• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.622-627
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• 2012

During helicopter rotor system development process, whirl tower test is conducted basically. For conducting whirl tower test during bearingless hub development process, design new blade or using existing blade with repair or remodeling. Because simple shape and efficient aerodynamic characteristic, BO-105 blade is used for hub system development widely. Originally BO-105 blade is used for hingeless hub, ho flap stiffness and lag stiffness on blade root area is relatively low. So applying BO-105 blade to bearingless hub whirl tower test, root area have to be reinforce. In this process, blade root area's section property will be changed. In this paper, suggest reinforcement method of BO-105 blade root area and study dynamic characteristic of bearingless rotor system with reinforcement BO-105 blade.

• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.17-32
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• 1995

The purpose of this study was to examine the response of periradicular tissues to amalgam, IRM, Ketac-silver and MTA(Mineral trioxide aggregate) used as a root end fillings. The lower third and fourth premolars of 5 mongrel dogs were used. Each root was resected, followed by root end fillings with experimental materials. The animals were sacrificed after 16 weeks and radiographic and histologic results were evaluated. The results were as follows : 1. Severe inflammation around apex and disruption of cortical were noted in relation to the amalgam. 2. With IRM, there was severe infiltration of inflammatory cells around filling material, but healing of cortical bone was noted. 3. With Ketac-silver, mild inflammation and thick band of fibrous connetive tissue around filling material were seen, with a cortical bone healing. 4. In case of MTA, complete regeneration of cortical bone was seen, and free MTA was surrounded with newly formed bone tissue.

• 대한소아치과학회지
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• 제25권1호
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• pp.1-18
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• 1998

The purpose of this study was to analyze comparatively the effect of various root pretreatments prior to delayed replantation. Total 6 beagle dogs were used for the experiment and 8 teeth per each animal were treated by several prepared regimens before replantation. After 3 & 6 weeks of experimental periods, animals were sacrificed by perfusion method. The results obtained from the present study can be summarized as follows: 1. All root pretreatment regimen used in this experiment showed effectiveness in the periodontal repair of delayed replanted teeth. 2. The teeth treated by the regimen of stannous fluoride combined with tetracycline revealed more favorable tissue response and less frequent root resorption or ankylosis than other groups. 3. The long term effect of Group IV-regimen seems to be worth further study since the result at 6-weeks showed the significant progress in periodontal healing when compared to 3-week result which was not indicated in any other group

• Journal of Chest Surgery
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• 제56권6호
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• pp.445-448
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• 2023

A 25-year-old man returned to Seoul National University Children's Hospital with mild dyspnea on exertion. He had undergone an arterial switch operation at 1 month after birth to correct a complete transposition of the great arteries and a ventricular septal defect. When the patient was 15 years old, dilatation of the neo-aortic sinus and annulus was first identified; since then, it had gradually increased. Given the young age of the patient and the degree of aortic regurgitation (AR), which was mild to moderate, we opted to perform a valve-sparing neo-aortic root replacement with aortic valve repair. Postoperative echocardiography showed successful reductions in the sizes of the aortic sinus and annulus, with only mild AR remaining.

• Restorative Dentistry and Endodontics
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• 제43권2호
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• pp.17.1-17.7
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• 2018

Iatrogenic perforations negatively impact the outcome of endodontic treatments. Studies on prognostic factors showed that perforations in the coronal third of the root with periodontal pocket formation have an unfavorable prognosis. A 36-year-old female was referred for endodontic evaluation of tooth #13 with a history of an iatrogenic perforation, happened 3 years ago. There was a sinus tract associated with perforation, 10 mm probing on the mesial and mesio-palatal, bleeding on probing, radiolucent lesion adjacent to the perforation and complete resorption of the interdental bone between teeth #13 and #12. After the treatment options were discussed, she chose to save the tooth. The tooth was accessed under rubber dam isolation, the perforation site was cleaned and disinfected using 0.5% sodium hypochlorite and sealed with calcium-enriched mixture cement. Eighteen months after treatment the tooth was functional and asymptomatic. The probing depths were normal without bleeding on probing. Radiographically, the interdental crestal bone formed between teeth #13 and #12. Despite all negative prognostic factors in this case (i.e., perforations in the coronal third, pocket formation, and radiolucent lesion), healing was unexpectedly achieved via non-surgical repair of the perforation. Further research on biological aspects of healing in the periodontium following iatrogenic perforations are recommended.

