• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.573-584
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• 2003

Bone remodeling results from the combined process of bone resorption and new bone formation which is regulated in part by some of Dexamethasone related proliferation & mineralization of cultured bone cell and polypeptide growth factors such as platelet derived growth factor(PDGF), which has been known to be an important local regulator of bone cell activity and participate in normal bone remodeling. To evaluate the effects of Dex and PDGF on bony healing of calvarial defect in rats, 10 ng/ml PDGF were applied on P group and 10 ng/ml PDGF and $10^7$ M Dex were applied PD group. 4 rats in each group were sacrificed at 7, 14. 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In all group, healing aspects were progressed from 7 days to 21 days in soft and bony tissue, but complete repair were not observed in bony defect 2. PDGF and control group were showed similar bony healing aspect , but bony healing in combination of PDGF-BB and Dex were observed slower aspect compared to PDGF and control group from early healing times. 3. There were no significant difference on activities of osteoclast and macrophages in bony healing between control and experimental group In conclusion, PDGF were not influenced on bony healing of defect and combination of PDGF-BB and Dex were showed slower healing through early healing times. it was considered that Dex compared to PDGF did influenced on early hone formation factors in healing period

• Journal of Periodontal and Implant Science
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• v.29 no.2
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• pp.355-373
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• 1999

Many researches have been reported that collagen as cellular stroma, matrix of grafting materials, mediator of agents for the purpose of promoting healing process invivo, but the responses in vivo were seen various. The goal of this experiment is to assess the effect of collagen on bony healing, through histological evaluation of implanted collagen on the calvarial defect in rats. 2-month-old Sprague-Dawley, 24 rats were used and 12 rats assigned to each group of control and test. Defect of 5mm in diameter was made on the calvarial bone with trephine bur. Following thorough saline rinse, defect of control group was left in empty and that of experimental group was filled with fibrillar collagen($COLLATAPE^{(R)}$, COLLA-TEC. INC. U.S.A.) soaked in saline. 3 rats in each group were sacrificed at 3, 7, 14, 21 days after operation respectively, and the tissue blocks were prepared for light microscope with H-E for evaluation of overall healing, with TRAP(tartrate resistant acid phosphatase) for evaluation of osteoclastic activity and with immunohistochemical staining for macrophages. The results were as follows : 1. In the control group, inflammatory responses were disappeared at day 14, but, in the experimental group inflammatory infiltrates were reduced at day 21. Thus, the experimental group showed more severe soft tissue inflammation than control group. 2. Both control and experimental group showed slight appositional growth at day 7 and gradual bony growth to 21th day. But, complete bony healing of the defect was not shown. There was no significant difference in bony healing between control and experimental group 3. Specific response of macrophages for implanted collagen was observed at day 14 in the experimental group. In conclusion, although fibrillar collagen caused inflammation of soft tissue during initial healing period, inflammatory responses by fibrillar collagen didn't inhibit bony regeneration and implanted collagen was biodegradaded by macrophages. Thus, we expect that fibrillar collagen can be used for useful mediator of graft materials or growth factors.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.135-146
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• 2001

Objective : Bone homeostasis is maintained by balance of bone formation and resorption. Therefore, bone related diseases arose by disturbance of this balance between osteoblast and osteoclast activities. To develop a successful screening system of the therapeutic components based on oriental medicine is essential to set out systematic approach for that purpose. Methods : This study was perforated Sprague-Dawley rat femur for bony defects(${\phi}5mm$) by the fissure bur. And experimetal group were treated with Cervi Pantotricuhum Cornu injection at both $Sh{\grave{e}}nsh{\tilde{u}}$(BL23) & $D{\grave{a}}zh{\grave{u}}(BL11)(0.2m{\ell})$. This was evaluated by radiography and histological analysis with in situ hybridization. Results : Cervi Pantotricuhum Cornu Herbal Acupuncture has weak effect on bony defect healing and this was evaluated by X-ray taking and histological analysis with in situ hybridization. Osteocalcin gene expression was not changed by Cervi Pantotricuhum Cornu Herbal Acupuncture in bony defects animal model. Conclusion : Taken together this study show that the Cervi Pantotricuhum Cornu herbal-acupuncture has a weak effect healing of bony defects, this type of approach might give a good chance to explore the favorable effects of Cervi Pantotricuhum Cornu herbal-acupuncture on bone tissue.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.173-183
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• 1998

