Rabbit Calvaria Research Articles

Vertical Guided Bone Regeneration in the Rabbit Calvarium Using Porous Nanohydroxyapatite Block Grafts Coated with rhVEGF165 and Cortical Perforation.

IntroductionVertical bone augmentation without osseous walls to support the stability of clots and bone grafts remains a challenge in dental implantology. The objectives of this study were to confirm that cortical perforation of the recipient bed is necessary and to evaluate whether nanohydroxyapatite (nHA) block grafts coated with recombinant human vascular endothelial growth factor165 (rhVEGF165) and cortical perforation can improve vertical bone regeneration.Materials and MethodsWe prepared nHA blocks coated with or without rhVEGF165 on the rabbit calvarium through cortical perforation, and designated the animals as the nonperforated group (N-nHA), rhVEGF165 group (NV-nHA), perforated group (P-nHA) and rhVEGF165 on perforated group (PV-nHA). Micro-computed tomography (micro-CT) and fluorescence microscopy were selected to evaluate parameters of vertical bone regeneration at 4 and 6 weeks.ResultsThe ratio of the newly formed bone volume to the titanium dome volume (BV/TV) and the bone mineral density (BMD) were significantly higher in the PV-nHA group than in the N-nHA group at 4 and 6 weeks, as determined using micro-CT. The fluorescence analysis showed slightly greater increases in new bone regeneration (NB%) and vertical height (VH%) gains in the P-nHA group than in the N-nHA group. Greater increases in NB% and VH% were observed in groups treated with rhVEGF165 and perforation than in the blank groups, with significant differences detected at 4 and 6 weeks (N-nHA compared with PV-nHA, p<0.05). A greater VH% that was observed at the midline of the block in the PV-nHA group than in the other three groups at both time points (0.75±0.53% at 4 weeks and 0.83±0.42% at 6 weeks).ConclusionAccording to the present study, cortical perforation is necessary and nHA blocks coated with rhVEGF165 and decoration could work synergistically to improve vertical bone regeneration by directly affecting primary osteoblasts and promoting angiogenesis and osteoinduction.

Application of a New Type of Natural Calcined Bone Repair Material Combined with Concentrated Growth Factors in Bone Regeneration in Rabbit Critical-Sized Calvarial Defect.

Purpose This study is aimed at investigating bone regeneration in critical-sized defects in rabbit calvarium using a novel nano- (n-) hydroxyapatite hybrid scaffold with concentrated growth factors (CGFs). Methods Twenty-four male adult rabbits were chosen to establish a critical-sized bone defect model and randomly divided into two groups. Two defects of 15 mm diameter each were created in the parietal bone of each animal. Group A had n-hydroxyapatite hybrid scaffold placed in the experimental defect on the right, and the left defect was unfilled as blank. Group B had hydroxyapatite hybrid scaffold mixed with CGF placed in the right defect and CGF on the left. Six animals in each group were sacrificed after 6 and 12 weeks. Cone-beam computed tomography system scanning and hematoxylin and eosin (HE) staining were used to detect osteogenesis within the defects. Results The treatment with n-hydroxyapatite hybrid scaffold along with CGF resulted in a significantly higher amount of new bone at 6 and 12 weeks compared to the treatment with CGF alone and the controls. No apparent inflammation and foreign body reaction were observed through HE staining. Conclusions The new synthesized n-hydroxyapatite hybrid scaffold and CGF can be applied for bone defect regeneration to promote the process to a certain extent.

The Impact of Compaction Force on Graft Consolidation in a Guided Bone Regeneration Model.

Compaction of particulated grafts is done manually; thus, the effect of compression force on bone regeneration remains unclear. The aim of this study was to evaluate the impact of two different compression forces on the consolidation of particulated bovine hydroxyapatite. Two titanium cylinders were fixed on the calvarium of eight New Zealand rabbits. Both defects were filled with particulated bovine hydroxyapatite subjected to a compression force of 0.7 kg/cm2 or 1.6 kg/cm2 before being covered with a resorbable collagen membrane. A handheld device that uses a spring to control the compression force applied by the plugger was used. At 6 weeks, histomorphometry of the area immediately adjacent to the calvaria bone and to the collagen membrane was performed. It was shown that next to the calvaria, the bone volume per tissue volume (BV/TV) was 29.0% ± 8.8% and 27.6% ± 8.2% at low and high compression force, respectively; the bone-to-biomaterial contact (BBC) was 58.2% ± 25.0% and 69.3% ± 22.9%, respectively (P > .05). In the corresponding area next to the collagen membrane, BV/TV was 4.9% ± 5.1% and 5.7% ± 4.7%, and the BBC was 18.3% ± 20.8% and 20.1% ± 15.9%, respectively (P > .05). In addition, the number and area of blood vessels were not significantly affected by compression force. Both compression forces applied resulted in similar consolidation of bovine hydroxyapatite expressed by new bone formation and vascularization based on a rabbit calvaria augmentation model.

