• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권3호
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• pp.161-171
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• 2010

Introduction: This study was to assess the effectiveness of new bone formation and regeneration by using a rhBMP-2 and $\beta-TCP$ as a carrier in rabbits’mandible. Materials and Methods: The mandibles of 36 rabbits were exposed and cortical bone was penetrated for this study. The experimental subjects were divided into 3 groups each 12 rabbits ; control group, experimental group 1, and experimental group 2. Control group had the defect itself without any treatment, in the experimental group 1, $\beta-TCP$P only was grafted, and in the experimental group 2, rhBMP-2 soaked in $\beta-TCP$ was grafted. The rabbits were sacrificed after 1, 2, 3, 4, 6, and 8weeks, and new bone formation area was examined and measured for bone quantitative and qualitative analysis with light, fluorescent and polarized microscopy. Results: In the experimental group 1, new bone formation from the adjacent host bone was made by osteoconduction, and in the experimental group 2, direct new bone formation by osteoinduction of rhBMP-2 as well as new bone formation by osteoconduction of $\beta-TCP$ were observed. Conclusion: rhBMP-2 of experimental group 2 is very effective in the bone formation in early 2weeks and bone remodelling from 3weeks.

• The Korean Journal of Physiology and Pharmacology
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• 제3권6호
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• pp.539-546
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• 1999

Bone is a complex tissue in which resorption and formation continue throughout life. The bone tissue contains various types of cells, of which the bone forming osteoblasts and bone resorbing osteoclasts are mainly responsible for bone remodeling. Periodontal disease represents example of abnormal bone remodeling. Osteoclasts are multinucleated cells present only in bone. It is believed that osteoclast progenitors are hematopoietic origin, and they are recruited from hematopoietic tissues such as bone marrow and circulating blood to bone. Cells present in the osteoclast microenvironment include marrow stromal cells, osteoblasts, macrophages, T-lymphocytes, and marrow cells. These cells produce cytokines that can affect osteoclast formation. In vitro model systems using bone marrow cultures have demonstrated that $IL-l{\beta},\;IL-3,\;TNF-{\alpha},$ bFGF can stimulate the formation of osteoclasts. In contrast, IL-4 inhibits osteoclast formation. Knowledge of cytokines and bFGF that affect osteoclast formation and their capacity to modulate the bone-resorbing process should provide critical insights into normal calcium homeostasis and disorders of bone turnover such as periodontal disease, osteoporosis and Paget's disease.

• 대한수의학회지
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• 제45권2호
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• pp.273-278
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• 2005

This study was investigated of the bone healing capacity by autologous fibrin glue in experimental bone defect dogs. The autologous fibrin glue manufactured just before the experiment was mixed with the concentrated fibrinogen from whole blood of the experimental dog and bovine thrombin. The experimental group was constituted with seven dogs. The experimental osteotomy was performed 5 mm length in bilateral region of proximal diaphyseal fibulae. The defected regions of experimental group were filled with the autologous fibrin glue by duploject. The experimental regions had been radiographed biweekly for 16 weeks to observe new bone formation and union. Bone alkaline phophatase (BALP) in all groups was evaluated biweekly till the end of the experiment to determine osteoblast activities. New bone formation had been observed in five regions of three dogs at four weeks after the experimental treatment and in two regions of one dog at ten weeks. The other seven regions of the experimental group and control group were not observed new bone formation until the end of the experiment. BALP value in four dogs observed new bone formation was increased to 97.10 IU/L (453.96%) at two weeks after the experimental treatment. The results of this experiment were suggested that the autologous fibrin glue was moderately effective in new bone formation in dogs.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권3호
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• pp.239-252
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• 1995

The present study was aimed to evaluate the effect of demineralized freeze-dried bone (DFDB) and resorbable hydroxyapatite (RHA) on bone formation in the extracted socket. The lower left and right 2nd and 3rd premolar were extracted in adult dogs. The one group was grafted with DFDB into the extracted socket, and the other group grafted with RHA. The extracted socket was sutured without any graft materials as control. The animals were killed on the 1st, 2nd, 4th, and 8th week after the graft for macroscopic and microscopic examination. Results obtained were as follows : 1. Macroscopically, nor infection of the graft site and dislodgement of the grafted material were noted in any animals used. 2. Young trabeculae of osteoid were formed in the socket wall in control group at 2 weeks after the graft. Osteoid tissue was formed in DFDB group at 1 week after graft, and a fine osteoid tissue was grown through the RHA particles in RHA group at 2 weeks graft. 3. The grafted groups showed more rapid bone formation than the control. Between the grafted groups, DFDB group showed more rapid formation than RHA group, DFDB group showed osteoinductive bone formation and RHA group showed osteoconductive bone formation. These results suggest that DFDB and RHA are useful to preserve the alveolar bone and to improve new bone formation by immediate grafting into the extraction sockets.

• The Journal of Advanced Prosthodontics
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• 제10권3호
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• pp.167-176
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• 2018

PURPOSE. The purpose of this study was to compare the new bone formation capability of zirconia with those of other synthetic bone grafts. MATERIALS AND METHODS. Twelve rabbits were used and four 6-mm diameter transcortical defects were formed on each calvaria. Each defect was filled with Osteon II (Os), Tigran PTG (Ti), and zirconia (Zi) bone grafts. For the control group, the defects were left unfilled. The rabbits were sacrificed at 2, 4, and 8 weeks. Specimens were analyzed through micro computed tomography (CT) and histomorphometric analysis. RESULTS. The Ti and Zi groups showed significant differences in the amount of newly formed bone between 2 and 4 weeks and between 2 and 8 weeks (P<.05). The measurements of total bone using micro CT showed significant differences between the Os and Ti groups and between the Os and Zi groups at 2 and 8 weeks (P<.05). Comparing by week in each group, the Ti group showed a significant difference between 4 and 8 weeks. Histomorphometric analysis also showed significant differences in new bone formation between the control group and the experimental groups at 2, 4, and 8 weeks (P<.05). In the comparison of newly formed bone, significant differences were observed between 2 and 4 weeks and between 2 and 8 weeks (P<.05) in all groups. CONCLUSION. Zirconia bone graft material showed satisfactory results in new bone formation and zirconia could be used as a new synthetic bone graft material.

