• The Journal of the Korean dental association
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• v.51 no.3
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• pp.138-147
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• 2013

Orthodontic tooth movement is a unique process which tooth, solid material is moving into hard tissue, bone. Orthodontic force in general provides the strain to the PDL and alveolar bone, which in turn generates the interstitial fluid flow(in detail, fluid flow in PDL and canaliculi). As a results of matrix strain, periodontal ligament cells and bone cells are deformed, releasing variety of cytokines, chemokines, and growth factors. These molecules lead to the orthodontic tooth movement(OTM). In these inflammation and tissue remodeling sites, all of the cells could closely communicate with one another, flowing the information for tissue remodeling. To accelerate the rate of OTM in future, local injection of single growth factor(GF) or a combination of multiple GFs in the periodontal tissues might intervene to stimulate the rate of OTM. Corticotomy is effective and safe to accelerate OTM.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.365-370
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• 2011

Structure-bone noise is an important aspect to consider during the design and development of a vehicle. Reduction of structure-bone noise of the compartment in a vehicle is an important task in automotive engineering. Many methods which analyze transfer path of noise have been used for structure-bone noise. The existing method to measure of frequency response function of transfer path has been tested by removing a source. This Paper presents an experimental analysis about Transfer Path Analysis of the vehicle interior noise according to Excitation or not. To identify these points of difference, experiment were conducted through an experimental test using simulation vehicle.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.9 no.1
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• pp.32-36
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• 1979

The author studied on the side effects of x-ray irradiation to the developing mandible of the gestation and period of grow the stage rats. For experimental observation, 100 rads, 200 rads, and 300 rads of x-ray were irradiated in regular order at the lower abdomen of the 8th day gestated rats. 5 weeks after conception, their offspring were sacrificed and their mandibles were extracted with intact form. All the extracted mandible were examined for their developing modes histological findings. The results were as followed 1) In 100-200 rads irradiated rats offsprings, their mandidles were not revealed any morphological changes except of the irregular pattern of trabeculatum. In accompany with this findings, most of all the fibroblasts and osteoclasts had their nucleus with shrunken and eccetric position. 2) In according to the increasing x-ray irradiation, marked advent of osteoclast and cortical bone resorption were observed. 3) In 300 rads irradiated rats offsprings, there irregular pattern of trabeculae and windening of bone morrow cavity in their alveolar proper.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.3
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• pp.197-206
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• 2021

Carnosol is a phenolic diterpene phytochemical found in rosemary and sage with reported anti-microbial, anti-oxidant, anti-inflammatory, and anti-carcinogenic activities. This study aimed to investigate the effect of carnosol on the lineage commitment of mouse bone marrow-derived mesenchymal stem cells (mBMSCs) into osteoblasts and adipocytes. Interestingly, carnosol stimulated the early commitment of mBMSCs into osteoblasts in dose-dependent manner as demonstrated by increased levels of alkaline phosphatase activity and Alizarin red staining for matrix mineralization. On the other hand, carnosol significantly suppressed adipogenesis of mBMSCs and downregulated both early and late markers of adipogenesis. Carnosol showed to induce osteogenesis in a mechanism mediated by activating BMP signaling pathway and subsequently upregulating the expression of BMPs downstream osteogenic target genes. In this context, treatment of mBMSCs with LDN-193189, BMPR1 selective inhibitor showed to abolish the stimulatory effect of carnosol on BMP2-induced osteogenesis. In conclusion, our data identified carnosol as a novel osteoanabolic phytochemical that can promote the differentiation of mBMSCs into osteoblasts versus adipocytes by activating BMP-signaling.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.719-732
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• 2007

