Autogenous Bone Graft Group Research Articles

The effect of injectable platelet-rich fibrin in combination with autogenous bone grafts on bone healing in an ovariectomized osteoporotic rat model with critical-sized defects.

To assess the impact of autogenous graft materials, including autogenous bone graft (ABG) and injectable platelet-rich fibrin (I-PRF) clots, on bone defect regeneration in ovariectomized osteoporotic rats. Wistar rats (6-8 weeks old) were ovariectomized, and surgery began after 8 weeks. A 5-mm defect was created bilaterally in the parietal bones of 16 rats, which were divided into 4 groups. Group A (blank) had untreated defects; group B had defects filled with 0.1 ml of I-PRF, group C had defects filled with 0.1 ml of ABG, and group D had defects filled with a combination of 0.1 ml each of I-PRF and ABG. Four weeks post-surgery, the rats were euthanized. Bone regeneration was evaluated through histopathologic analysis and microcomputed tomography (micro-CT). In ovariectomized rats treated with ABG or I-PRF, bone regeneration was enhanced, with increased periosteal activity, osteoblast count, and new bone volume, as determined histologically. The ABG+I-PRF group had the highest periosteal vascularity, but the difference compared to the ABG group was not statistically significant (p>0.05). Osteoblast numbers were significantly higher in the ABG+I-PRF group than in the blank group (p<0.05). Micro-CT showed the highest mean new bone volume ratio in the ABG+I-PRF group, followed by the ABG group. The combined use of ABG and I-PRF enhances bone formation in osteoporotic rats following ovariectomy.

Clinical and radiographic evaluation of the use of PRF, CGF, and autogenous bone in the treatment of periodontal intrabony defects: Treatment of periodontal defect by using autologous products.

The purpose of this randomized clinical study was to clinically evaluate and compare the efficiencies of platelet-rich fibrin (PRF), concentrated growth factor (CGF) and autogenous bone graft (ABG) in the treatment of intrabony pockets and to assess the alveolar bone gain (AB gain) radiographically (panoramic and CBCT images). Eighty intrabony pockets were divided into four groups: ojnly open flap debridement (OFD), OFD+PRF, OFD+CGF and OFD+ABG; each group consisted of 20 defects. Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and tooth mobility (TM) by using Periotest M device were evaluated. Radiographic images were also taken to evaluate the AB gain. PRF was produced using a protocol of 2,700 RPM for 12 min and the relative centrifugal force (RCF) was evaluated. CGF was prepared as follows: 2min 2700rpm, 4min 2400rpm, 4min 2700rpm, 3min 3000rpm. The study results revealed a similar improvement in PI and GI values in all groups (p>0.05). There was a statistically significant decrease in PD and CAL in favor of ABG group at day 180 in comparison with other groups (p=0.001). There was also a statistically significant decrease in TM and alveolar bone height loss (ABHL), whereby the AB gain gradually increased among the groups with the best group being ABG, followed by CGF, PRF, and control groups, respectively (p=0.001). The study results support the treatment of periodontal intrabony pockets using OFD in combination with ABG, CGF, and PRF, as ABG showed the best results followed by CGF and PRF.

Vertical Ridge Augmentation Using Distraction Osteogenesis Versus Autogenous Bone Grafting: A Systematic Review and Meta-Analysis.

The aim of this systematic review was to systematically assess the papers comparing the surgical techniques of Alveolar Distraction Osteogenesis(ADO) and Autogenous Bone grafting (ABG) for Vertical Ridge Augmentation in terms of bone gain, bone resorption and incidences of complications. The review was registered on PROSPERO with the ID : CRD42021237671. A broad electronic survey was conducted in the PubMed, Scopus, Web of Science, Cochrane Library, and Virtual Health Library databases of all studies published till 08/03/2022. Four studies fulfilled the criteria to carry out a meta-analysis a in which a total of 58 patients underwent ADO and 43 patients for ABG. A total of 133 implants were placed in the ABG group and 124 in the ADO group. DerSimonian-Laird estimator of variance was used for Random effect meta-analysis. The estimates of an intervention were expressed as the odds ratio (OR) and standard mean difference (SMD) in millimeters. There was statistically significant difference in terms of bone height gain with SMD of - 0.78 (95% 0.04-1.55) in ABG. Bone resorption and complications were statistically insignificant with SMD of 0.52 (95% - 1.59 to 0.56) and OR 0.55 (95% 0.18-1.70), respectively.PROSPERO Registration ID: CRD42021237671.

