• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권2호
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• pp.55-62
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• 2013

Bone tissue engineering is one of the important therapeutic approaches to the regeneration of bones in the entire field of regeneration medicine. Mesenchymal stem cells (MSCs) are actively discussed as material for bone tissue engineering due to their ability to differentiate into autologous bone. MSCs are able to differentiate into different lineages: osteo/odontogenic, adipogenic, and neurogenic. The tissue of origin for MSCs defines them as bone marrow-derived stem cells, adipose tissue-derived stem cells, and, among many others, dental stem cells. According to the tissue of origin, DSCs are further stratified into dental pulp stem cells, periodontal ligament stem cells, stem cells from apical papilla, stem cells from human exfoliated deciduous teeth, dental follicle precursor cells, and dental papilla cells. There are numerous in vitro/in vivo reports suggesting successful mineralization potential or osteo/odontogenic ability of MSCs. Still, there is further need for the optimization of MSCs-based tissue engineering methods, and the introduction of genes related to osteo/odontogenic differentiation into MSCs might aid in the process. In this review, articles that reported enhanced osteo/odontogenic differentiation with gene introduction into MSCs will be discussed to provide a background for successful bone tissue engineering using MSCs with artificially introduced genes.

• Journal of Chest Surgery
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• 제26권6호
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• pp.470-474
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• 1993

A clinical evaluation was performed on 56 patients[ 60 cases ] of open thoracotomy in spontaneous pneumothorax who were admitted and treated at department of Thoracic and Cardiovascular Surgery, Chung Ang University, Yong San Hospital during the past 3 years from March 1990 to February 1993. The results were as follows. 1. The sex ratio was male predominence [ M:F = 7:1 ]. 2. The most common age group were 2nd, 3rd decades. 3. The most common chief complaints were dyspnea and chest pain [46.3% ]. 4. The etiologic factors of spontaneous pneumothorax were primary spontaneous pneumothorax [ 78.3%], secondary tuberculosis [ 18.3%], and others [ 3.4% ]. 5. The site of spontaneous pneumothorax was 50% in right, 40% in left, and 10% in both. 6. The state of activity on attack was almost in the usual life [ 98.3% ]. 7. Average height was 172.5 $\pm$ 5.39 cm in male and 164.0 $\pm$ 3.51 cm in female, average weight was 59.1 $\pm$ 7.06 kg in male and 52.0 $\pm$ 4.97 kg in female. 8. The common indications of open thoracotomy were recurrence [ 34.4% ] and persistent air leakage [ 17.8% ]. 9. The operative procedures were bullectomy [ 73.3% ], partial resection [ 11.7% ], lobectomy [ 11.7% ], and others [ 3.3% ]. 10. The most frequent location of bulla or bleb were apical segment of RUL [ 43.3 % ] and apicoposterior segment of LUL [ 40.0% ]. 11. The number of visible bulla or bleb were mainly 1 to 5, and size was about 1 to 3 cm.

• Restorative Dentistry and Endodontics
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• 제47권1호
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• pp.2.1-2.11
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• 2022

Objectives: This study investigated the impact of micro-computed tomography (micro-CT)-based voxel size on the analysis of material/dentin interface voids and thickness of different endodontic cements. Materials and Methods: Following root-end resection and apical preparation, maxillary premolars were filled with mineral trioxide aggregate (MTA), Biodentine, and intermediate restorative material (IRM) (n = 24). The samples were scanned using micro-CT (SkyScan 1272; Bruker) and the cement/dentin interface and thickness of materials were evaluated at voxel sizes of 5, 10, and 20 ㎛. Analysis of variance and the Tukey test were conducted, and the degree of agreement between different voxel sizes was evaluated using the Bland and Altman method (p < 0.05). Results: All materials showed an increase in thickness from 5 to 10 and 20 ㎛ (p < 0.05). When evaluating the interface voids, materials were similar at 5 ㎛ (p > 0.05), while at 10 and 20 ㎛ Biodentine showed the lowest percentage of voids (p < 0.05). A decrease in the interface voids was observed for MTA and IRM at 20 ㎛, while Biodentine showed differences among all voxel sizes (p < 0.05). The Bland-Altman plots for comparisons among voxel sizes showed the largest deviations when comparing images between 5 and 20 ㎛. Conclusions: Voxel size had an impact on the micro-CT evaluation of thickness and interface voids of endodontic materials. All cements exhibited an increase in thickness and a decrease in the void percentage as the voxel size increased, especially when evaluating images at 20 ㎛.

