• The Journal of Korean Physical Therapy
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• v.14 no.4
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• pp.412-422
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• 2002

The use of biochemical markers of bone turnover may be particular interest in the investigation of bone disorders with osteoporosis. Serum osteocalcin(OC), total alkaline phosphatase and procollagen C, reflecting bone formation, and urinary pyridinium cross-links excretion, reflecting bone reabsorption have been measured in hyperthyroidism, postmenopause women, after testosterone supplementation, androgen, testosterone and estrogen deficiency, bone mineral density degree, age duration. Bone marks which is reflect to metabolic bone disorders are biochemical indices method to measure enzyme activity about bone formation, bone absorption and bone components in blood or urine. Bone metabolism biochemical marks are correlated with osteophorotic agents and also represent significantly different between bone mineral density and bone biochemical marks. Therefore if we develope and use bone metabolism marks which have higher sensitivity and specificity in bone formation and bone absorption, I think that these bone biochemical marks can have utility in the clinical application to predict osteoporosis risk group, bone loss, bone fracture and response degree to treatment of osteoporosis risk groups.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.45.1-45.7
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• 2016

Background: We evaluated and compared the outcomes of different ossification processes in patients with alveolar cleft in whom correction was performed using endochondral bone graft or intramembranous bone graft. Methods: The patients were divided into two groups: the endochondral bone (iliac bone or rib bone) graft group and the intramembranous bone (mandibular bone) graft group. Medical records and radiologic images of patients who underwent alveolar bone grafting due to alveolar cleft were analyzed retrospectively. Through postoperative and follow-up radiologic images, the height of the interdental bone septum was classified into four types based on the highest point of alveolar ridge. Then, the height of the interdental bone septum and the area of the bone graft were evaluated according to the type of bone graft. In addition, the occurrence of complications and the need for an additional bone graft, the result of postoperative orthodontic treatment, and the eruption of impacted teeth were investigated. Results: Thirty patients were included in this study. There was no significant difference in the change of the interdental bone height and the area of the bone graft according to the type of bone. There was no significant difference in the success rate of the surgery according to the type of bone. One patient underwent an additional bone graft surgery during the follow-up period. Conclusions: The outcomes of alveolar bone grafting were not significantly different according to the type of bone graft. If appropriate to the size of the recipient site, the chin bone is a useful graft material in alveolar cleft, as is the iliac bone.

• Journal of Periodontal and Implant Science
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• v.46 no.3
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• pp.152-165
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• 2016

Purpose: This study investigated the effects of bone density and crestal cortical bone thickness at the implant-placement site on micromotion (relative displacement between the implant and bone) and the peri-implant bone strain distribution under immediate-loading conditions. Methods: A three-dimensional finite element model of the posterior mandible with an implant was constructed. Various bone parameters were simulated, including low or high cancellous bone density, low or high crestal cortical bone density, and crestal cortical bone thicknesses ranging from 0.5 to 2.5 mm. Delayed- and immediate-loading conditions were simulated. A buccolingual oblique load of 200 N was applied to the top of the abutment. Results: The maximum extent of micromotion was approximately $100{\mu}m$ in the low-density cancellous bone models, whereas it was under $30{\mu}m$ in the high-density cancellous bone models. Crestal cortical bone thickness significantly affected the maximum micromotion in the low-density cancellous bone models. The minimum principal strain in the peri-implant cortical bone was affected by the density of the crestal cortical bone and cancellous bone to the same degree for both delayed and immediate loading. In the low-density cancellous bone models under immediate loading, the minimum principal strain in the peri-implant cortical bone decreased with an increase in crestal cortical bone thickness. Conclusions: Cancellous bone density may be a critical factor for avoiding excessive micromotion in immediately loaded implants. Crestal cortical bone thickness significantly affected the maximum extent of micromotion and peri-implant bone strain in simulations of low-density cancellous bone under immediate loading.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.3
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• pp.253-263
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• 1995

