• KSBB Journal
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• 제21권6호
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• pp.439-443
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• 2006

조직공학에서 생체재료의 생체적합성과 조직재생능력은 생체재료가 생체에 적합한지를 판단하는 가장 중요한 요소이다. 콜라젠은 인체조직을 이루는 주된 단백질이고, GAGs은 조직의 미세환경을 결정짓는 주요한 요소로 알려져 있다. 본 연구에서는 1형 콜라젠 스폰지를 탈수 열처리 (A군)하고 EDC로 가교결합한 것 (B군)과 CS를 첨가하여 EDC로 가교결합한 군 (C군)의 스폰지 형태의 콜라젠 지지체을 제조하였다. 제작된 콜라젠 스폰지를 3 mm의 디스크 형태로 토끼 각막의 실질부위에 주머니형태로 이식하였다. 8주 동안 각막의 신생혈관 생성, 혼탁, 지지체의 투명도 정도를 확인하고, 2주, 4주, 8주 후에 적출하여 염증과 각막 섬유모세포의 이동을 확인하였다. 모든 군에서 염증, 신생혈관 생성, 혼탁은 일어나지 않았다. 그러나 CS가 첨가된 콜라젠 스폰지에 섬유모세포의 이동이 많았고, 이식물의 투명도가 증가하였다. 1형 콜라젠 스폰지는 각막 간질에의 생체적합성이 뛰어나 각막 간질로의 대체 가능성이 크고, CS가 첨가된 1형 콜라젠 스폰지는 조직공학적 생인공각막의 재구성에 큰 도움을 줄 것으로 기대된다.

• Journal of Periodontal and Implant Science
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• 제45권4호
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• pp.136-144
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• 2015

Purpose: The objective of this study was to comparatively assess the bone regenerative capacity of absorbable collagen sponge (ACS), biphasic calcium phosphate block (BCP) and collagenated biphasic calcium phosphate (CBCP) loaded with a low dose of recombinant human bone morphogenetic protein-2 (rhBMP-2). Methods: The CBCP was characterized by X-ray diffraction and scanning electron microscopy. In rabbit calvaria, four circular 8-mm-diameter defects were created and assigned to one of four groups: (1) blood-filled group (control), (2) rhBMP-2-soaked absorbable collagen sponge (0.05 mg/mL, 0.1 mL; CS group), (3) rhBMP-2-loaded BCP (BCP group), or (4) rhBMP-2-loaded CBCP (CBCP group). The animals were sacrificed either 2 weeks or 8 weeks postoperatively. Histological and histomorphometric analyses were performed. Results: The CBCP showed web-like collagen fibrils on and between particles. Greater dimensional stability was observed in the BCP and CBCP groups than in the control and the CS groups at 2 and 8 weeks. The new bone formation was significantly greater in the BCP and CBCP groups than in the control and CS groups at 2 weeks, but did not significantly differ among the four groups at 8 week. The CBCP group exhibited more new bone formation in the intergranular space and in the center of the defect compared to the BCP group at 2 weeks, but a similar histologic appearance was observed in both groups at 8 weeks. Conclusions: The dose of rhBMP-2 in the present study enhanced bone regeneration in the early healing period when loaded on BCP and CBCP in rabbit calvarial defects.

• 대한치주과학회:학술대회논문집
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• 대한치주과학회 2004년도 제44회 종합학술대회 연제초록
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• pp.53-53
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• 2004

• Journal of Periodontal and Implant Science
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• 제29권3호
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• pp.447-472
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• 1999

The preclinical and clinical studies reviewed herein show that rhBMP-2 induces normal physiologic bone in relevant defects in the craniofacial skeleton. The newly formed bone assumes characteristics of the adjacent resident bone, and allows placement and osseointegration of dental implants. Clearly, the bone inducing capacity of rhBMP-2 is carrier and site dependent. rhBMP-2 in an absorbable collagen sponge carrier induces relevant bone formation in space providing defects. Space providing carries extends this possibility to non-space providing sites. Notably, some ceramic and polymeric biomaterials may substantially interfere with rhBMP-2 induced osteogenesis.

• Archives of Plastic Surgery
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• 제33권4호
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• pp.413-422
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• 2006

Purpose: This study was designed to compare the wound healing effect of silk fibroin, alginate and fibroin/ alginate blend sponge with clinically used Nu gauze in a rat skin defect model. Methods: Two full thickness excisions were made on the back of Sprague-Dawley rat. The excised wound was covered with either of the silk fibroin(SF), alginate (SA), or fibroin/alginate blend sponge(SF/SA). On the postoperative days of 3, 7, 10 and 14, the wound area was calculated by image analysis software. At the same time, a skin wound tissue was biopsied. Results: Healing time 50% ($HT_{50}$) of SF/SA sponge treated group was dramatically reduced as compared with that of control treatment. We also found that the $HT_{50}$ of SF/SA sponge was significantly decreased as compared with either those of SF or SA treatment. Furthermore, SF/SA treatment significantly increased the size of epithelialization and collagen deposition as well as the number of PCNA positive cells on epidermal basement membrane as comapred with those of control treatment. Conclusion: Our results suggest that the wound healing effect of SF/SA blend sponge is the best among other treatments including SF and SA during the whole wound healing period.