• 대한치과보철학회지
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• 제56권1호
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• pp.8-16
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• 2018

목적: 본 연구의 목적은 디지털 소프트웨어를 이용하여 제작된 수술용 스텐트를 이용하여 지지 형태에 따른 수술용 스텐트의 정확성을 분석하는 것이다. 재료 및 방법: 총 5세트의 치아모형에 대하여 양측에 지대치가 있는 치아지지형 무치악 모델과 근심에만 지대치가 있는 치아-조직 지지형 무치악 모델을 제작하였다. 모델을 스캐닝을 시행하고, 전산화 단층 촬영을 실시하여 In2Guide 소프트웨어를 이용하여 전산화 단층 촬영술의 정보와 모델 스캐닝 정보를 중첩하여 임플란트 고정체(USII, $4{\times}10mm$, Osstem, Seoul, Korea)에 대한 가상적인 위치배열을 실시하고 수술용 스텐트 제작하였다. DMAX 수술 키트을 사용하여 임플란트 고정체를 식립하였다. 식립후 전산화 단층 촬영을 실시하여 찍어 술전에 계획된 임플란트와 실제 식립된 임플란트 사이에 오차(angle difference, coronal difference, apical difference)를 측정하여 통계분석을 시행하였다. 결과: 악궁에 따른 정확도 결과에서 하악이 전반적으로 각도, 길이오차의 값이 작게 나타났으나 이는 통계적 유의성이 없었다. 스텐트의 지지 형태에 따른 정확도 결과에서 치아지지형 스텐트가 치아-조직지지형 스텐트보다 길이오차와 각도오차의 값이 통계적으로 유의하게 작은 값을 보였다. 결론: 악궁(상악, 하악)은 수술용 스텐트의 정확도에 영향을 미치지 않았으며, 치아 지지형 스텐트는 치아-조직지지형 스텐트보다 더 적은 오차를 보여 주었다.

• Journal of Chest Surgery
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• 제38권5호
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• pp.371-376
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• 2005

배경: 저자는 원발성 자연 공기가슴증 환자에서 고식적인 비디오흉강경하 쐐기절제술이 흉강경을 이용한 변형된 소절개술식보다 우수한가를 결정할 목적으로 후향적으로 연구를 하였다. 대상 및 방법: 원발성 자연 공기가슴증을 보인 $14\~35$세 사이의 160명의 환자를 대상으로 하였다. 환자는 수술기법과 수술 접근법에 의해서 고식적인 흉강경하 쐐기절제술군(A군: 80예)과 흉강경을 이용한 변형된 소절개술식을 이용한 군(B군: 80예)으로 분류하였다. 모든 환자에서 술 후 늑막강 첨부의 찰과상과 탈크 도포를 수행하였다. 이 연구는 수술시간, 수술 후 사용한 진통제의 사용일수, 수술 첫날 공기누출이 없는 수, 흉관 삽관일과 병원 입원일, 그리고 술 후 합병증, 추적기간 동안의 만성 흉통과 일상생활로 복귀할 때까지의 기간 그리고 또한 추적기간 동안에 수술동측에서의 재발을 평가하였다. 결과: 양 군사이에서 연구한 평가요소 중 어느 것에서도 의의 있는 차이는 없었다. 결론: 고식적인 비디오 흉강경하 쐐기절제술과 흉강경을 이용한 변형된 소절개술식은 원발성 자연 공기가슴증 환자의 수술적 치료에 있어서 유사한 결과를 야기하였다. 합병증의 발생률도 낮고, 통각도 장기 추적동안에 받아들일 만 하였다. 따라서 흉강경을 이용한 변형된 소절개술식 또한 가치 있는 대체수술 기법으로 보인다.