Microsurgical vascularized bone transfer has the disadvantages of limitation of available donor sites, loss of donor function, and the possibility of donor site defects or deformity. To overcome these shortage of current microsurgical tissue transfer, the method of creating the neovascularized free flap has been introduced. Potentially, this technique must be an innovation in providing the free vascularized bone grafts that are not limited by natural vascular anatomy. But, as could be imagined technique resulted in unavoidable donor bone defect and additional operation for harvesting the autologous bone. The purpose of this study was to evaluate the efficacy of demineralized allogeneic bone as a possible substitute for autologous bone in fabricating the neo-osseous flap. By histologic, microangiographic and radioisotope method, the viability and vascularity of neo-osseous flap, which has been fabricated using allogeneic bone or autologous bone, was assessed in rat model. After 6 weeks, demineralized allogeneic bone showed consistent bone formation and neovascularization. The clinical and microscopic findings of demineralized allogeneic bone group were inferior to those of autogenous bone with regard to bone regeneration. The amount of bone blood floow per dry weight of demineralized allogeneic bone group was significantly higher than that of autogenous bone, even higher that of control intact iliac bone. In conclusion, findings supported that allogeneic bone could be the potential substitute for autologous bone source in creating a prefabricated neo-osseous flap.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.137-141
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• 2002

Taurine, amino acid, chemically known as 2-amino ethane sulphonic acid was discovered more than two hundred years ago from ox bile. it is widely distributed in both mammals and nonmammals. It is found in considerably high amount in hUl11an: a normal adult of 70 kgs contains about 70 grams of taurine. Taurine with this much concentration, is involved in almost all life processes. Its deficiency causes several abnormalities in major organs like brain, eye and heart. Taurine-bone interaction is latest addition to its long list of actions. In bone cells, taurine is also found in high concentration. Taurine is found to help in enhancing the bone tissue formation which is evidenced by increased matrix formation and collagen synthesis. Besides stimulating the bone tissue formation, it also inhibits the bone loss through inhibiting the bone resorption and osteoclast formation. Thus, taurine acts as a double agent. In addition to these two major actions of taurine in bone, it also has beneficial effect in wound healing mld bone repair. Taurine possess radioprotective properties, too. As it is a naturally available molecule, it can be used as a preventive agent. Taurine has a potential to replace bisphosphonates which are currently in use for the inhibition of bone loss but this needs in depth study. As taurine is involved in bone formation and inhibition of bone loss, a detailed study can make it a single marker of bone metabolism. All these taurine-bone interaction is a symbol of their deep involvement but still require further extension to make taurine as a choice for tile sound bone health.

• The Journal of the Korean dental association
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• v.48 no.4
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• pp.275-279
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• 2010

Dental implant restoration in partial or full edentulous state has become the standard treatment in recent years. Bone graft with guided bone regeneration technique has been regarded as one of the most reliable methods to restore the bone defect area due to periodontal disease or dental trauma. Bone graft materials and membrane are the essential component of guided bone regeneration; however, a variety of bone graft materials confuse us in implant dentistry. Autogenous bone is the recognized standards in implant dentistry owing to its osteogenesis potential. Despite of its disadvantages, grafting autogenous bone is the most reliable methods. Even though the development of new bone grafts materials, autogenous bone is useful in exposed implant thread and total lack of buccal or lingual bone. Allogenic, xenogenic and synthetic bone have the osteoconductive and osteoinductive potential. These materials could be used successfully in self-contained cavity such as sinus cavity and three-wall defects. In this article, application of bone graft material is suggested according to the function of bone graft materials.

• Biomaterials and Biomechanics in Bioengineering
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• v.4 no.1
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• pp.33-44
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• 2019

This paper presents a novel structural composition for artificial bone scaffolds with an appropriate biocompatibility and biodegradability capability. To achieve this aim, carbon nanotubes, due to their prominent mechanical properties, high biocompatibility with the body and its structural similarities with the natural bone structure are selected in component of the artificial bone structure. Also, according to the piezoelectric properties of natural bone tissue, the barium titanate, which is one of the biocompatible material with body and has piezoelectric property, is used to create self-healing ability. Furthermore, due to the fact that, most of the bone tissue is consists of hydroxyapatite, this material is also added to the artificial bone structure. Finally, polycaprolactone is used in synthetic bone composition as a proper substrate for bone growth and repair. To demonstrate, performance of the presented composition, the mechanical behaviour of the bone scaffold is simulated using ANSYS Workbench software and three dimensional finite element modelling. The obtained results are compared with mechanical behaviour of the natural bone and the previous bone scaffold compositions. The results indicated that, the modulus of elasticity, strength and toughness of the proposed composition of bone scaffold is very close to the natural bone behaviour with respect to the previous bone scaffold compositions and this composition can be employed as an appropriate replacement for bone implants.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.483-485
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• 1998