The Effect of Atmospheric Pressure Cold Plasma Application on Titanium Barriers: A Vertical Bone Augmentation.

The aim of the present, microcomputed tomographic (μCT) and histological study, was to evaluate the effect of surface modification by atmospheric pressure cold plasma (APCP) on vertical guided bone regeneration in a rabbit calvaria model. The experimental study was conducted on 12 male New Zealand rabbits with healing periods of 45 and 90 days. Following surgical exposure of the calvarium, 4 customized titanium cylindricalders were fixed. Surface modification was achieved by application of APCP on 2 of cylinders (P+) in each calvarium and other cylinders were set as control (P-). In both experimental and control groups, one of the cylinders was filled with bone graft (G+) while the other one was left empty (G-). To evaluate short term effects, randomly selected 6 animals were sacrificed at the end of 45 days and remaining 6 animals were left for observing long term effects. Histological and μCT evaluations were used to examine new bone formation. In μCT imaging; the bone volume was greater (P < 0.05) in grafted groups than nongrafted groups in both short and long term. The bone height values were significantly different in (P-G-) group than other groups (P < 0.05) in both evaluation periods. The histological evaluations revealed significant differences between P+G+ group and other groups but in long term both plasma treated groups revealed more bone formation than non plasma treated groups. Modification of the surfaces of titanium cylinders by APCP treatment, accelerated the bone regeneration either bone graft used or not in a rabbit calvaria model.

Comparative Evaluation of Bone Repair with Four Different Bone Substitutes in Critical Size Defects

This study evaluated the osteoconductive potential of four biomaterials used to fill bone defects. For this, 24 male Albino rabbits were submitted to the creation of a bilateral 8 mm calvarial bone defect. The animals were divided into four groups—bovine hydroxyapatite, Bio-Oss® (BIO); Lumina-Bone Porous® (LBP); Bonefill® (BFL); and an alloplastic material, Clonos® (CLN)—and were euthanized at 14 and 40 days. The samples were subjected to histological and histometric analysis for newly formed bone area. Immunohistochemical analysis for Runt-related transcription factor 2 (Runx2), vascular endothelial growth factor (VEGF), and osteocalcin (OC) was performed. After statistical analysis, the CLN group showed greater new bone formation (NB) in both periods analyzed (p < 0.05). At 14 days, the NB showed greater values in BIO in relation to LBP and BFL groups; however, after 40 days, the LBP group surpassed the results of BIO (p < 0.001). The immunostaining showed a decrease in Runx2 intensity in BIO after 40 days, while it increased for LBP (p < 0.05). The CLN showed increased OC compared to the other groups in both periods analyzed (p < 0.05). Therefore, CLN showed the best osteoconductive behavior in critical defects in rabbit calvaria, and BFL showed the lowest osteoconductive property.

Synergism between recombinant human bone morphogenetic protein 2/absorbable collagen sponge and bone substitutes favors vertical bone augmentation and the resorption rate of the biomaterials: Histomorphometric and 3D microcomputed tomography analysis.