Comparison of demineralized bone matrix with different cycling crushing times in posterolateral fusion model of athymic rats.

Decalcified bone matrix (DBM) is a widely used alternative material for bone transplantation. In the DBM production process, an effective particle size and the highest utilization rate of raw materials can be achieved only through multiple high-speed circulating comminution. The rat posterolateral lumbar fusion model (PLF) is the most mature small animal model for the initial evaluation of the efficacy of graft materials for bone regeneration and spinal fusion. To evaluate the differences in the in vivo osteogenic effects of DBM pulverization through 1, 5, 9, and 14 high-speed cycles, sixty athymic rats were divided into six groups: single cycling crushing (CC1), 5 cycles of crushing (CC5), 9 cycles of crushing (CC9), 13 cycles of crushing (CC13), autogenous bone graft (ABG) and negative control (NC). Posterolateral lumbar fusion was performed. Six weeks after surgery, the bilateral lumbar fusion of athymic rats was evaluated through manual palpation, X-ray, micro-CT and histological sections. Rank data were tested by the rank-sum test, and nonparametric data were tested by the Kruskal‒Wallis H test. The manual palpation and X-ray results showed that the fusion rate did not significantly differ between the CC1, CC5, CC9, CC13 and ABG groups. However, cavities appeared in CC9 and CC13 on the micro-CT image. The bone mass (BV/TV) of CC1, CC5, CC9 and CC13 was better than that of the ABG group, while almost no osteogenesis was observed in the NC group. Histologically, there was no obvious difference between the four groups except that the CC9 group and CC13 group had more fibrous tissues in the new bone. In conclusion, DMB with different cycling crushing times has no obvious difference in fusion rate of PLF, but it is slightly better than the ABG group.

Histopathological and radiographical evaluation of caprine demineralized bone matrix in a critical ulnar defect in a rabbit model

BackgroundCaprine species satisfy the conditions of an ideal donor animal when compared to bovine species that has been extensively studied and commercialized for bone xenograft. Histopathological and radiological evaluations of caprine demineralized bone matrix (CDBM) were therefore carried out for fracture healing properties for its possible use in bone grafting procedures.Materials and methodsTwenty-four rabbits were used for this study and were divided randomly into three groups of eight (n = 8) rabbits each. Critical bone defect was created on the ulnar diaphysis under xylazine-ketamine anaesthesia for autogenous bone graft (ABG) group, CDBM group and the last group was left unfilled as negative control (NC). Immediate post-grafting radiograph was taken and repeated on days 14, 28, 42 and 56 to monitor the evidence of radiographic healing. The animals were euthanized on day 56 and defect sites were harvested for histopathology.ResultsThere was a progressive evidence of radiographic healing and bone formation in all the groups with significance difference (P = 0.0064). When compared with ABG, NC differ significantly (P < 0.0001) whereas the CDBM did not differ significantly (P = 0.6765). The histopathology sections of ABG and CDBM showed normal bone tissue while the NC section was predominated by fibrous connective tissue. There was therefore an overall significant difference (P = 0.0001) in which CDBM did not differ from ABG (P = 0.2946) while NC did (P = 0.0005).ConclusionThe ABG and CDBM groups showed a similar healing effect in the critical bone defect. Therefore, CDBM could be used as an effective alternative to ABG in orthopaedics to circumvent the limitations and complications associated with it.Level of evidenceNot applicable.

Clinical outcomes of open-wedge corrective osteotomy using autogenous or allogenic bone grafts for malunited distal radius: A novel parameter for measuring the rate of bone union.

