• The Journal of the Korean bone and joint tumor society
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• v.13 no.2
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• pp.180-184
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• 2007

The etiology of post-traumatic, and presumably post-fracture, osteolysis of the pubic bone is unknown, although the pathological process is similar to bony destruction related to bone tumor or osteomyelitis. We have seen and wish to report one patient in whom destruction of the pubic bone was a prominent feature of the healing process following trauma.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.46.1-46.1
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• 2009

우리 몸의 뼈를 재료적인 측면으로 보면, 주로 나노 크기의 콜라겐과 아파타이트로 이루어 져 있는 복합체이다. 때문에 최근 생체 모사적인 측면에서 나노 크기의 생체 활성 재료를 이용하여 골 재생 촉진이 우수한 지지체를 제작하고자 하는 많은 연구 들이 진행되고 있다. 이러한 나노 크기의 재료는 일반적인 마이크로 크기의 생체 재료에 비해 표면적이 월등히 크기 때문에 생체 활성 (bioactivity)이 우수하다고 알려져 있으며, 이를 골 재생용 지지체의 구성 재료로 사용하였을 경우 기계적 강도 또한 향상 시킬 수 있다고 알려져 있다. 따라서 본 연구에서는 나노 크기의 HA, CaSiO3 등 다양한 나노 생체 활성 입자들을 침전법 (precipitation method)을 통하여 제조하였으며, 이를 이용하여 골 재생 촉진을 위한 3차원 지지체를 제조 하였다. 또한 기존의 마이크로 크기의 생체 재료로 제작된 지지체와의 생물학적, 기계학적 비교 평가를 통하여 나노크기의 재료의 우수성을 입증하고자 하였다. 결론적으로, 나노 크기의 재료로 제작된 골 재생용 지지체의 경우 기존의 마이크로 크기의 재료로 제작된 지지체보다 골세포의 부착, 증식 및 분화능이 우수하였고, 지지체의 기계적 강도 또한 향상됨을 알 수 있었다. 이를 통하여 나노 크기의 생체 활성재료는 골 재생 촉진을 위한 지지체 제작에 응용 가능성이 높음을 확인 할 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1769-1775
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• 2010

Menopause is often associated with the incidence of several chronic diseases including osteoporosis, cardiovascular disease, and obesity. The purpose of this study was designed to evaluate the possibility of osteoporosis prevention in postmenopausal women. In this study, we investigated the effects of Ecklonia stolonifera (ES) extracts on bone turnover markers in ovariectomized rats. For this study, the following four groups of 9-week-old Sprague-Dawley rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with ES extracts. We measured the osteocalcin and C-telopeptide of collagen cross-links (CTx) content, enzyme ALP activity in serum and collagen content in the cartilage, bone, skin and lungs. We found that the levels of indicators of bone metabolism such as alkaline phosphatase (ALP), osteocalcin and CTx were lower in rats in the ES extract group than the OVX-CON group. In addition, the collagen contents in the bone, cartilage, skin and lungs decreased in response to ovariectomy, but the levels of collagen were greater in the bone of rats that were treated with ES extract than in the bone of rats in the OVX-CON group. These results suggest that the ES may be an effective functional food to prevent osteoporosis in postmenopausal women.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.20.1-20.1
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• 2011

타이타늄의 내부식 특성은 분해하기 어려운 산화물의 보호피막을 형성 함으로서 무독성의 생체친화적 성질을 가지고 있어 심장밸브, 인공 뼈 등 신체 조직의 이식에 사용될 만큼 인체에 무해한 금속으로 의료용으로 많이 응용되고 있다. 본 강연에서는 생체재료로써 의료용 타이타늄의 적용현황을 소개하고, 이를 통해 타이타늄의 가치를 다시 한번 재고하고자 한다. 타이타늄 임플란트에서 그 표면과 골사이의 골유착(osseointegration)은 성공적인 임상결과를 얻기 위한 중요한 요소 중의 하나이다. 1960년대에는 기계가공 된 매끈한 형태의 타이타늄 표면을 시작으로 골유착을 얻고자 하였다. 이러한 시도를 통해 임플란트가 점차 대중화 되면서 1980년대 부터 타이타늄 표면과 골과의 유착을 조기에 실현하고, 골유착 강도를 강화하기 위해 다양한 표면기술이 개발 되기 시작하였다. 크게는 1. 표면적 증대 기술, 2. 화학적 방식을 통한 표면기술, 3. 생체활성 유도형 표면기술, 4. 서방출 등을 응용한 골유도 및 활성 조절형 표면기술 등이 개발되어 제품화 되거나 그 연구가 진행 중에 있다. 다양한 표면기술에 대한 흐름을 이해하고 이에 대한 장, 단점을 이해함으로써 앞으로 기술적으로 극복해 나가야 할 과제를 제시하고자 한다. 또한 다양한 표면기술에 대한 유효성과 그에 대한 중, 장기 안전성에 대한 중요성을 이해하고 이를 평가하기 위한 여러 가지 절차와 방법 소개를 통해 신뢰성 있는 연구개발이 될 수 있기 바란다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.10
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• pp.887-895
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• 2013