• Journal of Periodontal and Implant Science
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• 제33권4호
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• pp.693-703
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• 2003

The present study evaluated the effects of guided tissue regeneration using xenograft material(deproteinated bovine bone powder), with and without Calcium sulfate membrane in beagle dogs. Contralateral fenestration defects (6 ${\times}$ 4 mm) were created 4 mm apical to the buccal alveolar crest of maxillary premolar teeth in 5 beagle dogs. Deproteinated bovine bone powders were implanted into fenestration defect and one randomly covered Calcium sulfate membrane (experimental group). Calcium sulfate membrane was used to provide GTR. Tissue blocks including defects with soft tissues which were harvested following four & eight weeks healing interval, prepared for histo-phathologic analysis. The results of this study were as follows, 1. In control group, at 4 weeks after surgery, new bony trabecular contacted with interstitial tissue and osteocytes lie cell were arranged in new bony trabecule. Bony lamellation was not observed. 2. In control group , at 8 weeks after surgery, scar-like interstitial tissue was filled defect and bony trabecule form lamellation. New bony trabecular was contacted with interstitial tissue but defect was not filled yet. 3. In experimental group, at 4 weeks after surgery, new bony trabecular partially recovered around damaged bone. But new bony trabecule was observed as irregularity and lower density. 4. In experimental group, at 8 weeks after surgery, lamella bone trabecular developed around bone cavity and damaged tissue was replaced with dense interstitial tissue. In conclusion, new bone formation regenerated more in experimental than control groups and there was seen observe more regular bony trabecular in experimental than control groups at 4 weeks after surgery. In control group, at 8 weeks after surgery, the defects was filled with scar-like interstitial tissue but, in experimental group, the defects was connected with new bone. Therefore xenograft material had osteoconduction but could not fill the defects. We thought that the effective regeneration of periodontal tissue, could be achieved using GTR with Calcium sulfate membrane.

• Archives of Plastic Surgery
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• 제36권5호
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• pp.531-537
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• 2009

Purpose: Alveolar bone grafting has become an essential process in the treatmemt of alveolar cleft patient for stabilization of the maxillary arch, elimination of oronasal fistula, the reconstruction of the soft tissue nasal base support, and creation of bony support for tooth eruption for implant. The use of Autologous iliac cancellous bone is preferable because of the adequate quantity and high osteoinductive potential. However, even with iliac bone, insufficient osteoregeneration and absorption occur due to several factors such as the patient's age, cleft width, functional stress, and others. In order to increase osteoregeneration where the iliac bone is placed, the present study is associated with bone marrow aspirate (BMA). The experimental study evaluated the efficacy of osteoregeneration in normal cleft rabbits when alveolar bone grafting was performed with autologous iliac corticocancellous bone. Methods: Twenty - four New Zealand White rabbits were divided randomly into 2 groups (BMA, control). All animals underwent harvesting of corticocancellous bone graft from the right posterior iliac crest via standard surgical technique. $1m{\ell}$ of BMA were obtained by scraping the needle and aspirate with $10m{\ell}$ syringe from the contralateral iliac bone wall. The muco - periosteal flap on the palate was elevated. A mixture of Equal bone's volumes with BMA and saline as its control was inserted into the cleft. Animals were sacrificed at 2, 4, and 8 weeks and maxilla was harvested for dental peri - apical X-ray, bone matrix density (BMD),and histologic analysis. Result: BMD of regenerated bone to the cleft in the rabbits was higher than that of the control rabbits. X-ray, histologic analysis showed that increased osteoregeneration and low absorption rate were observed in the BMA group. Conclusion: Our experimental study showed BMA enhanced the osteoregeneration and survival rate of alveolar bone grafting. BMA is easy to extract & cost - time effective. So it can be an effective enhancers for bone grafting mixtures.