Purpose: Various bone graft materials are being used for periodontal tissue regeneration. Th materials are being developed continuously for ideal clinical effects. Therefore, it is necessary to identify the clinical characteristics of each bone graft material through comparing the various bone graft materials statistically and in doing so, proposing a more efficient bone graft material. In this study, the following results were attained through comparing the clinical effects among the bone graft materials, using the statistical method based on the clinical studies published at the department of periodontology of Yonsei hospital. Materials and Method: 6 selected studies of department of Periodontology at Yonsei University Hospital were based on clinical study of bone grafting in intrabony defects. It was compared the clinical parameters among the 6 clinical studies, using the statistical META analysis. Result: When comparing the probing depth reduction, there was a relatively great amount of decease when using the xenograft, Anorganic Bovine Derived Hydroxapatite Bone Matrix/Cell Binding Peptide(ABM/P-15: PepGen $P-15^{(R)}$) and the autogenous bone and absorbable membrane, d, 1-alctide/glycolide copolymer(GC: $Biomesh^{(R)}$). The allogfrafts showed a relatively low decrease in the probing depth and clinical attachment change. It also showed a slight decrease in the bone probing depth. The allografts showed various results according to different bone graft materials. When comparing the ABM/P-15 and bovine bone $powder(BBP^{(R)})$, ABM/P-15 showed a relatively high clinical attachment level and the bovine bone powder showed a relatively high clinical attachment level. The probing depth change and gingival recession change showed a lower value than the mean value between the two bone graft materials. The synthetic bone showed a relatively high decrease in clinical attachment level and periodontal probing depth change. There was a relatively larger amount of gingival recession when using Bioactive Glass(BG) but a relatively low bone regeneration effect was seen. Conclusion: Good restorative results of the periodontal tissue can be attained by applying the various bone graft materials being used today after identifying the accurate clinical effects.

• Journal of Acupuncture Research
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• v.24 no.5
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• pp.13-22
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• 2007

Objectives : The differentiation of osteoblasts is controlled by various growth factors and matrix protein expressed in bone. The aim of this study was to investigate the effects of many herbs medicine(KHBJs) for bone healing that induces osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic effects of KHBJs were evaluated by using cell proliferation(WST-8) assay, alkaline phosphatase(ALP) activity assay, colorimetric analysis of vascular endothelial growth factor(VEGF) expression in human osteoblast like SaOS-2 cell. Also, osteogenic activity of KHBJ fractions(KHBJB and KHBJR) by activity guided fractionation were evaluated. Results : About 7 KHBJs had effect on the proliferation of osteoblast like SaOS-2 cells, and dose-dependently increased alkaline phosphatase(ALP) activity. KHBJs markedly increased expression for VEGF. Fractionated KHBJs(KHBJB or KHBJR) not enhanced more than KHBJs on osteogenic activity in SaOS-2 cells. Conclusions: This study found that 7 KHBJs had effect on proliferation, ALP activity, and VEGF expression in osteoblast like SaOS-2 cells. These results propose that KHBJs can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.

• Journal of Korean Dental Science
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• v.5 no.1
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• pp.21-28
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• 2012

Purpose: In this study the bone healing ability of autogenous tooth bone graft material as a substitute material was evaluated in a mini-pig cranial defect model through histologic examinations and osteonectin reverse transcription polymerase chain reaction (RT-PCR) quantitative analysis. Materials and Methods: A defect was generated in the cranium of mini-pigs and those without a defect were used as controls. In the experimental group, teeth extracted from the mini-pig were manufactured into autogenous tooth bone graft material and grafted to the defect. The mini-pigs were sacrificed at 4, 8, and 12 weeks to histologically evaluate bone healing ability and observe the osteonectin gene expression pattern with RT-PCR. Result: At 4 weeks, the inside of the bur hole showed fibrosis and there was no sign of bone formation in the control group. On the other hand, bone formation surrounding the tooth powder granule was observed at 4 weeks in the experimental group where the bur hole was filled with tooth powder. Osteonectin gene expression; there was nearly no osteonectin expression in the control group while active osteonectin expression was observed from 4 to 12 weeks in the experimental group. Conclusion: We believe this material will show better results when applied in a clinical setting.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.1-28
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• 1990