• Journal of Microbiology and Biotechnology
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• 제18권5호
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• pp.975-982
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• 2008

We investigated whether transplantation of osteogenically differentiated bone marrow-derived mesenchymal stem cells (BMMSCs) and the use of an hydroxyapatite (HAp) scaffold can enhance the in vivo bone formation efficacy of human BMMSCs. Three months after implantation to the subcutaneous dorsum of athymic mice, transplantation of osteogenically differentiated human BMMSCs increased the bone formation area and calcium deposition to 7.1- and 6.2-folds, respectively, of those of transplantation of undifferentiated BMMSCs. The use of the HAp scaffold increased the bone formation area and calcium deposition to 3.7- and 3.5-folds, respectively, of those of a polymer scaffold. Moreover, a combination of transplantation of osteogenically differentiated BMMSCs and HAp scaffold further increased the bone formation area and calcium deposition to 10.6- and 9.3-folds, respectively, of those of transplantation of undifferentiated BMMSCs seeded onto polymer scaffolds. The factorial experimental analysis showed that osteogenic differentiation of BMMSCs prior to transplantation has a stronger positive effect than the HAp scaffold on in vivo bone formation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.34.1-34.7
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• 2020

Purpose: The purpose of this study was to evaluate the influence of biodegradable polycaprolactone membrane on new bone formation and the biodegradation of biphasic alloplastic bone substitutes using animal models. Materials and methods: In this study, bony defect was formed at the canine mandible of 8 mm in diameter, and the defects were filled with Osteon II. The experimental groups were covered with Osteoguide as barrier membrane, and the control groups were closed without membrane coverage. The proportion of new bone and residual bone graft material was measured histologically and histomorphometrically at postoperative 4 and 8 weeks. Results: At 4 weeks, the new bone proportion was similar between the groups. The proportion of remaining graft volume was 27.58 ± 6.26 and 20.01 ± 4.68% on control and experimental groups, respectively (P < 0.05). There was no significant difference between the two groups in new bone formation and the amount of residual bone graft material at 8 weeks. Conclusion: The biopolymer membrane contributes to early biodegradation of biphasic bone substitutes in the jaw defect but it does not affect the bone formation capacity of the bone graft.

• Journal of Periodontal and Implant Science
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• 제38권sup2호
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• pp.355-362
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• 2008

Purpose: The carrier for the delivery of bone morphogenetic proteins(BMPs) should also serve as a scaffold for new bone growth. In addition, predictable bone formation in terms of the volume and shape should be guaranteed. This study evaluated the ectopic bone formation of recombinant human BMP-2(rhBMP-2) using a micro macroporous biphasic calcium phosphate (MBCP: mixture of ${\beta}TCP$ and HA) block as a carrier in a rat subcutaneous assay model. Materials and Methods: Subcutaneous pockets were created on the back of 40 male Sprague-Dawley rats. In the pockets, rhBMP-2/MBCP and MBCP alone were implanted. The blocks were evaluated by histological and histometric parameters after a healing interval of 2 weeks (each 10 rats; MBCP and rhBMP-2/MBCP) or 8 weeks (each 10 rats; MBCP and rhBMP-2/MBCP). Results: The shape and volume of the block was maintained stable over the healing period. No histological bone forming activity was observed in the MBCP alone sites after 2 weeks and there was minimal new bone formation at 8 weeks. In the rhBMP-2/MBCP sites, new bone formation was evident in the macropores of the block. The new bone area at 8 weeks was greater than at 2 weeks. There was a further increase in the quantity of new bone with the more advanced stage of remodeling. Conclusions: A MBCP block could serve as a carrier system for predictable bone tissue engineering using rhBMPs.

• BMB Reports
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• 제51권6호
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• pp.263-264
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• 2018

We identified osteoclast-derived SLIT3 as a new coupling factor using fractionated secretomics. Coupling links bone resorption to bone formation. SLIT3 stimulated the recruitment and proliferation of osteoblasts into bone remodeling sites via activation of ${\beta}-catenin$. Autocrine signaling by SLIT3 also inhibited bone resorption by suppressing the fusion and differentiation of pre-osteoclasts. All mice lacking Slit3 or its receptor Robo1 showed an osteopenic phenotype with low bone formation and high bone resorption. A small truncated recombinant SLIT3 protein increased bone mass in an osteopenic mouse model. These results suggest that SLIT3 is a novel therapeutic target in metabolic bone diseases.

• Biomolecules & Therapeutics
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• 제11권2호
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• pp.81-84
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• 2003

Recently, diabetes has been found to be associated with osteoporosis. Specially in IDDM. In both type I and type II diabetes, glucose levels are elevated. Thus, a linkage between high glucose and osteoporosis can not be ruled out. In this study, an attempt has been made to observe the effect of high glucose on bone formation; osteoblast like UMR 106 cells were treated with high glucose (22 mM, 33 mM) for 1, 3 or 7 days. The high concentration of glucose inhibited markers. of bone formation activity such as alkaline phosphatase and collagen synthesis. In addition, reduction in the level of total cellular protein in response to high glucose was also observed. This study showed high glucose concentration could alter the bone metabolism leading to a defective bone formation and thus paving the linkage of such situation to diabetic complications.