• Journal of Chest Surgery
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• 제32권2호
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• pp.185-188
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• 1999

폐에 발생한 거세포암종은 대세포암의 일종의 변형으로 현미경상 전체세포중 10% 이상의 거대한 다형, 다핵의 거세포종으로 구성되어 있으며, 중성구가 종양세포내로 들어가는 세포내행동(Emperipolesis)이 특징적인 소견이다. 국소재발과 초기전이를 잘 일으키는 고도의 악성종양으로 예후는 불량하나, 수술후 보조화학요법과 방사선요법에 의해 생존률을 높일 수 있다는 보고들이 있다. 2달간의 객혈을 주소로 내원한 46세의 남자환자가 단순 흉부 X선 검사와 전산화 단층촬영상 우상엽 첨부에 5 cm크기의 종괴가 발견되었고, 수술을 위한 검사도중 관상동맥조영술상 좌전하행지에 협착소견이 보여 경피적 경혈관혈관확장술을 시행하였다. 4주후 우상엽 절제술을 시행후 병리조직상 거세포암종으로 확인되어, 보조화학요법과 방사선요법을 받았다.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.407-417
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• 1995

In order to evaluate the effect of platelet-derived growth factor(PDGF-BB) and guided tissue regeneration(GTR) technique on the regeneration of destructed periodontal tissue,intentional through-and-through furcation defects(4mm in height) were made on both mandibular 2nd and 4th premolars of 8 adult male dogs(30-40lb). Experimental group 1 was composed of the premolars that were treated by only topical application of PDGF-BB with 0.05M acetic acid without any barrier membrane. Experimental group 2 was composed of the premolars that were treated by GTR with expanded polytetrafluoroethylene membrane(ePTFE : Gore-tex periodontal material, USA). Experimental group 3 was composed of the premolars that were treated by GTR with ePTFE after topical application of PDGFBE. Control group was composed of the premolars that were treated by coronally positioned flap operation only without use of PDGF-BB and ePTFE membrane. All ePTFE membranes were carefully removed 4 weeks after regenerative surgery, and all experimental animals were sacrificed 8 weeks after regenerative surgery. The light microscopic findings were as follows ; (1) In experimental group 1, rapid new bone formation along the-root surface with multiple ankylosis and root resorption by multinucleated giant cells, and dense connective tissue in the central portion of the furcation defects were observed. (2) In experimental group 2, it was observed that the furcation defects were filled with newly formed bone, Sharpey's fibers were embedded into new cementum on root dentin of furcation fornix area, but the central portion and the area under furcation fornix were still filled with dense connective tissue. (3) In experimental group 3, the furcation defects were regenerated with newly formed dense bone and regular periodontal ligament with Sharpey's fibers embedded into newly formed cementum and bone underneath fornix area. (4) In control group, unoccupied space, apical migration of epithelium, dense infiltration of inflammatory cells in subepithelial connective tissue in relation to heavy plaque accumulation, and root resorption by inflammatory reaction were shown, but any new cementum formation on resorbed dentin surface could not be observed. The present study demonstrated that the combined therapy of PDGF-BB and GTR could enhance the regeneration of destructed periodontal tissue.

• Journal of Periodontal and Implant Science
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• 제30권1호
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• pp.167-180
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• 2000

The present study evaluated the effects of guided tissue regeneration using biodegradable membrane, with and without calcium-phosphate thin film coated deproteinated bone powder in beagle dogs. Contralateral fenestration defects(6 × 4 mm) were created 4 mm apical to the buccal alveolar crest on maxillary canine teeth in 5 beagle dogs. Ca-P thin film coated deproteinated bone powder was implanted into one randomly selected fenestration defect(experimental group). Biodegradable membranes were used to provide bilateral GTR. Tissue blocks including defects with overlying membranes and soft tissues were harvested following a four- & eight-week healing interval and prepared for histologic analysis. The results of this study were as follows. 1.......The regeneration of new bone, new periodontal ligament, and new cementum was occurred in experimental group more than control group. 2.......The collapse of biodegradable membranes into defects were showed in control group and the space for regeneration was diminished. In experimental group, the space was maintained without collapse by graft materials. 3........In experimental group, the graft materials were resorbed at 4 weeks after surgery and regeneration of bone surrounding graft materials was occurred at 8 weeks after surgery. 4.......Biodegradable membranes were not resorbed at 4 weeks and partial resorption was occurred at 8 weeks but the framework and the shape of membranes were maintained. No inflammation was showed at resorption. In conclusion, the results of the present study suggest that Ca-P thin film coated deproteinated bone powder has adjunctive effect to GTR in periodontal fenestration defects. Because it has osteoconductive property and prohibit collapse of membrane into defect, can promote regeneration of much new attachment apparatus.