• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권6호
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• pp.557-564
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• 2000

The bone graft materials can be grossly divided into autogenous bone, allogenic bone, xenogenic bone, and alloplastic material. Much care was given to other bone graft materials away from autogenous bone due to its additional operation for harvesting, delayed resorption and limitation of quantity. Demineralized freeze-dried bone(DFDB) and hydroxyapatite are the representatives of bone graft materials. As resorbable hydroxyapatite is developed in these days, the disadvantage of nonresorbability can be overcome. So we planned to study on the strength and the bone formation at the rats calvarial defects of DFDB graft and those of the composite graft with DFDB and resorbable hydroxyapatite. We used the 16 male rats weighting range from 250 to 300 gram bred under the same environment during same period. After we made the 6mm diameter calvarial defect, we filled the DFDB in 8 rats and DFDB and resorbable hydroxyapatite in another 8 rats. We sacrificed them at the postoperative 1 month and 2 months with the periostium observed. As soon as the specimens were delivered, we measured the compressive forces to break the normal calvarial area and the newly formed bone in calvarial defect area using Instron(Model Autograph $S-2000^{(R)}$, Shimadzu, Japan). The rest of the specimens were stained with H&E(Hematoxylin & Eosin) and evaluated with the light microscope. So we got the following results. 1. In every rats, there was no significant difference between the measured forces of normal bone area and those of the bone graft area. 2. In 1 month, the measured forces at DFDB graft group were higher than those of the DFDB and resorbable hydroxyapatite composite graft group(P<0.05). 3. In 2 months, there was no significant differences between the measured forces of DFDB graft group and those of the DFDB and resorbable hydroxyapatite composite graft group. 4. In lightmicroscopic examination, most of the grafted DFDB were transformed into bone in 1 month and a large numbers of hydroxyapatite crystal were observed in DFDB and resorbable hydroxyapatite composite graft group in 1 month. 5. Both group showed no inflammatory reaction in 1 month. And hydroxyapatite crystals had a tight junction without soft tissue invagination when consolidated with newly formed bone. 6. In both groups, newly formed bone showed the partial bone remodeling and the lamellar bone structures and some of reversal lines were observed in 2 months. From the above results, it is suggested that DFDB and resorbable hydroxyapatite composite graft group had a better resistance to compressive force in early stage than DFDB graft group, but there would be no significant difference between two groups after some period. And it is suggested that the early stage of bone formation procedure of DFDB and resorbable hydroxyapatite composite graft group was slight slower than that of DFDB graft group, but there would be no significant difference between two groups after some period.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.525-530
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• 2009

Purpose: The hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) are widely used in the treatment of dyslipidemia for the lowering of cholesterol. And studies about simvastatins have been shown to enhance bone formation in vitro and in vivo in rodents. But some other researchers have reported that there was no anabolic effect abouts simvastatins on bone. The peripheral distribution beyond the liver represents a small fraction of an orally administered dose. We hypothesize that this poor peripheral distribution is the likely reason that simvastatins, yield ambiguous results as anabolic agents. We therefore investigated whether the effects of simvastatins on bone may be enhanced by subcutaneous administration, providing better peripheral delivery of these drugs. Methods: 36 rat unilaterally mandible fractured models were prepared and divided into two groups. The simvastatin treated group where 1 mg/kg of simvastatin was daily injected subcutaneously. The same dose of normal saline was injected on the control group. And 3 rats in each group were sacrificed and taken bone samples in each week. Bone sample was evaluated with tensile strength and histological morphology after 1, 2, 3, 4, 5 and 6 weeks. Results: In simvastatin treated group, the fracture healing process, chondrocyte aggregation, collagen formation and trabecular bone formation was rapidly proceeded than the control group in histologically. The tensile strength of the simvastatin treated group was 1.02, 2.25, 3.95, 4.42, 5.49 and $6.00N/mm^2$ by weeks. The control group data was 0.60, 1.05, 2.17, 3.75, 4.15 and $5.17N/mm^2$ by weeks. The average tensile strength was higher by $1.04N/mm^2$ in simvastatin treated group. Conclusion: The currently available data on the effects of simvastatin on bone has done to confirm the finding that simvastatin helps fracture healing. And the potential for simvastatin to be used as anabolic agents for bone when delivered by the subcutaneous route.