• Journal of Chest Surgery
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• 제51권1호
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• pp.61-63
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• 2018

We report the case of a patient with mitral regurgitation complicated by type B dissection and Marfan syndrome (MFS) who was managed successfully with minimally invasive mitral valve repair. Without type A aortic dissection or aortic root dilation, MFS patients may develop mitral valve regurgitation, as in this case, and need valve surgery to improve their symptoms and long-term survival. However, it is not clear that a full sternotomy and prophylactic aortic surgery are necessary. Although retrograde perfusion to the dissected aorta is controversial, our approach minimizes the risk of future anticipated aortic surgery in MFS patients.

• 대한관절경학회지
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• 제16권2호
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• pp.153-159
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• 2012

목적: 본 연구의 목적은 슬관절 내측 반월상 연골판 후방 부착부 파열 환자에 대해 관절경적 견인 봉합술을 시행한 후 임상적 및 방사선학적 5년 추시 결과를 보고하고자 한다. 대상 및 방법: 2001년 1월부터 2005년 5월까지 본원에서 내측 반월상 연골판 후방 부착부 파열로 진단받고 관절경적 견인 봉합술을 시행한 환자 중 5년 이상 추적 관찰이 가능하였던 30예를 대상으로 하였다. 평균 추시 기간은 76개월(60-90개월)이었다. 임상적 결과는 Lysholm knee score로 확인하였고 방사선학적 결과는 단순 방사선 사진을 이용한 Kellgren-Lawrence 분류를 이용하였으며, 전예에서 2차 관절경 수술을 시행하였다. 외상, 비만, 내반 변형 및 수술 시기 등과 임상적 결과를 비교 분석하였다. 결과: 임상적 결과는 수술 전 Lysholm knee score 평균 55점에서 5년 추시 시 평균 86점으로 호전을 보였고, 방사선학적 추시 검사 결과 23예에서 관절 간격의 유지 및 호전 소견 보였으며, 7예에서 관절 간격이 감소되는 등의 퇴행성 변화가 있었고, 그 중 1예에서 골 관절염의 진행 소견으로 추후 인공 관절 치환술을 시행하였다. 결론: 관절경적 견인 봉합술을 시행하여 최소 5년 추시에서 27예(90%)에서 양호 이상의 좋은 결과를 얻었으며 내반 각도가 클수록 임상적으로 호전되는 정도는 유의하게 낮았다.

• Journal of Chest Surgery
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• 제34권7호
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• pp.557-558
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• 2001

순턴향대학 턴안병원 흥부외과에서는 Stan$\ulcorner$old type A급성 대동맥 박리증, 대동맥 근부 동맥류 및 대동맥 폐쇄부전을 보인 45세 말판 증후군 환자에게 24m Hemashield 도관을 이용하여 Yacoub-David 수술법에 의한 대동맥 근부 개형술(aortic root remodeling procedure)을 시행하였다 수술은 환자의 대동맥 판막을 보존하면서 대동맥등을 포함한 대동맥 근부의 질병조직을 모두 제거한 후, 글이 발살바동 모양으로 3등분된 인조혈관으로 대동맥등으로부터 상행 대동맥가지 대치하는 방법으로 하였다. 환자는 수술 후 양호한 회복을 보였고 대 동맥 판막의 역류는 완전히 교정되었다.

• Journal of Chest Surgery
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• 제48권5호
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• pp.364-367
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• 2015

Cardiovascular involvement in cases of Behcet's disease is a rare but life-threatening condition, and prosthetic valve detachment is a frequent and serious complication attributable to Behcet's disease following the surgical repair of aortic regurgitation. We report the case of a patient with Behcet's disease presenting with contained aortic rupture around the aortic root. The patient had previously undergone aortic valve surgery three times due to recurrent prosthetic valve detachment. An emergency operation was performed, consisting of aortic root replacement (ARR) using a composite valved conduit and the replacement of the hemiarch. ARR may be an appropriate surgical option for patients with Behcet's disease in order to prevent recurrence of the disease.

• Restorative Dentistry and Endodontics
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• 제37권4호
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• pp.188-193
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• 2012

Mineral trioxide aggregate (MTA) was developed in early 1990s and has been successfully used for root perforation repair, root end filling, and one-visit apexification. MTA is composed mainly of tricalcium silicate and dicalcium silicate. When MTA is hydrated, calcium silicate hydrate (CSH) and calcium hydroxide is formed. Formed calcium hydroxide interacts with the phosphate ion in body fluid and form amorphous calcium phosphate (ACP) which finally transforms into calcium deficient hydroxyapatite (CDHA). These mineral precipitate were reported to form the MTA-dentin interfacial layer which enhances the sealing ability of MTA. Clinically, the use of zinc oxide euginol (ZOE) based materials may retard the setting of MTA. Also, the use of acids or contact with excessive blood should be avoided before complete set of MTA, because these conditions could adversely affect the hydration reaction of MTA. Further studies on the chemical nature of MTA hydration reaction are needed.