• 대한치과기공학회지
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• 제42권4호
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• pp.348-354
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• 2020

Purpose: Zirconia is differentiated from other ceramics because of its high resistance to corrosion and wear, excellent flexural strength (900~1400 MPa), and high hardness. Dental zirconia with proven mechanical/biological stability is suitable for the manufacture of implants. However, there are limited in vivo studies evaluating stress distribution in zirconia compared with that in titanium implants and studies analyzing finite elements. This study was conducted to evaluate the stress distribution of the supporting bone surrounding zirconia and titanium implants using the finite element analysis method. Methods: For finite element analysis, a single implant-supported restoration was designed. Using a universal analysis program, eight occlusal points were set in the direction of the occlusal long axis. The occlusal load was simulated at 700 N. Results: The zirconia implant (47.7 MPa) von Mises stress decreased by 5.3% in the upper cortical bone compared with the titanium implant (50.2 MPa) von Mises stress. Similarly, the zirconia implant (20.8 MPa) von Mises stress decreased by almost 4% in the cancellous bone compared with the titanium implant (21.7 MPa) von Mises stress. The principal stress in the cortical and cancellous bone exhibited a similar propensity to von Mises stress. Conclusion: In the supporting bone, the zirconia implant is able to reduce bone resorption caused by mechanically transferred stress. It is believed that the zirconia implant can be a potential substitute for the titanium implant by reinforcing aesthetic characteristics and improving stress distribution.

• 대한족부족관절학회지
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• 제21권1호
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• pp.7-11
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• 2017

Purpose: We retrospectively analyzed the radiographic and clinical results after the first ray of forefoot osteotomy using low profile wedge plate without additional cancellous bone grafting for pes planus correction. Materials and Methods: Twenty-four patients were enrolled in this study. Medial cuneiform opening wedge osteotomy was performed in 12 patients (Cotton osteotomy, group C) and first metatarsal base osteotomy was performed in 12 patients (group MT). Results: On average, the wedge size was 5.61 mm (5~6 mm). The mean time to radiographic union was 3.18 and 3.27 months in groups C and MT, respectively. Postoperative talonavicular coverage angle, talo-first metatarsal angle (anteroposterior), talo-first metatarsal angle (lateral), talo-calcaneal angle (lateral), medial cuneiform height, and American orthopaedic foot, as well as ankle society midfoot scale were significantly improved in both groups. Nonunion, delayed union or fixation failure was not presented in our series. Conclusion: We have shown that low profile wedge plate was effective in the case of first ray forefoot osteotomy for pes planus correction without any additional cancellous bone grafting.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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• pp.373-376
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• 2002

Most previous studies using ultrasound for osteoporosis diagnosis have employed ultrasound in a frequency range of 0.2-1 MHz. In this study, acoustic properties of the 12 defatted bovine cancellous bone specimens were investigated in vitro. Speed of sound (SOS) and broadband ultrasonic attenuation (BUA) were measured using three matched pairs of transducers with the center frequencies of 1, 2.25, and 3.5 MHz, respectively, in order to cover a broad frequency range of 0.5-2 MHz. The relative orientation between ultrasonic beam and bone specimens was the mediolateral (ML) direction of the bovine tibia. SOS showed significant linear positive correlations with apparent density for all three pairs of transducers of 1 MHz, 2.25 MHz, and 3.5 MHz, respectively. BUA showed relatively weak correlations with apparent density for the pairs of transducers of 1 MHz and 2.25 MHz. Furthermore, in the measurement with the pair of 3.5 MHz transducers, BUA was independent of apparent density. SOS and BUA were only weakly correlated with each other. The linear combination of SOS and BUA showed significant correlations with apparent density. These results suggest that the frequency range up to 1.5 MHz may be also useful in the osteoporosis diagnosis.

• 대한기계학회논문집A
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• 제27권7호
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• pp.1103-1109
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• 2003

An adaptive bone remodeling is simulated by using the cellular automata (CA) method. It is assumed that bone tissue consist of bone marrow, osteoclast, osteoblast cell or osteoprogenitor cell. Two types of local rule are adopted; those are the metabolism rule and adaptive bone formation rule. The metabolism rule is based on the interactions of cells and the bone formation rule is based on the adaptation against the mechanical stimulus. The history of load and memory of mechanical stimulus are also considered in the local rules. As a result, the pattern of distribution of the bone tissue is dynamically adequate and it is similar to intact cancellous bone.