• Nutrition Research and Practice
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• 제8권5호
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• pp.539-543
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• 2014

BACKGROUND/OBJECTIVES: Soy isoflavones are structurally similar to estrogen and bind to estrogen receptors, suggesting that they exhibit estrogenic activities; therefore, they are referred to as phytoestrogens. Fermentation may affect the bioavailability of isoflavones altering soy isoflavone glycosides in the form of aglycones. Thus, this study investigated the effects of fermented soybeans by Rhizopus oligosporus on bone metabolism in both young rats as a pilot test and in ovariectomized (ovx) old rats as a model of menopause. MATERIALS/METHODS: In the pilot test, a total of 24 seven-week-old female Sprague-Dawley (SD) rats were fed one of three diets for a period of four weeks: casein, unfermented soybean product, or fermented soybean product by R. oligosporus. In the ovx rat model, 20-week-old SD rats weighing 260-290 g underwent either sham-operation (n = 10) or bilateral ovariectomy (n = 30) and were then fed the AIN-93M diet for one week. Thereafter, rats were fed sham-casein, ovx-casein, ovx-soybean, or ovx-fermented soybean diet for five weeks. After decapitation, femoral bones were isolated and preserved in 9% formalin for assessment of bone mineral density (BMD), bone mineral content (BMC), and bone-breaking strength (BBS). RESULTS: Ovx rats showed significantly increased weight gain and decreased uterine wet weight. Of particular interest, ovx rats fed fermented soybeans showed increased uterine wet weights compared to control rats. Fermented soybean diet caused a significant increase in plasma 17-${\beta}$ estradiol concentrations in young rats, and 17-${\beta}$ estradiol levels were enhanced in ovx rats to match those of sham-operated ones. Significantly lower femoral BMD and BMC were observed in ovx rats compared to sham-operated controls, whereas bone areas did not differ statistically among the groups. In addition, BBS tended to be increased in ovx rats fed soybeans and fermented soybeans. CONCLUSIONS: Supplementation of fermented soybeans could have preventive and therapeutic effects against osteoporosis in postmenopausal women.

• 한국지역사회생활과학회지
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• 제13권2호
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• pp.53-61
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• 2002

This study is to find out how the 4 types of calcium salt such as calcium carbonate, calcium phosphate, calcium lactate and calcium citrate in soy protein diet, the vegetable protein source, affect the calcium utilization in the body. To do so, calcium, phosphate and creatinine concentration and ALP activity in blood as well as the content of calcium and ash, the length, weight strength, and the calcium utilization in the bone were measured. Four groups of Sprague-Dawley male rats with the weight of around 180g were fed for 3 weeks with the experimental diet. Each group was fed with the isolated soy protein containing 14% of the diet and the above mentioned 4 types of calcium salt as the calcium source. The results are as follows; 1. There were no differences of the feed intake, weight gain, and feed efficiency among groups. 2. ALP activity in blood was sinificantly high in calcium lactate group(P<0.05), but there were no differences of concentration of calcium, phosphates, and creatinine in blood among groups. 3. The weight, calcium content, calcium ratio in ash and the strength of bone were low when calcium lactate was provided(P<0.05). 4. The content of calcium in the liver was high in calcium lactate group and calcium citrate group(P<.0.05). 5. The exceretion of feces was low in calcium lactate group(P<0.05) and the excretion of urine was also relatively low. In addition, the ratio of absorption and the retention of calcium were high(P<0.05). In summary, out of four types of calcium salt such as calcium carbontate, calcium phosphate, calcium lactate and calcium citrate when calcium lactate was provided the ALP activity in blood was high and the weight, calcium content, calcium ratio in ash and the strength of bone were low. In calcium utilization, the ratio of absorption and retention of calcium were high, however it has lower effect than 3 other calcium types in improving weight, the content of calcium and the strength of bone.

• 대한기계학회논문집A
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• 제35권6호
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• pp.583-589
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• 2011

순수한 전기장 하에서의 뼈와 유사한 재료의 절연파괴에 대하여 연구하였다. 일반적으로 뼈와 유사한 재료는 강한 유전강도를 가지는 층과 약한 유전강도를 가지는 층이 서로 평행하게 엇갈려 있는 형태로 구성되어 있다. 뼈와 유사한 재료의 약한 층을 관통하는 전도채널의 성장은 전기장의 집중이 완화되기 때문에 지연된다. 관형채널의 선단에서 전기장의 분포를 유한요소해석을 통해 구하였다. 뼈와 유사한 재료의 절연강도를 J 적분을 사용하여 계산하였고, 절연강도에 영향을 미치는 인자들을 찾아내었다. J 적분은 약한 층에서의 절연파괴 면적이 증가할 수록 작아짐을 보였다. 또한, 약한 층과 강한 층의 유전율의 비가 절연파괴에 큰 영향을 미치는 것으로 나타났다.