The aims of the study were (1) to compare outcomes in terms of malunited distal radius bone union in open-wedge corrective osteotomy using autogenous or allogenic bone and (2) to introduce a new parameter that quantifies the rate of the bone union. This retrospective study included 22 patients (14 males, 8 females) who underwent open-wedge corrective osteotomy with bone grafting for a malunited distal radius fracture between January 2006 and December 2018 were enrolled. The mean follow-up duration was 57.2 weeks (SD 46.1, range 12-206). All the patients were then divided into 1 of the 2 groups based on the graft material used: autog- enous bone graft group (n=10, 5 males and 5 females) and allogenic bone graft group (n=12, 9 males and 3 females). We introduced the "duration of union/correction gap ratio" to represent the healing potential of each graft materials. Radiologic parameters including initial correction gap, radial inclination, radial length, palmar tilt, and ulnar variance were also measured pre- and postoperatively. Functional outcomes were assessed by grip strength, range of motion, and the disability of the Arm, Shoulder, and Hand score. Of the 22 patients, 16 (72.7%) achieved complete union within 12 weeks, 3 (13.6%) in over 12 weeks, and the other 3 (13.6%) showed nonunion. Excluding the 3 nonunion cases, the mean union duration was 10.6 weeks, and the mean correction gap was 10 mm. The mean correction gap was wider in the autogenous bone graft group, and the mean union duration was longer in the allogenic bone graft group. Autogenous bone grafts had a significantly lower duration of bone union/correction gap ratio than allogenic bone grafts (0.76 vs. 1.61, P < 0.001). According to the correction method (simple open-wedge corrective osteotomy vs. open-wedge corrective oste- otomy OWCO), only duration of bone union/correction gap ratio reflected the actual difference between values. Despite autogenous bone graft donor site morbidities, in our study, autogenous bone showed better bone healing potential than allogenic bone. In terms of bone union, autogenous bone has the benefit of better union in larger gaps than allogenic bone. Surgeons can take advantage of the newly introduced "duration of bone union/correction gap ratio" to compare the bone healing potential by graft materials or surgical options. Level IV, Therapeutic Study.

Evaluation of Two Beta-Tricalcium Phosphates with Different Particle Dimensions in Human Maxillary Sinus Floor Elevation: A Prospective, Randomized Clinical Trial.

This study aimed to compare two beta-tricalcium phosphates with different particle sizes in human maxillary sinuses lifting. The immunolabeling of cells for RUNX2 and VEGF were performed to evaluate the osteoblast precursor cells and the vascular formation after 6 months of bone repair. Ten maxillary sinuses were grafted with autogenous bone graft (Group 1), 10 were grafted with ChronOs® (Group 2), and 10 were grafted with BETA-TCP® (Group 3). After 6 months of bone healing, biopsies were obtained to assess the new bone formed by histomorphometric and immunohistochemical evaluation for RUNX2 and VEGF. The mean bone formation for Group 1 was 51.4 ± 17.4%. Group 2 presented 45.5 ± 9.9%, and Group 3 conferred 35.4 ± 8.0% of new bone formation. The RUNX2 offered low for Groups 1 and 2 with high cellular activity for osteoblast in Group 3. The VEGF immunolabeling was moderate for Groups 1 and 2 and intense for Group 3. In conclusion, it was possible to show that the bone substitutes evaluated in the present study presented suitable outcomes for bone regeneration, being an alternative for the autogenous bone graft in maxillary sinus bone height reconstruction.