• 한국산학기술학회논문지
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• 제12권5호
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• pp.2197-2202
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• 2011

본 논문에서는 중공을 가지는 짧은 치과용 임플란트의 생체역학적인 특성을 3차원 유한요소해석을 통하여 분석하였다. 고려된 치과용 짧은 임플란트는 골유착성을 향상시키기 위해 트리패닝 드링 등에 의해 남겨진 치골과 결합될 수 있는 중공부를 가진다. 연구를 위해 Bicon사의 길이가 짧은 임플란트를 기본 모델로 삼아 중공부가 임플란트 주변 치골의 응력분포에 주는 영향을 분석하였다. 중공부 길이, 직경 및 나사산 등의 형상변수에 따른 반복적인 유한 요소해석을 효과적으로 수행하기 위하여 ANSYS APDL을 이용하여 매개변수화된 유한요소모델을 구성하였다. 해석결과 중공부를 가지는 경우 특히 경사하중 하에서 해면골에서 발생하는 최대응력값이 크게 감소하였으며, 중공부의 형태가 해면골에서의 응력분포에 큰 영향을 주는 것으로 나타났다.

• 대한한방부인과학회지
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• 제15권4호
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• pp.17-31
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• 2002

Objective : This study was carried out to investigate the effects of the hormones and cytokines associated with bone metabolism in ovariectomized rats. Method : Twenty-four Female-Sprague-Dawley rats were divided into sham operated(normal) group, ovariectomized(control)group, ovariectomized and treated with extract Caraganae Sinicae Radix(treated) group. Each group was investigated the changes of body weight at 3,5,7weeks after treatment, and femur weight, femur/body weight, thickness of compact bone of body of femur, area of cancellous bone of distal epiphysis of femur, serum estrogen, serum calcitonin, serum parathormone, serum Tumor Necrosis $Factor-{\alpha}$, serum $lnterleukin-1{\beta}$ at 7weeks after treatment. The results were summerized as follows; 1. The treated group showed significant change in body weight compared with the control group at 5,7weeks after treatment. 2. The treated group revealed significant increases in femur/body weight compared with the control group. 3. The treated group showed a little thicker compact bone of body of femur than the control group. 4. The area of cancellous bone of distal epiphysis of femur in treated group was increased significantly compared with control group. 5. The level of serum estrogen showed no change compared with control group. 6. The level of serum calcitonin showed no change compared with control group. 7. The level of serum parathormone was decreased in treated group significantly compared with control group. 8. The level of serum $TNF-{\alpha}$ was decreased in treated group significantly compared with control group. 9. The level of serum $interleukin-1{\beta}$ showed no change compared with control group. The results indicate that Caraganae Sinicae Radix inhibits bones resorption in ovariectomized rats by it's lowering effects on serum parathormone and $TNF-{\alpha}$.

• 한국임상수의학회지
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• 제30권2호
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• pp.127-130
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• 2013

13년령의 4.2 kg 암컷 푸들이 하악의 병적 골절 후 지역병원에서 받은 양측성 하악 수술의 실패로 내원하였다. 수술은 2.0-mm miniplates/screws, 돼지해면질골 및 흡수성 막을 사용해 시행되었다. 수술 후 1일, 1, 4, 8, 12주에 예후를 평가하였다; 치아 부정교합, 골절 불유합, 또는 연부조직 감염의 징후는 보이지 않았다. 그러나 1년 후 장기간 검진에서 콜라겐 막을 사용하지 않았던 왼쪽 하악골절부위에 불유합이 관찰되었다. 따라서 노령견에서 하악골 불유합의 치유에 돼지해면골과 흡수성 막을 함께 사용하는 것은 효과적이라 생각된다.