$TGF-{\beta}$ is one of growth factors that may be involved in the formation of bone and cartilage. Multiple studies demonstrate that $TGF-{\beta}$ is involved in regulating cell proliferation, differentiation and matrix synthesis, events observed in frature healing. The apperance of $TGF-{\beta}$ in the fracture during healing was evaluated by immunohistologic localization of $TGF-{\beta}$ using antibody. Twenty Sprauge-Dawley strain white male rats, each weiging about 150grams were used and divided two groups. The one group, the $2{\times}2mm$ bony defect was formed in the right femur. The other group, $4{\times}2mm$ bony defect was formed in right femur. Both group were sacrificed at 3day, 1, 2, 3, 4 week and femur were harvested, paraffin sections were stained with H & E, MT stain, immunihistochemical staining with $TGF-{\beta}$ antibody and observed under light microscope. The result were as follows: 1. New bone formation and cartilagenous tissue was seen at 3day. And in the $2{\times}2mm$ bony defect group, $TGF-{\beta}$ stained the cell surounding new bone. 2. The osteoclast and trabecular was seen at 1week. $TGF-{\beta}$ stained the osteoblast and in the $2{\times}2mm$ bony defect group was stained more than $4{\times}2mm$ bony defect group. 3. The lamella bone and trabecule was seen from 3, 4week, and $TGF-{\beta}$ stained almost negative. From the above finding, we could concluded that $TGF-{\beta}$ stained the osteoblast at early stage and 1week, the peak stain was seen from 1week, and then decreased, almost negative stain was seen at 3, 4week.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.746-757
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• 1996

Bony defects may be found as a result of congenital anomalies, traumatic injury, automobile collisions and industrial accidents in the maxillofacial area. Such conditions are often associated with severs functional and esthetic problem. Various surgical procedure has been utilized in attempts to repair and reconstruct bony defects. Bone is a complex, living, constantly changing tissue. The architecture and composition of cancellous and cortical bone allow the skeleton to perform its essential mechanical functions. Periosteum covers the external surface of bone and consists of two layers : an outer fibrous layer and an inner more cellular and vascular layer. The inner osteogenic layer or cambium layer can form new bone while the outer layer firms part of the insertions of tendons, ligaments and muscles. This study was under taken to evaluate bone healing process on partial defect of calvarial bone with or without periosteum in rat. We made calvarial defects of different size(4mm, 6mm, 8mm) with periosteum or without periosteum in rat to study the effect of defect size on healing process. Control and experimental groups sacrified at 1, 2, 4, 6, 8 weeks, postoperatively. We examed the specimens by gloss findings, light microscophy, and fluorescent microscophy. The results were as follows. 1. Gloss findings: Control groups are larger bony defects than experimental groups after 2 weeks, and than control groups advanced healing of defected bone but experimental groups are lesser after 4, 6 weeks. After 8 weeks, bone defect has not been identified in control and experimental groups. 2. Light microscope: All defects of control groups are larger bony defects than experimental groups after 2 weeks. And than control groups show smaller defect after 4 weeks. After 8 weeks, the control group reveal pin-point sized, hardly identifiable defect space and the experimental group reveal small, but definite defect space. 3. Fluorescent microscope : Each week, new bone formation of control group is very similar to the experimental group. In this study, Osteogenesis of calvarial bone defects with periosteum or without periosteum was examined for 8 weeks in rats. The replaced periosteum had batter new bone formation than the removed periosteum.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.3
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• pp.361-378
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• 1992

The purpose of this investigation was to evaluate the effect of the porous hydroxyapatite particles (Interpore $200^{(R)}$) and guided tissue regeneration membrane ($Gore-Tex^{TM}$ augmentation material) on amount and shape of generating new bone adjacent to implant. Implants were placed immediately after extraction in the bilateral 3rd, 4th premolars of the mandible of the adult dogs. In all experimental groups, artificial bony defects were formed at the buccal cortex area, 3.3mm in width and 3.0mm in depth. In the control group : sutured without HA particles & membranes after placing implants, the experimental group 1 : membrane was place over the artificial bony defect, the experimental group 2 : bony defect was filled with HA particles and covered with membrane. The examination of bone-implant interfaces using light microscope and fluorescent microscope concluded as follows. 1. In all three experimental groups, osseointegration was observed without epithelial migration. 2. In the healing degree of bony defect area, the experimental group 1, 2 showed more prominent healing than control group, and the experimental group 1 showed the most excellent bone formation. 3. In fluorescent microscopic finding, bone remodeling was observed in regenerated bone tissue at defect area of experimental group 1, but in experimental group 2, irregular, discontinuous linear fluorescence was observed at the lower portion of defect area and sign of bone remodeling was weak.

• Journal of Periodontal and Implant Science
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• v.40 no.4
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• pp.180-187
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• 2010

Purpose: This study evaluated the spontaneous healing capacity of surgically produced cranial defects in rabbits with different healing periods in order to determine the critical size defect (CSD) of the rabbit cranium. Methods: Thirty-two New Zealand white rabbits were used in this study. Defects of three sizes (6, 8, and 11 mm) were created in each of 16 randomly selected rabbits, and 15-mm defects were created individually in another 16 rabbits. The defects were analyzed using radiography, histologic analysis, and histometric analysis after the animal was sacrificed at 2, 4, 8, or 12 weeks postoperatively. Four samples were analyzed for each size of defect and each healing period. Results: The radiographic findings indicated that defect filling gradually increased over time and that smaller defects were covered with a greater amount of radiopaque substance. Bony islands were observed at 8 weeks at the center of the defect in both histologic sections and radiographs. Histometrical values show that it was impossible to determine the precise CSD of the rabbit cranium. However, the innate healing capacity that originates from the defect margin was found to be constant regardless of the defect size. Conclusions: The results obtained for the spontaneous healing capacity of rabbit cranial defects over time and the underlying factors may provide useful guidelines for the development of a rabbit cranial model for in vivo investigations of new bone materials.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.1
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• pp.1-12
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• 1999