Immediate Implant Placement in Maxillary Esthetic Zone without Augmenting the Jumping Gap versus the Use of Autogenous Bone Particulates or Demineralized Bovine Bone Graft (Randomized Clinical Trial)

Aim: to assess Immediate Implant Placement in Maxillary Esthetic Zone without Augmenting the Jumping Gap versus the Use of Autogenous Bone Particulates or Demineralized Bovine Bone Graft. Material and Methods: This was a Randomized parallel controlled clinical trial conducted on 30 implant sites that indicated immediate implant placement in the maxillary esthetic zone divided into 3 groups equally: In group (A): immediate implants were inserted in the esthetic maxillary zone with no graft in the jumping gap. In group (B): immediate implants were inserted in the esthetic maxillary zone with demineralized bovine bone mineral (DBBM) in the jumping gap. In group (C): immediate implants were inserted in the esthetic maxillary zone with autogenous bone graft in the jumping gap. CBCT scans were performed immediately after the surgery and 6 months later for measuring horizontal bone changes at 3 levels (platform, mid implant, and apex level) of the labial plate of the bone and vertical bone changes labial and palatal plate of bone. Results: The mean horizontal bone loss at platform level was 1.57±0.283mm, 0.845±0.167 mm, and 1.226 mm at groups A (graft less group), B (xenograft group), and C (autogenous group) respectively. While at mean mid implant level was 1.155±0.3 mm,0.754±0.185 mm, and 0.829±0.31 mm at group A (graft less group), B (xenograft group) & C (autogenous group) respectively. Conclusion: the use of DBBM as a graft in the jumping gap showed the least bone dimensional changes compared to no graft and autogenous bone graft group in immediate implant placement.

Anterior Spinal Fusion Using Autologous Bone Grafting via the Lateral Approach with Posterior Short-Range Instrumentation for Lumbar Pyogenic Spondylitis with Vertebral Bone Destruction Enables Early Ambulation and Prevents Spinal Deformity.

Introduction Pyogenic spondylitis of the lumbar spine markedly decreases the ability to perform activities of daily living and causes severe low back pain. The challenge is to improve low back pain and activities of daily living performance earlier and prevent post-infection sequelae, and conservative treatment with antibiotics is the mainstay of treatment. Methods In the present study, patients who were unable to walk following lumbar pyogenic spondylitis even in the subacute phase after successful infection control, showing bone defects expanding from endplate to vertebral body in CT, were treated with posterior percutaneous short-range instrumentation and anterior autogenous bone grafting (group S, n = 10) or with conservative treatment alone (group C, n = 10). Acute cases of absolute surgical indication with paralytic symptoms and mild cases who could walk by antibiotics administration were excluded. The two groups were compared regarding the post-treatment change in C-reactive protein level, duration of bed rest, and post-infection local spinal deformities (local scoliosis angle in the coronal plane and local kyphosis angle in the sagittal plane). Results Compared with group C, group S took a significantly shorter time for the C-reactive protein level to return to normal and required a significantly shorter duration of bed rest. Furthermore, surgery prevented the formation of kyphosis and scoliosis, while group C developed local kyphosis. Conclusions The minimally invasive surgical method of posterior percutaneous short-range instrumentation and anterior autogenous bone grafting effectively enables early control of pain and maintenance of locomotive function and prevents spinal deformity in patients with lumbar pyogenic spondylitis in the subacute phase with advanced vertebral bone destruction.

Comparison of autogenous bone graft and tissue-engineered bone graft in alveolar cleft defects in canine animal models using digital radiography.

Autogenous bone graft is the gold standard for repair of bone defects. However, osteoprogenitor stem cells are suggested as an alternative treatment. Aims: To quantitatively compare bone formation in autogenous bone graft and tissue-engineered graft using digital radiography densitometry software in canine alveolar cleft model. This experimental study on animal models was conducted in Isfahan University of Medical Sciences. Mesenchymal stem cells (MSCs) were obtained from subcutaneous adipose tissue of 4 dogs. Undifferentiated cells were incubated with a hydroxyapatite/beta-tricalcium phosphate scaffold in an osteogenic medium for 21 days. A maxillary defect simulating human alveolar cleft was created from the alveolar crest to nasal floor with 15 mm width bilaterally. Two months later, the defect was filled with autogenous bone graft harvested from tibia on one side and tissue-engineered graft from MSCs on the other side. Digital radiography was performed on days 15, 30, 45, 60, 75, and 90 after grafting. Radiographic density was calculated by the mean numeric value of pixels of the desired area ranging from 0 (darkest) to 255 (lightest) by associated software. The data were analyzed by Statistical Package for the Social Sciences using descriptive statistics and two-way repeated-measure analysis of variance test (α = 0.05). Mean density measured for autogenous bone graft group was 110.72, 82.70, 75.76, 93.57, 100.22, and 100.32 in days 15, 30, 45, 60, 75, 90, respectively and 120.7, 87.62, 83.72, 92.02, 92.30, and 93.77 in stem cell group. Although the time lapse was a significant factor in two groups (P = 0.01), the results indicated that the difference between two groups was not statistically significant (P = 0.942). Tissue-engineering can be used as an alternative method in reconstruction of bony defects with predictable clinical outcomes.