• 한국임상수의학회지
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• 제17권1호
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• pp.212-218
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• 2000

Osteoporosis is a bone disease associated with reduced bone mineral density resulting in debilitating bone fractures. The present study was carried out to determine the influence of ovariectomy(OVX) on serum level of sex steroid and bone metabolism, as well as bone mechanical property, in OVX subjects in comparison with controls. Body weight and food intake was significantly increased in OVX subjects than in controls. The serum level of estradiol(E2) was significantly lower in OVX subjects than in controls. The serum level of calcium and alkalin phosphatae were significantly increased in OVX subjects than in controls. The bone strength, based on the three point bending test, was not significantly different. Seven weeks after ovariectomy, the cavities in the bone reached 223% of the normal. In conclusion, seven weeks after ovariectomy osteoporo sis was evidently appeared.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.226.2-226.2
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• 2003

.The healing of a bone defect is complex, and involves a wide range of cellular, molecular, physiological, and biological processes. The main effect of bone substitute is to promote wound healing by induce cell proliferation. Bone defect sites usually are localized below the original bone surface; therefore, space production and maintenance between the membrane and the original bone surface is essential. As a result, membranes must have proper mechanical strength to prevent the collapse of the soft tissue and maintain wound space that permits membranes of poly (L-lactide) (PLLA) were fabricated to provide and maintain sufficient space for bone growth. (omitted)

• 디지털융복합연구
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• 제16권2호
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• pp.375-383
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• 2018

본 연구는 유산소와 저항성 운동이 접목된 복합트레이닝을 비만과 골다공증 진단을 받은 지적장애인 성인에게 12주간 적용한 후 운동의 효과를 알아보기 위해 신체구성검사, 건강관련체력 그리고 골다공증의 변화를 검증하였다. 연구대상들의 운동은 12주간 주2회 유산소운동과 근력 운동을 구성된 복합트레이닝 프로그램을 실시하였다. 유산소운동은 저강도에서 시작하여 점증부하원리를 적용하였고, 저항성 운동은 15회를 반복할 수 있는 강도로 설정하였다. 신체조성과 골밀도는 운동전, 6주, 12주 세 차례 측정하였고, 건강체력평가는 운동전과 운동 후 측정하였다. 체중, 체지방은 운동전에 비해 운동 후 감소하였고, 골밀도는 운동전에 비해 운동 후 증가하였다. 체력요인으로 근력과 근지구력, 유연성이 운동전에 비해 운동 후 개선되었다. 본 연구결과로 12주의 복합트레이닝은 하지근력을 증가시켜 걷기, 달리기 등의 기능을 향상시키고, 건강체력의 향상과 골밀도의 증가를 일으키는 운동임을 확인하였다.

• The Journal of Advanced Prosthodontics
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• 제7권2호
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• pp.115-121
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• 2015

PURPOSE. This study aimed to evaluate the effect of implant thread depth on primary stability in low density bone. MATERIALS AND METHODS. The insertion torque was measured by inserting Ti implants with different thread depths into solid rigid polyurethane blocks (Sawbones) with three different bone densities ($0.16g/cm^3$, $0.24g/cm^3$, and $0.32g/cm^3$). The insertion torque value was evaluated with a surgical engine. The static compressive strength was measured with a universal testing machine (UTM) and the Ti implants were aligned at $30^{\circ}$ against the loading direction of the UTM. After the static compressive strength test, the Ti implants were analyzed with a Measurescope. RESULTS. The Ti implants with deeper thread depth showed statistically higher mean insertion torque values (P<.001). Groups A and group B had similar maximum static compressive strengths, as did groups C and D (P>.05). After the static compressive strength, the thread shape of the Ti implants with deeper thread depth did not show any breakage but did show deformation of the implant body and abutment. CONCLUSION. The implants with deeper thread depth had higher mean insertion torque values but not lower compressive strength. The deep threads had a mechanical stability. Implants with deeper thread depth may increase the primary stability in areas of poor quality bone without decreasing mechanical strength.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권1호
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• pp.55-59
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• 2013

In the oral and maxillofacial area, bone defects are created by various reasons and demand for bone grafts, while dental implant implantation has been increased consistently. To solve these problems, there has been development of autogenous tooth-bone graft material (AutoBT$^{(R)}$, Korea Tooth Bank Co., Korea), and we have collected ground reasons to substitute free autobone graft with this material in clinical use. This autogenous tooth-bone graft material is produced in powder type and block type. Block type is useful in esthetic reconstruction of the defect site and vertical and horizontal augmentation of alveolar bone because this type has high strength value, well maintained shape and is less absorbed. Therefore, the author of this study gained favorable result by grafting the block type autogenous tooth-bone graft material after dental implant implantation on the bone defects of the mandibular molar extraction site. Moreover, the author represents this case with literature review after confirming bone remodeling on the computed tomography image and by histological analysis.