• 대한골관절종양학회지
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• 제10권1호
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• pp.13-21
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• 2004

목적: 골수에서 분리한 기질 세포를 단독으로 또는 동종 망상골과 함께 이식하여 치료했던 양성 골 병변 소파 후 발생한 골 결손에 대한 치료 결과를 보고 하고자 한다. 대상 및 방법: 1996년 7월 이래 장관골 양성 골 병변에 대해 병변이 작거나 소아여서 소파술과 함께 자가 골수 기질 세포를 단독으로 이식하였던 2명 3례와, 자가 골수 기질 세포와 동종 망상골 이식을 병행하여 치료하였던 6명 6례 등 총 8명 9례를 대상으로 수술 후 임상증상의 해소, 신생 골 형성 및 주변 정상골과의 유합 과정을 추시하였다. 남자가 6례, 여자가 2례였으며 평균 연령은 24세(8세~47세)였다. 조직학적 진단은 섬유성 골 이형성증이 5례로 많았고, 단순 골 낭종 2례, 연골모세포종과 섬유성 피질 결손이 각각 1례씩 이었다. 수술 후 평균 추시기간은 16.3개월(3개월~84개월) 이었다. 결과: 수술 전 병소 부위에 통증을 호소했던 4례 모두에서 술 후 2주 이내에 증상이 소실되었으며, 수술 후 촬영한 단순 방사선 사진 상 약 4주경부터 병변 부위에 신생 골 형성이 관찰되고 약 8주경에는 골 결손 부위가 신생 골로 충전되고 주변 정상골과 유합된 소견을 보였다. 합병증으로는 1례에서 술 후 3주에 병소 부위를 통과하는 골절이 발생했으며, 단순 골 낭종 1례에서 술 후 5개월에 병소가 재발하였다. 결론: 장관골 양성 골 병변에 대해 소파 후 골수에서 분리한 골수 기질 세포를 단독으로 또는 동종 망상골과 함께 이식할 때 빠른 치유과정을 보여, 비록 단 기간의 추시 결과이기는 하나 골수 기질 세포 이식술이 향후 골 낭종이나 양성 골 병변의 치료에 크게 이용될 수 있을 것으로 보인다. 골 낭종 수술 후 재발 원인은 낭종내벽 섬유조직의 불완전 소파의 결과로 보이며, 골절 발생 가능성이 높은 대퇴골 전자간 골 낭종 등에 대하여는 금속판 등을 이용한 예방적인 고정이 필요할 것으로 판단되었다.

• Clinics in Shoulder and Elbow
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• 제20권1호
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• pp.42-45
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• 2017

One of the most important factors leading to a successful healing of rotator cuff tear is good bone quality to secure the suture anchor in the bone for a stable fixation. However, rotator cuff tear are commonly found in elderly patients, and their proximal humerus often shows osteoporosis or cystic lesions. Especially when the transosseous repair prevails for a torn rotator cuff, a weak metaphyseal cancellous bone is often the case, which associated with difficulty in stable fixation of the lateral row suture anchor. In this situation, we were able to augment the lateral row fixation with polymethylmethacrylate bone cement. Although there is a concern of disturbance in the blood flow and healing potential, our case showed good clinical results with respect to healing. If we suspect a weak fixation of the lateral row suture anchor, bone cement seems to be a good option for augmentation.

• Archives of Plastic Surgery
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• 제38권3호
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• pp.222-227
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• 2011

Purpose: Autogenous particulate bone grafting is a type of autogenous bone graft that consists of small particles of cortical and cancellous bone. Autogenous particulate bone grafting has been used for calvarial bone defect after calvarial defect of craniosynostosis and prevention of temporal depression after fronto-orbital advancement. The results were followed up and studied for effectiveness of autogenous calvarial particulate bone grafting. Methods: Cranial vault remodeling and fronto-orbital advancement was performed for six craniosynostosis patient from August 2005 to October 2007. Autogenous particulate bone grafting was harvested from endocortex of separated cranial vault and if insufficient, from extocortex of occipital region using Hudson brace & D'Errico craniotomy bit and was grafted on the calvarial bone defect of cranial vault and temporal hollow. Fibrin glues were added to the harvested particulated bone for adherence and shaping of paticles. Results: Autogenous particulate bone grafting was followed-up at least longer than I year. The calvarial bony defects following primary cranial remodeling were successfully covered and postoperative temporal depressions after fronto-orbital advancement were also well prevented by grafted particulated bone. Conclusion: Autogenous calvarial particulate bone graft can be harvested in infants and young children with minimal donor site morbidity. It effectively heals cranial defects in children and during fronto-orbital advancement reduces the prevalence of osseous defects independent of patient age. It's easy and effective method of reconstruction of calvarial defect.