Is It Necessary to Perform the Second Surgery Stage of Anterior Debridement in the Treatment of Spinal Tuberculosis?

In this retrospective comparative study, the efficacy and clinical outcomes of long posterior instrumentation, with or without laminectomy, were evaluated and the necessity of the second stage of anterior debridement in the treatment of spinal tuberculosis (TB) was discussed. This retrospective study included 41 patients who were diagnosed with spinal TB between January 2010 and June 2016. A total of 18 patients had received long posterior instrumentation, with or without laminectomy (group A), whereas the other 23 patients had posterior instrumentation plus anterior debridement and autogenous bone grafting (group B). The surgical information, clinical effectiveness, laboratory tests, and imaging results were compared between the 2 groups. One patient in group B died. Sinus drainage and incomplete bone fusion were discovered 1 year postoperatively. TB symptoms were significantly improved after surgery compared with those before surgery (P < 0.05), and there was no significant difference in the treatment efficacy between the 2 groups at the final follow-ups (P > 0.05). Compared with those of group B, the surgical time, bed-rest time, and hospitalization time of group A were all significantly shorter (P < 0.05), whereas the times before abscesses disappeared, bone graft fusion, and erythrocyte sedimentation rate returning to normal were all significantly longer (P < 0.05). Single-stage long posterior instrumentation, with or without laminectomy, is a safe, effective, and feasible method for the treatment of spinal TB. The second stage of anterior debridement surgery may not be necessary for every spinal TB treatment.

A Modified Weaver-Dunn Procedure with or without Chip Bone Graft for the Treatment of Acromioclavicular Joint Separation.

Background:In spite of frequent injuries to the acromioclavicular (AC) joint, there is no consensus regarding optimal technique to be used. This cohort study evaluated the clinical results of a modified Weaver-Dunn procedure with or without chip bone graft for the treatment of AC joint separation retrospectively.Materials and Methods:60 consecutive patients with AC joint separation, between the age of 19-76 years (mean age 43 years), were enrolled between January 2005 and September 2011. Forty patients (35 men, 5 women) were treated with a modified Weaver-Dunn procedure, and did not receive bone graft during the procedure (Group 1), whereas twenty patients (19 men, 1 woman) received autogenous chip bone graft (Group 2). Stability of the AC joint was evaluated clinically and radiographically, and the clinical results were assessed by the Imatani evaluation system.Results:The mean duration of followup was 2 years and 2 months. The results were excellent in all patients except one. At final followup, roentgenographic measurement revealed that the mean coracoclavicular interval was 8.2 mm on the affected side, and 8.9 mm on the unaffected side in Group 1, and 9.5 mm on the affected side and 10.1 mm on the unaffected side in Group 2. For Group 1, there were significant differences between augmentation of the grafted coracoacromial (CA) ligament antero-posteriorly and laterally (Option B) and repair of the torn AC ligament with augmentation of the grafted CA ligament antero-inferiorly (option A; P = 0.0351).Conclusions:The modified Weaver-Dunn procedure (Group 1 and 2) provides a stable and strong reconstruction for the treatment of AC joint separation. In addition, this modified Weaver-Dunn procedure with chip bone graft (Group 2) may lead to same or more secure healing of the grafted CA ligament-bone than the same procedure without chip bone graft (P = 0.9737).