Recombinant human bone morphogenetic protein 2 (rhBMP-2) is an osteoinductor frequently used for bone regeneration in oral and maxillofacial surgery. There is no consensus about the ideal carrier for this growth factor. The aim of this study was to compare the bone augmentation, bone microarchitecture, and biodegradation rate of additional carriers to rhBMP-2/absorbable collagen sponge (ACS) in a vertical guided bone regeneration model. Four titanium cylinders were fixed onto the calvaria of rabbits (n=20) that received (n=10) or not (n=10) rhBMP-2/ACS in conjunction with one of the carriers: beta-tricalcium phosphate (β-TCP), biphasic calcium phosphate (BCP), bovine bone mineral (BBM) or blood clot. The samples were analyzed by means of microcomputed tomography and histomorphology after 14weeks. All the materials with rhBMP-2/ACS exhibited improvement on bone augmentation, mainly BCP (P=0.033) and β-TCP (P=0.038), in the upper portion of the cylinder. Although trabecular anisotropy was improved in all the materials groups, trabecular connectivity was diminished when the biomaterials received rhBMP-2/ACS. Resorption rate of the remaining biomaterial was improved by rhBMP-2/ACS, mainly in BBM (P<0.01) and β-TCP (P<0.01). BBM exhibited the highest osteoclast density compared with the other materials groups. BCP and β-TCP biomaterials exhibited a synergic effect with rhBMP-2/ACS, acting as suitable and viable carriers for vertical bone augmentation. The addition of rhBMP-2 significantly affected the biodegradation of β-TCP and BBM, accelerating the resorption of these materials.

Effect of Gellan Gum/Tuna Skin Film in Guided Bone Regeneration in Artificial Bone Defect in Rabbit Calvaria.

It is necessary to prevent the invasion of soft tissue into bone defects for successful outcomes in guided bone regeneration (GBR). For this reason, many materials are used as protective barriers to bone defects. In this study, a gellan gum/tuna skin gelatin (GEL/TSG) film was prepared, and its effectiveness in bone regeneration was evaluated. The film exhibited average cell viability in vitro. Experimental bone defects were prepared in rabbit calvaria, and a bone graft procedure with beta-tricalcium phosphate was done. The film was used as a membrane of GBR and compared with results using a commercial collagen membrane. Grafted material did not show dispersion outside of bone defects and the film did not collapse into the bone defect. New bone formation was comparable to that using the collagen membrane. These results suggest that the GEL/TSG film could be used as a membrane for GBR.

Histomorphometric Comparison of 2 types of FDBA and DFDBA bone powders manufactured by Faravardehaye Peyvandi Iran Company in treatment of defects in rabbit calvaria bone

Histomorphometric Comparison of 2 types of FDBA and DFDBA bone powders manufactured by Faravardehaye Peyvandi Iran Company in treatment of defects in rabbit calvaria bone

Bone Formation in Grafts with Bio-Oss and Autogenous Bone at Different Proportions in Rabbit Calvaria.

Background The aim of this study was to assess the volumetric stability and bone formation in grafts with Bio-Oss and autogenous bone at different proportions in rabbit calvaria. Material and Methods. Ten rabbits received four titanium cylinders in their calvaria and randomly divided into the following groups: Group I: Bio-Oss (100%), Group II: Bio-Oss (75%) + autogenous bone (25%), Group III: Bio-Oss (50%) + autogenous bone (50%), and Group IV: autogenous bone (100%). After twelve weeks, the animals were euthanized, and samples were collected for clinical and histological analysis. Results Clinical analysis showed that Groups I (90.43 ± 8.99) and II (90.87 ± 7.43) had greater dimensional stability compared to Group IV (P=0.0005). Histologically, Groups I, II, and III showed areas of bone formation with particles of biomaterial remaining in close contact with the newly formed bone. However, there were no significant differences between the groups regarding the newly formed bone area. Conclusion It was concluded that the use of Bio-Oss either alone or associated with the autogenous bone at a proportion of 25% showed superior dimensional stability compared to the use of autogenous bone in the proposed experimental model.

Effects of additional collagen in biphasic calcium phosphates: a study in a rabbit calvaria.

Biphasic calcium phosphates (BCP) are synthetic biomaterials developed as an alternative to the autogenous bone grafts and xenografts. The aim of the present study was to assess the influence of the addition of collagen onto the BCP resorption rate and bone formation. Eighteen male NWZ rabbits approximately 12weeks of age were used. Critical size defects were randomly treated with bilayered BCP materials comprising 12% HA and 88% α-TCP with and without collagen or sham-operated, respectively. All defects were covered with a resorbable collagen membrane. Animals were euthanized after 3 and 12weeks of healing and investigated by micro-CT, histologic, and histomorphometric analysis. Woven bone formation was observed from the original bone at 3-week healing in all samples. After 3months, mainly lamellar new bone in the peripheral area was observed. In the central region, both woven and lamellar bone were seen. Samples containing collagen showed less residual biomaterial than without collagen at both healing periods. Both types of granules were in close contact with new bone, yielding a complete defect closure at 3months of healing. However, new bone volume and area was similar for both biomaterials. Within its limitations, the study results qualify collagen as a biocompatible carrier for BCPs. The presence of collagen indicated neither significant impact on the resorption of the BCPs nor on bone formation. The addition of collagen to BCPs might not be beneficial for the augmentation of extended bone deficiencies.