Metastatic bone cancer, the cancer which occurred in the various organs and progressively spread to bone, is one of the complications in cancer patients. This cancer is divided into the osteoblast and osteolytic metastasis. Although Computer Tomography(CT) could be an useful tool in diagnosis of bone metastasis, lesions are often missed by the visual inspection and it makes clinicians difficult to detect metastasis earlier. Therefore, in this study, we construct a three-dimensional(3D) volume rendering data from tomography images of the chest CT, and apply a 3D based image processing algorithm to them for detection bone metastasis lesions. Then we perform a three-dimensional visualization of the detected lesions.From our test using 10 clinical cases, we confirmed 94.1% of average sensitivity for osteoblast, and 90.0% of average sensitivity, respectively. Consequently, our findings showed a promising possibility and potential usefulness in diagnosis of metastastic bone cancer.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.2
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• pp.58-62
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• 2002

The incidence of giant cell tumors represents only 5% to 10% of all bone tumors. Occurrence on the small bones of the hand and foot are very rare. They typically present with pain and sometimes a pathologic fracture or even soft tissue extension. The radiographic appearance is highly characteristic. An eccentric osteolytic lesion is seen, producing cortical thinning and expansion, and possessing a delicate trabecular pattern. In tarsal bones, poorly or well-defined osteolytic lesions of variable size are encountered. Surgical treatment remains the preferred therapy. Marginal or wide en bloc resection has had far better results in term of local recurrence. Several authors have suggested extended curettage and cement as an alternative to en bloc resection. Follow-up is necessary to monitor for both local recurrence and the infrequent pulmonary metastases.

• The korean journal of orthodontics
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• v.40 no.3
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• pp.167-175
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• 2010

Objective: The aim of this study was to validate the Periotest values for the prediction of orthodontic mini-implants' stability. Methods: Sixty orthodontic mini-implants (7.0 mm $\times$ $\emptyset1.45$ mm; ACR, Biomaterials Korea, Seoul, Korea) were inserted into the buccal alveolar bone of 5 twelve month-old beagle dogs. Insertion torque (IT) and Periotest values (PTV) were measured at the installation procedure, and removal torque (RT) and PTV were recorded after 12 weeks of orthodontic loading. To correlate PTV with variables, the cortical bone thickness (mm) and bone mineral density (BMD) within the cortical bone and total bone area were calculated with the help of CT scanning. Results: The BMD and cortical bone thickness in mandibular alveolus were significantly higher than those of the maxilla (p < 0.05). The PTV values ranged from -3.2 to 4.8 for 12 weeks of loading showing clinically stable mini-implants. PTV at insertion was significantly correlated with IT (-0.51), bone density (-0.48), cortical bone thickness (-0.42) (p < 0.05) in the mandible, but showed no correlation in the maxilla. PTV before removal was significantly correlated with RT (-0.66) (p < 0.01) in the mandible. Conclusions: These results show that the periotest is a useful method for the evaluation of mini-implant stability, but it can only be applied to limited areas with thick cortical and high density bone such as the mandible.

• Journal of Life Science
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• v.19 no.12
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• pp.1841-1846
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• 2009

Menopause is often associated with the incidence of several chronic diseases including osteoporosis, cardiovascular disease, and obesity. Hormone replacement therapy (HRT) is an effective regimen that has been found to prevent these diseases in postmenopausal women. However, HRT is accompanied by an increased risk of unfavorable outcomes. Therefore, this study was conducted to evaluate the effects of Ecklonia cava, a kind of seaweed, extract on bone turnover markers in symptomatic menopausal women. For this study, the following four groups of 9-week-old Sprague-Dawley rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with Ecklonia cava extracts. The optimum extraction temperature and solvent of Ecklonia cava were found to be $80^{\circ}C$ and 80% ethanol. We measured the osteocalcin and CTx content, enzyme ALP activity in serum and collagen content in the cartilage, bone, skin and lungs. We found that the levels of indicators of bone metabolism such as ALP, osteocalcin and CTx were lower in rats in the Ecklonia cava extract group than the OVX-CON group. In addition, the collagen contents in the bone, cartilage, skin and lungs decreased in response to ovariectomy, but the levels of collagen were greater in the bone of rats that were treated with Ecklonia cava extract than in the bone of rats in the OVX-CON group. According to these results, we were able to know the effects of Ecklonia cava extract on bone aging in ovariectomized rats. Consequently, we expect Ecklonia cava extract to have an effect on bone aging in postmenopausal women.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2005.03a
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• pp.83-83
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• 2005

• The korean journal of orthodontics
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• v.38 no.4
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• pp.228-239
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• 2008

Objective: The aim of this study was to evaluate the strain induced in the cortical bone surrounding an orthodontic microimplant during insertion. Methods: A 3D finite element method was used to model the insertion of a microimplant (AbsoAnchor SH1312-7, Dentos Co., Daegu, Korea) Into 1 mm thick cortical bone with a pre-drilled hole of 0.9 mm in diameter. A total of 1,800 analysis steps was used to simulate the 10 turns and 5 mm advancement of the microimplant. A series of remesh in the cortical bone was allowed to accommodate the change in the geometry accompanied by the implant insertion. Results: Bone strains of well higher than 4,000 microstrain, the reported upper limit for normal bone remodeling, was observed in the bone along the whole length of the microimplant. At the bone in the vicinity of the screw tip, strains of higher than 100% was recorded. The insertion torque was calculated at approximately 1.2 Ncm which was slightly lower than those measured from the animal experiment using rabbit tibias. Conclusions: The insertion process of a microimplant was successfully simulated using the 3D finite element method which showed that bone strains from a microimplant insertion might have a negative impact on physiological remodeling of bone.