Comparative study of volumetric changes and trabecular microarchitecture in human maxillary sinus bone augmentation with bioactive glass and autogenous bone graft: a prospective and randomized assessment

The aim of this study was to compare the volumetric changes and the new bone microarchitecture in human maxillary sinuses augmented with bioactive glass (Biogran) alone, bioactive glass combined with autogenous bone graft (1:1), or autogenous bone graft alone. Twelve maxillary sinuses were grafted with bioactive glass (group 1), nine with bioactive glass mixed with autogenous bone graft 1:1 (group 2), and 12 with autogenous bone graft (group 3). Patients underwent cone beam computed tomography 15days after the procedure to determine the initial volume of the graft (T1) and again 6 months later (T2). Biopsies were obtained at the time of dental implant placement and were subjected to micro-computed tomography. The volumetric change was 44.2% in group 1, 37.9% in group 2, and 45.7% in group 3 (P>0.05). The trabecular microarchitecture results showed that the materials used in groups 1 and 2 were good bone substitutes. However, the addition of 50% bioactive glass to autogenous bone graft improved the microarchitecture of the graft. Furthermore, the results for volumetric changes indicated that bioactive glass, its association with autogenous bone graft in a 1:1 ratio, and autogenous bone graft alone have similar resorption.

Healing mechanism and osteogenic capacity of bovine bone mineral—human amniotic mesenchymal stem cell and autogenous bone graft in critical size mandibular defect

Background: Maxillofacial bone engineering showed promising result; however, its healing mechanisms and effectiveness had not been fully understood. Objectives: The study compared the bone healing mechanism and osteogenic capacity between bovine bone mineral (BBM) scaffold loaded with human amniotic membrane stem cell (hAMSC) and autogenous bone graft (ABG) in the reconstruction of critical size mandibular defect. Methods: Critical size defects were made at mandible of 45 New Zealand White rabbits which were subsequently reconstructed with BBM-hAMSC, BBM alone, and ABG, respectively. At the end of first, second, and twelfth weeks, five rabbits from each group were sacrificed for histology and immunohistochemistry staining. Expressions of vascular endothelial growth factor (VEGF), bone morphogenetic protein-2 (BMP-2), Runt-related transcription factor 2 (Runx2) and angiogenesis were analysed in first and second week, while Runx2, osteocalcin, collagen-I fibres, trabecular area and bone incorporation were analysed in twelfth week. Findings: Expressions of VEGF, BMP-2, Runx2 and angiogenesis were higher in ABG compared with BBM-hAMSC group in the first and second week group. In twelfth week expressions of Runx2 and osteocalcin as well as thickness of collagen-I fibres were significantly higher in BBM-hAMSC compared to ABG group, while there was no statistically difference in trabecular area and bone incorporation between BBMhAMSC and ABG group. Conclusion: Early healing activities were higher in ABG than in BBM-hAMSC, while osteogenic activities in the late stage of healing were higher in BBM-hAMSC compared to ABG. In addition, the osteogenic capacity of BBM-hAMSC was comparable to ABG in the reconstruction of critical size defect in the mandible.

Use of autogenous bone and beta-tricalcium phosphate in maxillary sinus lifting: histomorphometric study and immunohistochemical assessment of RUNX2 and VEGF

The aim of this study was to compare the use of beta-tricalcium phosphate (β-TCP) (chronOS) with autogenous bone grafts alone in maxillary sinus elevation surgery. The test samples were β-TCP alone, β-TCP mixed with autogenous bone grafts (1:1), and autogenous bone grafts alone. Twelve maxillary sinuses were grafted with β-TCP (group 1), nine with β-TCP+autogenous bone graft (group 2), and 12 with autogenous bone graft (group 3). After 6 months, biopsies were obtained concurrent to the placement of dental implants; these were subjected to histomorphometric analysis and immunohistochemical analysis for runt-related transcription factor 2 (RUNX2) and vascular endothelial growth factor (VEGF). The average bone formation in group 1 was 46.3±11.6% in the pristine bone region, 47.6±9.9% in the intermediate region, and 44.8±22.1% in the apical region; in group 2, values were 35.0±15.8%, 32.5±13.7%, and 32.8±16.0%, respectively; in group 3, values were 43.1±16.0%, 31.0±13.0%, and 46.1±16.3%, respectively. Immunostaining of samples in group 2 showed high cellular activity and immature bone; this differed from groups 1 and 3, in which mature bone was demonstrated. Thus, this study showed that β-TCP presents the same behaviour as autogenous bone graft, which makes it a good bone substitute.