6Bone(IPv6 Backbone)은 IPv6 환경의 개발 촉진 및 진화를 위해 만든 전세계적인 실험망이다. 본 논문은 국내 6Bone인 6Bone KR의 구축을 위해 주소 할당 및 라우팅 규칙을 정의한 내용을 기술한다. 기존의 6Bone 주소 구조를 알아보고, 6Bone KR의 주소 체계가 어떻게 기존의 6Bon을 따르면서, 6Bone KR의 계층적 전개를 위한 연결 규칙을 가지는 가를 살펴본다. 그리고 현재 6Bone KR이 구성된 상황과 개발한 연결 테스트의 프로그램을 소개한다. 이밖에 6Bone KR진화를 위한 몇 가지 고려사항들을 분석하고, 이것을 기반으로 Renumbering을 이용한 새로운 이동 IPv6 환경을 제안한다.

• Journal of Biomedical Engineering Research
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• v.33 no.4
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• pp.213-222
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• 2012

While much has been learned about the mechanisms of metastatic spread of cancer to bone, there has been little headway in establishing guidelines for monitoring the alteration in bone quality and estimating fracture risk. The aims of this study are, therefore, 1) to evaluate bone quality induced by metastatic bone tumor by analyzing the characteristics on bone microarchitecture and degree of bone mineralization and 2) analyze fracture risk increased secondary to the bone quality changes by metastatic bone tumor through calculating mechanical rigidities based on in-vivo micro CT images. For this study, eighteen female SD rats (12 weeks old, approximate 250 g) were randomly allocated in Sham and Tumor groups. W256 (Walker carcinosarcoma 256 malignant breast cancer cell) was inoculated in the right femur (intraosseous injection) in Tumor group, while 0.9% NaCl (saline solution) was injected in Sham group. The right hind limbs of all rats were scanned by in-vivo micro-CT to acquire structural parameters and degree of bone mineralization at 0 week, 4 weeks, 8 weeks, and 12 weeks after surgery. At the same time, urine was collected by metabolic cages for a biochemical marker test in order to evaluate bone resorption. Then, bone metastasis had been directly identified by positron emission tomography. Finally, axial, bending and torsional rigidities had been calculated based on in-vivo micro CT images for predict fracture risk. The results of this study showed that metastatic bone tumor might induce significant decrease in bone quality and increase of fracture risk. This study may be helpful to monitoring a degree of bone metastasis and predicting fracture risk due to metastatic bone tumor. In addition, this noninvasive diagnostic methodology may be utilized for evaluating other bone metabolic diseases such as osteoporosis.

• Journal of Periodontal and Implant Science
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• v.40 no.5
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• pp.220-226
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• 2010

Purpose: This study was performed to evaluate the periodontal wound healing effect of particulate equine bone mineral on canine alveolar bone defects. Methods: Twelve adult male beagle dogs were used as study subjects. The mandibular second and fourth premolars were extracted prior to the experimental surgery, and the extraction sites were allowed to heal for 8 weeks. After periodontal probing, two-walled defects were created at the mesial and distal sides of the mandibular third premolars bilaterally, and the defects were filled with equine particulate bone with collagen membrane or bovine particulate bone with collagen membrane, or collagen membrane alone. The defects without any treatment served as negative controls. After probing depth measurement, animals were sacrificed at 10, 16, and 24 post-surgery weeks for micro-computed tomographic and histomorphometric analysis. Results: The equine particulate bone-inserted group showed significantly decreased values of probing depth and first bone contact compared to the negative control and collagen membrane alone groups at weeks 10, 16, and 24 (P<0.05). There were no significant differences in the new cementum length, newly-formed bone area, or newly-formed bone volume between equine particulate bone- and bovine particulate bone-inserted groups, both of which showed significantly increased values compared to the negative control and collagen membrane alone groups (P<0.05). Conclusions: Equine particulate bone showed significant differences in probing depth, first bone contact, new cementum length, newly formed bone area, and bone volume fraction values when compared to the negative control and collagen membrane alone groups. There were no significant differences between equine and bovine particulate bone substitutes in these parameters; therefore, we can conclude that equine particulate bone is equivalent to bovine bone for periodontal regeneration.