The severe atrophic edentulism with poor neuromuscular control militates against successful conventional denture therapy. To such situation, a prescribing of dental implant treatment has been considered with some probability. Implant materials used as a trial for dental implants includes metals, plastic polymers and ceramics. The purpose of this study was to observe histologic response in osseointegration process at titanium implant-tissue interface based on biocompatibility at specific period of sequential natures which were divided into a half month, one, month, two months, three months and immediate as a base line. In this study, unilateral lower left premolar and molar teeth were extraced in three dogs. After allowing to heal for 6 months, three kinds of osseointegrated implant, $Br{\aa}nemark$, Corevent and kimplant(a prototype of SNU implant study)were inserted in each dog respectively according to the above sequence from front to back. The specimens were taken from those dogs at the same time since implant were inserted quite reverse order of the specified periods, and decalcified and processed for histologic examination for the light microscopy and the electron microscopy. The microscopic histologic findings at the interface between titanium implants and tissue were interpretated as follows : A. Light microscopic findings : a. Immediate : Implant were surrounded by compact bone and spongy bone. Microcrak was observed in the superficial bone tissue. Osteocytes were disappeared and bone lacunae were observed as a vacant space in some parts. In the contacting with the spongy bone, bone trabeculae and bone marrow were in contact with the implant. b. A half Month : Osteoblasts exist as a monolayer in th inner bone trabeculae and do bone additiocn. Osteoblasts&inflammatory cells were observed in some parts. c. One Month : The presence of osteoclasts decreased. Osteoblasts did active bone fromation, and bone marrow was in contact with the implant in the many places. d. Two Months : Bone formation was advanced in comparison with the b and c. The presence of osteoclsts was not observed. e. Three Months : The superficial bone tissue contacted with the implants was entirely composed by the compact bone. B. Electron microscopic findings : a. A half month and one month group : In the parts of the active bone formation, osteoblasts with the well developed endoplasmic reticulum and Golgi apparatus were arranged in the monolayer. In the parts of the bone resorption, ruffled border was well developed and many osteoclasts with the well-developed golgi apparatus, mitochondria, vacuole, vesicle and lysosome were existed. b. Three months group : No osteoblasts were observed in the superficial bone tissue. Bone matrix with collaen fiber was observed. c. No significant dirrerence in the histologic findings was observed in $Br{\aa}nemark$, Core-vent and kimplant.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.3
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• pp.265-273
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• 2000

Purpose : The aim of this study was to evaluate the bone mineral density of iliac and tibial bone which are frequently selected as autogenic bone graft donor sites, and to evaluate the efficiency of this method as a guideline for the selection of bone graft donor site. Materials and Methods : In this study 61 male and 70 female volunteers at Chungbuk National University Hospital were involved between Jan. 1998 to Sept. 1999. We measured bone mineral density of the iliac and the tibial bone using dual energy X-ray absorptiometry. We evaluated the data using the SAS system for Windows and bone mineral density of the lumbar was used for control. Results : Age showed the highest correlation in correlation matrix between physical and bone variables. Height and weight showed lower correlation of linear increment. In man, the change of bone density according to age demonstrated linear decrease irrespective of the lumbar, ilium, and tibia. In woman, the change of bone density according to age showed cubic form, which increased in the third and forth decade. So it had a peak bone mass on about 35 year-old, thereafter, the change of bone density slowly decreased until 50 year-old, but it rapidly decreased after 50 year-old and it slowly decreased again after 65 year-old. Both in all subjects and subject with osteoporosis, the change of bone mineral density according to age showed statistically significant decrease in lumbar and tibia, but ilium was irrespective. Conclusion : In patients of aged or with osteoporosis, ilium demonstrated less tendency of decrease in bone mineral density than tibia. So this preliminary study suggested that ilium seemed better donor site for autogenic bone graft than tibia.