Porcine Collagen-Bone Composite Induced Osteoblast Differentiation and Bone Regeneration In Vitro and In Vivo.

Due to autogenous bone limitations, some substitute bone grafts were developed. Collagenated porcine graft (CPG) is able to regenerate new bone, although the number of studies is insufficient, highlighting the need for future studies to better understand the biomaterial. In order to understand better CPG′s possible dental guided bone regeneration indications, the aim of this work was to determine CPG′s biological capacity to induce osteoblast differentiation in vitro and guided bone regeneration in vivo, whilst being compared with commercial hydroxyapatite and beta tricalcium phosphate (HA/β-TCP) and porcine graft alone. Cell cytotoxicity (WST-1), alkaline phosphatase activity (ALP), and real-time polymerase chain reaction (qPCR) were assessed in vitro. Critical size defects of New Zealand white rabbits were used for the in vivo part, with critical size defect closures and histological analyses. WST-1 and ALP indicated that CPG directly stimulated a greater proliferation and confluency of cells with osteoblastic differentiation in vitro. Gene sequencing indicated stable bone formation markers, decreased resorption makers, and bone remodeling coupling factors, making the transition from osteoclast to osteoblast expression at the end of seven days. CPG resulted in the highest new bone regeneration by osteoconduction in critical size defects of rabbit calvaria at eight weeks. Nonetheless, all biomaterials achieved nearly complete calvaria defect closure. CPG was found to be osteoconductive, like porcine graft and HA/β-TCP, but with higher new bone formation in critical size defects of rabbit calvaria at eight weeks. CPG can be used for different dental guided bone regeneration procedures; however, further studies are necessary.

Bone-implant-contact and new bone formation around implants placed in FDB blocks compared to placement at the adjunction of particulate FDB.

The efficacy of human freeze-dried bone (h-FDB) as particulate vs block forms as a proper onlay augmented bone graft material to accommodate implants is undetermined. To evaluate osseointegration and new bone formation at implants placed in FDB blocks (BL group) and those at the adjunction of particulate FDB (PR group). Twelve pairs of h-FDB blocks were stabilized bilaterally to the calvaria of 12 rabbits. Twenty-four SLA implants were placed at the remodeled grafted blocks, 4 months later. A circumferential gap was created around one implant in each pair and packed with particulate h-FDB. Section biopsies were obtained at 2-month post implant placement (6 months post-block grafting). Bone-to-implant contact (BIC) and bone-area fraction (BAF) were histomorphometrically calculated. The mean BIC was 34.4% and 33.5% for the BL and PR groups, respectively. The mean BAF was 23.9% and 26.4% for the corresponding groups, respectively. Osseointegration and newly formed bone were evident mostly between the threaded portions of the implants in proximity to the host rabbit calvaria compared to its cervical neck. The particulate and the cancellous block h-FDB forms yielded similar BIC and BAF outcome. Full revascularization/revitalization is questioned.

Bone Marrow Stem Cells in Appositional Bone Construction: A Pilot Study in Rabbit Calvaria

Bone Marrow Stem Cells in Appositional Bone Construction: A Pilot Study in Rabbit Calvaria

Comparative Histomorphometric Evaluation of Bone Regeneration with Different Preparations of Xenogeneic Tooth Block Bone.

The aim of this animal study was to evaluate new bone formation in human dentin block grafted on rabbit calvaria according to a comparison of histologic analysis. Human teeth were prepared according to four different types of dentin blocks: group 1, demineralized and microperforated dentin block; group 2, demineralized dentin block; group 3, undemineralized and microperforated dentin block; group 4, undemineralized dentin block. These four different dentin blocks were grafted on nine rabbit calvaria, and animals were sacrificed at 2, 4, and 8 weeks after the surgical procedure for histologic evaluation. In group 1, histologically, new bone formation was initiated at the interface between demineralized and microperforated dentin block and host bone and microholes at 2 weeks, and mature bone was observed at 8 weeks. In group 3, new bone formation was observed at 8 weeks in the undemineralized and microperforated dentin block bottom and microholes. The bone formation ratio of group 1 was significantly higher at 2, 4, and 8 weeks compared with groups 2, 3, and 4 (P < .05). The bone formation ratio in microholes at 2 and 8 weeks in group 1 was significantly greater than in group 3 (P < .05). New bone formation of the demineralized dentin block began more rapidly than the undemineralized dentin block, and perforated dentin block was more effective in bone formation than dentin block without microholes.