Magnetic Field Effects on Bone Repair after Calcium Phosphate Cement Implants: Histometric and Biochemistry Evaluation.

Objective:This work evaluated histologic and biochemically the effect of magnetic field buried in bone repair after autogenous bone graft and calcium phosphate cement implants.Methodology:Bone defects with 5,0 mm of diameter in the cranium of Wistar mice were used to analyse. These mice were submitted to different interventions: autogenous bone graft and calcium phosphate cement implants, both with and without magnetic stimulation. Longitudinal and transversal histometric and biochemistry analysis were made in times of 15, 30 and 60 post-operative days.Results:The histometric transversal analysis did not show significant differences in the bone repair between groups. Longitudinally, significant difference were found in the quantity of neoformed bone between the times 15 and 60 post-operative days in the autogenous bone graft group under magnetic stimulation. The alkaline phosphatase enzyme presented a higher activity in 30 post-operative days and the groups under magnetic stimulation presented reduced enzymatic activity in comparison to the other groups.Conclusion:The permanent and static magnetic field promoted significant differences in the neoformed bone in the groups autogenous bone graft.

Histological analysis and gene expression profile following augmentation of the anterior maxilla using rhBMP-2/ACS versus autogenous bone graft.

The objective of this report was to present histological characteristics and gene expression profile of newly formed bone following horizontal augmentation of the atrophic anterior maxilla using recombinant human bone morphogenetic protein-2 in an absorbable collagen sponge carrier (rhBMP-2/ACS) versus an autogenous bone graft (ABG). Bone core biopsies from 24 subjects participating in a randomized clinical trial were obtained at dental implant placement, 6months following alveolar ridge augmentation using rhBMP-2/ACS (rhBMP-2 at 1.5mg/ml; total dose 4.2mg) or a particulate ABG harvested from the mandibular retro-molar region. A titanium mesh was used to provide wound stability and space for bone formation. Analysis included histological/histometric observations and gene expression profile of the newly formed bone. rhBMP-2/ACS yielded bone marrow rich in capillaries, undifferentiated cells and bone lining cells compared with the ABG (p=0.002). Whereas no significant differences were observed in total bone fraction (p=0.53), non-vital bone particles trapped in lamellar vital bone were observed in the ABG group (p<0.001). Real-time PCR showed greater BMP-2 and RUNX2 expression for rhBMP-2/ACS over the ABG (p=0.001 and 0.0021, respectively), while the ABG exhibited greater expression of RANKL:OPG, BSP and OPN over rhBMP-2/ACS (p=0.01, 0.005 and 0.0009, respectively). Our observations suggest that formative biological processes explain bone formation following implantation of rhBMP-2/ACS, whereas remodelling, resorptive/formative processes, characterizes sites receiving ABGs.

Augmentative locking plate with autologous bone grafting for distal femoral nonunion subsequent to failed retrograde intramedullary nailing

