor. N Engl J Med 1992; 326: 726-732. 31.
Nissan J, Ghelfan O, Mardinger O, Calderon S, Chaushu G. Efficacy of cancellous
block allograft augmentation prior to implant placement in the posterior atrophic mandible. Clin Implant Dent Relat Res 2011; 13: 279-285. 32.
Gorla LF, Spin Neto R, Boos FB, Pereira R dos S, Garcia-Junior IR, Hochuli-
Vieira E. Use of autogenous bone and beta-tricalciu phospate in maxillary sinus lifting: a prospective, randomized, volumetric computed tomography study. Int J Oral Maxillofac Implants 2015; 44: 1486-91. 33.
Mazzocco F, Lops D, Gobbato L, Lolato A, Romeo E, del Fabbro M. Three-
dimensional volume change of grafted bone in the maxillary sinus. Int J Oral Maxillofac Implants 2014; 29: 178-184. 34.
Spin-Neto R, Marcantonio E Jr, Gotfredesen E, Wensel A. Exploring CBCT-
based DICOM files. A systematic review on the properties of images used to evaluate maxillofacial bone grafts. J Digit Imaging 2011; 24: 959-66. 34.
Giannoudis PV, Dinopoulos H, Tsiridis E. Bone substitutes: an update. Injury
2005; 36 Suppl 3: S20-27. 35.
Stevenson S. Biology of bone grafts. Orthop Clin North Am 1999; 30: 543-552.
36.
Marx RE. Bone and bone graft healing. Oral Maxillofac Surg Clin North Am
2007; 19: 455-466, v.
37. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Simion M, Fontana F, Rasperini G, Maiorana C. Vertical ridge augmentation by
expanded-polytetrafluoroethylene membrane and a combination of intraoral autogenous bone graft and deproteinized anorganic bovine bone (Bio Oss). Clin Oral Implants Res 2007; 18: 620-629. 38.
Simion M, Dahlin C, Rocchietta I, Stavropoulos A, Sanchez R, Karring T. Vertical
ridge augmentation with guided bone regeneration in association with dental implants: an experimental study in dogs. Clin Oral Implants Res 2007; 18: 86-94. 39.
Bahat O, Fontanessi RV. Efficacy of implant placement after bone grafting for
three-dimensional reconstruction of the posterior jaw. Int J Periodontics Restorative Dent 2001; 21: 220-231. 40.
Nissan J, Mardinger O, Calderon S, Romanos GE, Chaushu G. Cancellous bone
block allografts for the augmentation of the anterior atrophic maxilla. Clin Implant Dent Relat Res 2011; 13: 104-111. 41.
Viscioni A, Franco M, Rigo L, Guidi R, Spinelli G, Carinci F. Retrospective study
of standard-diameter implants inserted into allografts. J Oral Maxillofac Surg 2009; 67: 387-393. 42.
Smolka W, Eggensperger N, Carollo V, Ozdoba C, Iizuka T. Changes in the
volume and density of calvarial split bone grafts after alveolar ridge augmentation. Clin Oral Implants Res 2006; 17: 149-155. 43.
Johansson B, Grepe A, Wannfors K, Hirsch JM. A clinical study of changes in the
volume of bone grafts in the atrophic maxilla. Dentomaxillofac Radiol 2001; 30: 157161. 44.
Ozaki W, Buchman SR. Volume maintenance of onlay bone grafts in the
craniofacial skeleton: micro-architecture versus embryologic origin. Plast Reconstr Surg 1998; 102: 291-299.
45. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Sbordone C, Toti P, Guidetti F, Califano L, Bufo P, Sbordone L. Volume changes
of autogenous bone after sinus lifting and grafting procedures: a 6-year computerized tomographic follow-up. J Craniomaxillofac Surg 2013; 41: 235-241. 46.
Spin-Neto R, Landazuri Del Barrio RA, Pereira LA, Marcantonio RA,
Marcantonio E, Marcantonio E, Jr. Clinical similarities and histological diversity comparing fresh frozen onlay bone blocks allografts and autografts in human maxillary reconstruction. Clin Implant Dent Relat Res 2013; 15: 490-497.
FIGURES LEGENDS Figure 1. Clinical intra-oral view of the atrophied posterior mandible alveolar ridge (A), A full thickness flap was performed for gaining acess to the surgical site (B) Recipient bone bed showing the perforations for improving graft vascularization (C), Final aspect of the block after shaping and fixation. (D), Bovine bone mineral granules (BBM) was used for covering the block (E), A resorbable collagenous membrane was positioned over the graft before wound closure (F). Table 1. Data expressed as mean ± standard deviation. Figure 2. Mimics output showing the methodology used for volumetric measurements of the grafts. Figure3. Boxplot of the vertical bone gain. T1: immediately after bone grafting; T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, ANOVA, H = 42.905, df = 2, p < 0.05).
Figure 4. Boxplot of horizontal bone gain. T1: immediately after bone grafting; T2: six 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, ANOVA, H = 68.843, df = 2, p < 0.05). Figure 5. Boxplot of the volumetric bone gain. T1: immediately after bone grafting; T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. * (eg, ANOVA, H = 66.139, df = 2, p < 0.05). Figure 6. Boxplot of the volumetric bone resorption. T2: six months postoperatively at implant placement; T3: 1 year after functional loading. Median, minimum, maximum, and standard deviation. *(eg, Mann Whitney Test, U = 712.500, p < 0.05). Figure 7. Microtomography views and three dimensional reconstruction of a bone sample at six months postoperatively. Newly formed bone (blue arrows) and remaining grafted bone (yellow arrows). Figure 8. Histological findings (hematoxilin and eosin). Newly formed vital bone (blue arrows) in close contact to the remaining grafted bone yellow arrows) surrounded by connective tissue containing vessels (black arrows). Magnification, 10 x.
Figure 1A
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Figure 1B
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Figure 1C
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Figure 1D
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Figure 1E
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Figure 1F
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Figure 2
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Figure 3
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Figure 4
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Figure 5
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Figure 6
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Figure 7
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Figure 8
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Table
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Table 1. Clinical results Patients
Gender
Age
No.
Male Female
Years
Bone Blocks Molar
Pre-
Implants Molar
molar 20
5
15
51.8±7.51
32
18
Pre-
Torque
Survival Rate
Follow up
(N)
Block Implant
Months
molar 32
18
46±4.89 100%
96%
31.75±6.99
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