Histologic Evaluation of the Bone Regeneration Capacities of Bio-Oss and MinerOss X in Rabbit Calvarial Defects.

Several methods are used for periodontal regeneration and alveolar ridge reconstruction. This study aimed to compare the bone regeneration capacities of MinerOss X, Bio-Oss, and autograft in rabbit calvaria. In this animal study, four defects measuring 8 mm in diameter were created in the calvaria of 10 rabbits using a trephine bur. Three defects were randomly filled with MinerOss X, Bio-Oss, and autogenous bone. The fourth defect remained empty as a control. The rabbits were sacrificed after 4 or 8 weeks. Calvarial samples were taken and histopathologically evaluated. The mean number of osteoblasts and the amount of newly formed bone in all groups were higher at 8 compared to 4 weeks. At 4 and 8 weeks, the amount of newly formed bone and number of osteoblasts and osteocytes in MinerOss X group were significantly greater than the corresponding values in other groups, and MinerOss X was superior to Bio-Oss and autograft in all the assessed variables at both 4 and 8 weeks (P < .001). Within the limitations of this study, the results showed that the number of osteoblasts and osteocytes and the amount of newly formed bone in the MinerOss X group were higher than those in Bio-Oss and autograft groups. However, further clinical studies are warranted.

Use of Platelet-Rich Fibrin Associated with Xenograft in Critical Bone Defects: Histomorphometric Study in Rabbits

Platelet-rich fibrin (PRF) is an autologous material used to improve bone regeneration when associated with bone grafts. It affects tissue angiogenesis, increasing the healing process and, theoretically, presenting potential to increase bone neoformation. The aim of this study was to verify, histomorphometrically, the effects of the association of PRF to a xenograft. Twelve adult white New Zealand rabbits were randomly assigned into two groups containing six animals each. After general anesthesia of the animals, two critical defects of 12 mm were created in the rabbit calvaria, one on each side of the sagittal line. Each defect was filled with the following biomaterials: in the control group (CG), xenograft hydrated with saline solution filling one defect and xenograft hydrated with saline solution covered with collagen membrane on the other side; in the test group (TG), xenograft associated with PRF filling the defect of one side and xenograft associated with PRF covered with collagen membrane on the other side. After eight weeks the animals were euthanized and a histomorphometric analysis was performed. The results showed that in the sites that were covered with collagen membrane, there was no statistically significant difference for all the analyzed parameters. However, when comparing the groups without membrane coverage, a statistically significant difference could be observed for the vital mineralized tissue (VMT) and nonmineralized tissue (NMT) parameters, with more VMT in the test group and more NMT in the control group. Regarding the intragroup comparison, the use of the membrane coverage presented significant outcomes in both groups. Therefore, in this experimental model, PRF did not affect the levels of bone formation when a membrane coverage technique was used. However, higher levels of bone formation were observed in the test group when membrane coverage was not used.

Bone augmentation using small molecules with biodegradable calcium sulfate particles in a vertical onlay graft model in the rabbit calvarium.

Small molecules including sodium butyrate (SB) and dimethyloxalylglycine (DMOG) can promote bone regeneration via inhibitive effects eliciting cellular responses through signaling cascades. The purpose of this study was to determine the synergistic effects of SB and DMOG loaded on calcium sulfate (CaS) on bone regeneration in the challenging vertical augmentation model in the rabbit calvarium. Four plastic cylinders screwed on the calvarium of each of 10 rabbits were randomly grafted with CaS, CaS/SB, CaS/DMOG, or CaS/DMOG/SB. All specimens were assessed by radiographic, histologic, and histomorphometric analyses. In the radiographic analysis, three different layers (new bone, degraded CaS, and pristine CaS layers) could be distinguished within the cylinder in all groups at 2 weeks. Newly formed bone grew up from basal bone, and CaS in contact with newly formed bone was degraded into small particles to form a different layer. At 8 weeks, most of the pristine CaS had been absorbed and hardly seen within the cylinder. In the histomorphometric analysis, all groups showed comparable new bone areas and heights at 2 and 8 weeks. The DMOG group showed a significant increase in new bone area at 8 weeks compared with 2 weeks, but there was no significant difference among the groups at 8 weeks. The DMOG group showed significantly lower values for the residual material area than the control group at 2 weeks. Within the limitations of this study, SB and DMOG seem to exert smaller synergistic effects on bone regeneration compared to CaS alone in vertical bone augmentation.