ObjectiveTo explore the indications and efficacy of augmentative locking compression plate (LCP) or less invasive stabilization system (LISS)with autogenous bone grafting (BG) in treating distal femoral nonunion subsequent to failed retrograde intramedullary nailing (RIN). MethodsA retrospective study was performed for 21 patients with distal femoral nonunion subsequent to failed RIN, who received therapy with either augmentative LCP (n = 11) or LISS with autogenous BG (n = 13). Operation time, time to union, union rate, time to renonunion, complication rate and SF-36 scores a year after hardware removal were compared between the two groups. ResultsThe bone union occurred in 13/13 (100%) cases in augmentative LISS group versus 9/11 (81.8%) cases in augmentative LCP group [odds ratio (OR) = 3.21, 95% confidence interval (CI) 0.7–13]. Time to union, time to renonunion, complication rate of the augmentative LCP group were significantly more than that of the augmentative LISS with autogenous BG group (p = 0.023, p = 0.021 and p = 0.033). No significant difference was found in the average operation time of two groups (p = 0.121). At the follow-up a year after hardware removal, statistically significant HRQOL improvement in the augmentive LISS group was measured at the level of pain (p = 0.003) and general health perception (p = 0.011), as compared to the augmentive LCP group. ConclusionsWe suggest augmentative LCP, for distal femoral nonunios after RIN, may be optimal for that of typeAO33A fractures, whereas augmentative LISS for that of typeAO33C fractures more.

Evaluation of the osteogenesis and angiogenesis effects of erythropoietin and the efficacy of deproteinized bovine bone/recombinant human erythropoietin scaffold on bone defect repair.

Erythropoietin (EPO) could promote the angiogenesis and may also play a role in bone regeneration. This study was conducted to evaluate the osteogenesis and angiogenesis effects of EPO and the efficacy of deproteinized bovine bone/recombinant human EPO scaffold on bone defect repair. Twenty-four healthy adult goats were chosen to build goat defects model and randomly divided into four groups. The goats were treated with DBB/rhEPO scaffolds (group A), porous DBB scaffolds (group B), autogenous cancellous bone graft (group C), and nothing (group D). Animals were evaluated with radiological and histological methods at 4, 8 and 12 weeks after surgery. The grey value of radiographs was used to evaluate the healing of the defects and the outcome revealed that the group A had a better outcome of defect healing compared with group B (P < 0.05). However, the grey values in group A were lower than group C at week 4 and week 8 (P < 0.05), but at week 12 their difference had no statistical significance (P > 0.05). The newly formed bone area was calculated from histological sections and the results demonstrated that the amount of new bone in group A increased significantly compared with that in group B (P < 0.05) but was inferior to that in group C (P > 0.05) at 4, 8, 12 weeks respectively. In addition, the expression of vascular endothelial growth factor (VEGF) by immunohistochemical testing and real-time polymerase chain reaction at 12 weeks in group A was significantly higher than that in group B (P < 0.05), and also better than that in group C at week 4 and week 8 (P < 0.05), but at week 12 their difference had no statistical significance (P > 0.05). Therefore, EPO has significant effects on bone formation and angiogenesis, and has capacity to promote the repair of bone defects. It is worthy of being recommended to further studies.

Vertical Bone Augmentation Using Bone Marrow-Derived Stem Cells: An In Vivo Study in the Rabbit Calvaria.

To evaluate the bone regeneration capacity of bone marrow-derived stem cells (BMSCs) in vertical guided augmentation of bone tissue. The calvaria of 20 rabbits were vertically augmented with autogenous bone graft (ABG); collagen/beta-tricalcium phosphate (β-TCP) linked scaffold transplanted with 15 × 10 BMSCs; or scaffold alone (control). The augmentation materials were covered with stainless steel domes. BMSCs were isolated with Ficoll-Paque technique and applied directly without in vitro expansion. The newly formed bone was evaluated using radiodensitometric, histomorphometric, histological, and micro-computed tomographic (micro-CT) analyses after a 12-week healing period. The data excluding micro-CT assessments were compared statistically. Radiodensitometric and bone volume parameters demonstrated increased bone formation in both BMSC group and ABG group compared with control group (P < 0.01), but difference between the BMSC and ABG groups was not significant (P > 0.05). The mean histological scores for the BMSC, ABG, and control groups were 7.44 ± 1.03, 8.44 ± 0.81, and 6.00 ± 1.10, respectively, indicating significant difference among the groups (P < 0.05). BMSCs delivered with a collagen/β-TCP linked scaffold can provide improved new bone formation that is comparable with autogenous bone block graft through vertical guided bone regeneration technique.