The purpose of this study was to evaluate the healing process of the calvarial defect filled with hydroxylapatite(HA) and $TGF-{\beta}$ in Rat. 72 Sprague-Dawly rats were divided into 3 groups, control and two experimental groups. Bony defect were artificially prepared in the calvaria of all 72 rats and followed by implantation of HA (experimental group of 24 rats) and HA+$TGF-{\beta}$(another experimental group of 24 rats) into the defects. Sequential sacrifice was performed at 1, 2, 4, 6, 8, 12 weeks of experiment. Obtained specimen was stained with Hematoxylin and Eosin, Masson's Trichrome and Immunohistochemistry. The results were as follows, 1. Granulation tissue was prominent on control group in 1 and 2 weeks. Bony defects were filled with dense fibrous tissue through the whole experimental period and osteoinduction could not be observed in all groups. 2. Inflammatory cell infiltration was prominent on control group in 1 and 2 weeks and osteoclastic activity was high in HA implanted experimental group at 1 and 2 weeks. 3. Inflammatory cell infiltration was less and maturation of fibrous tissue could be found on HA+$TGF-{\beta}$ implanted experimental group at 1 and 2 weeks. 4. Osteoconduction activity was high in HA+$TGF-{\beta}$ implanted experimental group at 2 and 4 weeks but there was no difference after 6 weeks among 3 groups. 5. In grafted site of HA+$TGF-{\beta}$ implanted group, osteonectin expression was slightly increased from 1 week to 6 weeks. In the host site, it was increased from 1 to 4weeks. 6. In grafted site of HA+$TGF-{\beta}$ implanted group, osteocalcin expression was high at 4 weeks. In the host site, we could find the difference among 3 groups. From above results, the HA with mixture of $TGF-{\beta}$ has the potentiality of promoting bone formation in the bony defect area in the rat.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.161-172
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• 2002

The present study evaluated the effects of guided tissue regeneration using xenograft material(deproteinated bovine bone powder), with and without biodegradable membrane in beagle dogs. Contralateral fenestration defects (6 ${\times}$ 4mm) were created 4 mm apical to the buccal alveolar crest of maxillary premolar teeth in 5 beagle dogs. Deproteinated bovine bone powders were implanted into fenestration defect and one randomly covered biodegradable membrane (experimental group). Biodegradable membrane was used to provide GTR. Tissue blocks including defects with soft tissues which were harvested following four & eight weeks healing interval, prepared for histo-phathologic analysis. The results of this study were as follows. 1. In control group, at 4 weeks after surgery, new bony trabecular contacted with interstitial tissue and osteocytes like cell were arranged in new bony trabecule. Bony lamellation was not observed. 2. In control gruop, at 8 weeks after surgery, scar-like interstitial tissue was filled defect and bony trabecule form lamellation. New bony trabecular was contacted with interstitial tissue but defect was not filled yet. 3. In experimental group, at 4 weeks after surgery, new bony trabecular partially recovered around damaged bone. But new bony trabecular was observed as irregularity and lower density. 4. In experimental group, at 8 weeks after surgery, lamella bone trabecular developed around bone cavity and damaged tissue was replaced with dense interstitial tissue. In conclusion, new bone formation regenerated more in experimental than control groups and there was seen observe more regular bony trabecular in experimental than control groups at 4 weeks after surgery. In control group, at 8 weeks after surgery, the defects was filled with scar-like interstitial tissue but, in experimental group, the defects was connected with new bone. Therefore xenograft material had osteoconduction but could not fill the defects. We thought that the effective regeneration of periodontal tissue, could be achieved using GTR with biodegradable membrane.

• Archives of Reconstructive Microsurgery
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• v.14 no.1
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• pp.42-49
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• 2005

Between June 1989 and may 2004 Ipsilateral vascularized fibular transposition was performed on nine patients with segmental tibial defects combined with infection following trauma. Ipsilateral vascularized fibular graft was performed on two or three stage according to the degree of infection. Initially free vascular pedicled graft was done followed by ipsilateral vascularized fibular graft. Type of free flap used is scapular free flap 3 cases, latissimus dorsi free flap 5 cases and dorsalis pedis flap 1 cases. The patients were followed for an average of 3.4 years. the average time to union was 6.7 months, and in all patients the graft healed in spite of complication. Complication was free flap venous thrombosis in 1 cases, persistent infection in 1 cases, delayed bony union at the distal end of fibular graft in 2 cases. The results showed that more faster bony union was seen in which cases firmly internally fixated and more faster hypertrophy of graft in which cases was permitted to ambulate on early weight bearing and more faster healing in which cases debrided more meticulously. Reconstruction of tibia defect with free flap followed by Ipsilateral fibular transposition is a useful and safe method to avoid the potential risk of infection for patients with tibial large bone defect and soft tissue defect associated with infection.