Histological and Histomorphometric Analyses of Two Bovine Bone Blocks Implanted in Rabbit Calvaria

This study compared the osteogenic potential of two types of bovine bone blocks. Blocks were obtained by either sintered or a nonsintered process. Calvaria were surgically exposed in 20 rabbits. In each animal, six 0.5-mm-diameter cortical microperforations were drilled with a carbide bur before grafting to promote graft irrigation. The sintered (group 1) and nonsintered (group 2) bovine bone blocks (6 mm diameter, 5 mm high) were bilaterally screwed onto calvarial bone. Blocks were previously prepared from a larger block using a trephine bur. Rabbits were sacrificed after 6 and 8 weeks for the histological and histomorphometric analyses. Samples were processed using the historesin technique. The quantitative and qualitative analyses of the newly formed bone were undertaken using light microscopy. Both groups showed modest new bone formation and remodeling. At the 8-week follow-up, the sintered group displayed significantly lower bone resorption (average of 10% in group 1 and 25% in group 2) and neo-formation (12.86 ± 1.52%) compared to the nonsintered group (16.10 ± 1.29%) at both follow-ups (p &lt; 0.05). One limitation of the present animal model is that the study demonstrates that variations in the physico-chemical properties of the bone substitute material clearly influence the in vivo behavior.

Comparison of Different Bone Filling Materials and Resorbable Membranes by Means of Micro-Tomography. A Preliminary Study in Rabbits.

The purpose of this work was to evaluate the behavior of different membranes and bone filling materials used to fill critical defects in rabbit calvaria. Four defects were prepared in the cranial calvaria of female rabbits. They were randomly divided into three subgroups according to the type of barrier membrane to be used. Four animals carried cross-linked bovine collagen membranes (Mem-Lok, Bio-Horizons, Birmingham, AL, USA)), four human fascia lata membranes (Tissue, Inbiomed SA, Córdoba, Argentina) and four human chorioamniotic membranes (Tissue. Inbiomed SA, Córdoba, Argentina). The defects were filled with the deproteinized bovine bone particulate Bio­Oss® (Geistlich­Pharma AG, Wolhusen, Switzerland), with particulate human hydroxyapatite MinerOss® (Bio-Horizons, Birmingham, AL, USA), with particulate dental material (Tissue Bank Foundation, Inbiomed S.A., Córdoba, Argentina), and the last one was left without the addition of filler material. In the first group of four specimens, a resorbable cross-linked bovine collagen membrane was placed over the skull and defects, without additional fixing. In the second group, a human fascia lata membrane was placed, without additional fixing. In the third group, a human chorioamniotic membrane was placed, without additional fixing. The animals were sacrificed at 4 and 8 weeks. The highest percentages of relative radiological density (average) were recorded considering the amnio-chorionic membranes (83.63%) followed by collagen (81.44%) and finally the fascia lata membranes (80.63%), but the differences were not statistically significant (p > 0.05). The sites grafted with a decellularized tooth (96.83%) and Bio­Oss (88.42%), recorded the highest percentages of radiological density but did not differ significantly from each other (subset 2). The three membranes used did not show statistical differences between them, in any of the two time periods used. There were statistical differences between the filling materials evidencing the presence of a large quantity of calcified material in the defects treated with particulate tooth and deproteinized bovine bone and while smaller amounts of calcified material were registered in the case of defects treated with human hydroxyapatite and those that were not treated.

Histomorphometric Comparison of 2 types of FDBA and DFDBA bone powders manufactured by Hamanand Saz Baft Kish Company in treatment of defects in rabbit calvaria bone

Histomorphometric Comparison of 2 types of FDBA and DFDBA bone powders manufactured by Hamanand Saz Baft Kish Company in treatment of defects in rabbit calvaria bone