• Journal of Periodontal and Implant Science
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• 제45권6호
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• pp.238-246
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• 2015

Purpose: The purpose of this study was to evaluate bone formation around recombinant human bone morphogenetic protein (rhBMP-2)-coated implants placed with or without absorbable collagen sponge (ACS) in rabbit maxillary sinuses. Methods: The Schneiderian membrane was elevated and an implant was placed in 24 sinuses in 12 rabbits. The space created beneath the elevated membrane was filled with either blood (n=6) or ACS (n=6). In the rabbits in which this space was filled with blood, rhBMP-2-coated and non-coated implants were alternately placed on different sides. The resulting groups were referred to as the BC and BN groups, respectively. The AC and AN groups were produced in ACS-grafted rabbits in the same manner. Radiographic and histomorphometric analyses were performed after eight weeks of healing. Results: In micro-computed tomography analysis, the total augmented volume and new bone volume were significantly greater in the ACS-grafted sinuses than in the blood-filled sinuses (P<0.05). The histometric analysis showed that the areas of new bone and bone-to-implant contact were significantly larger in the AC group than in the AN group (P<0.05). In contrast, none of the parameters differed significantly between the BC and BN groups. Conclusions: The results of this pilot study indicate that the insertion of ACS after elevating the Schneiderian membrane, simultaneously with implant placement, can significantly increase the volume of the augmentation. However, in the present study, the rhBMP-2 coating exhibited limited effectiveness in enhancing the quantity and quality of regenerated bone.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권4호
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• pp.221-230
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• 2012

Objectives: This study sought to evaluate the efficacy of collagen graft materials, as compared to other graft materials, for use in healing calvarial defects in rabbits. Materials and Methods: Ten mm diameter calvarial defects were made in ten rabbits. The rabbits were then divided into 4 groups: control, autogenous bone graft, SureOss graft, and Teruplug graft. Bone regeneration was evaluated using histological and radiographic methods. Results: Based on visual examination, no distinct healing profile was observed. At 4 weeks after treatment, histological analysis showed there was no bone regeneration in the control group; however, at 8 weeks after treatment, new bone formation was observed around the margin of the defective sites. In the autogenous bone graft group, new bone formation was observed at 4 weeks after treatment and mature bone was detected around the grafted bone after 8 weeks. In the SureOss graft group, at 4 weeks after treatment, acute inflammatory and multinuclear cells were noted around the grafted materials; at 8 weeks after treatment, a decrease in graft materials coupled with new bone formation were observed at the defective sites. In the Teruplug graft group, new bone formation was detected surrounding the bone margin and without signs of inflammation. There were statistically significant differences observed between the graft and control group in terms of bone density as evidenced by radiographic analysis using computed tomography (P<0.05), particularly for the autogenous bone graft group (P<0.001). Conclusion: These results suggested that autogenous bone, SureOss and Teruplug have the ability to induce bone regeneration as compared to an untreated control group. The osteogenic potential of Teruplug was observed to be lower than that of autogenous bone, but similar to that of SureOss.

• Journal of Periodontal and Implant Science
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• 제37권4호
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• pp.859-869
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• 2007

Naked DNA and standard vectors have been previously used for gene delivery. Among these, PEI can efficiently condense DNA and has high intrinsic endosomal activities. The aim of this study is to investigate whether the cationic polycation PEI could increase the transfection efficiency of BMP expressing DNA using a vector-loaded collagen sponge model. BMP-2/pcDNA3.1 plasmid was constructed by subcloning human BMP-2 cDNA into the pcDNA3.1 plasmid vector. PEI/DNA complexes were prepared by mixing PEI and BMP-2/pcDNA3.1 and the constructed complexes were loaded into the collagen sponges. In vitro studies, BMSCs were transfected with the PEI/BMP-2/pcDNA3.1 complexes from collgen sponge. The level of secreted BMP-2 and alkaline phosphatase activities of transfected BMSCs were significantly higher in PEI/BMP-2/pcDNA3.1 group than in BMP-2/pcDNA3.1 group (p<0.05). Transfected BMSCs were cultured and mineralization was observed only in cells treated with PEI/BMP-2/pcDNA3.1 complexes. In vivo studies, PEI/BMP-2/pcDNA3.1/collagen, BMP-2/pcDNA3.1/collagen and blank collagen were grafted in skeletal muscle of nude mice. Ectopic bone formation was shown in PEI/BMP-2/pcDNA3.1/collagen grafted mouse 4 weeks postimplantation, while not in BMP-2/pcDNA3.1 grafted tissue. This study suggests that PEI-condensed DNA encoding for BMP-2 is capable of inducing bone formation in ectopic site and might increase the transfection rate of BMP-2/pcDNA3.1. As a non-viral vector, PEI offers the potential in gene therapy for bone engineering.

• Toxicological Research
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• 제16권1호
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• pp.17-25
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• 2000

Chitosan cross-linked collagen-glycosaminoglyan (CCGM) is an artificial skin substitute made to form a sponge like dimensional matrix. It can be used to facilitate reconstruction of dermal tissue when applied on large wounds such as severe burns. In order to study the toxicological effects of CCGM the cytotoxicity, local irritation and skin sensitization test were carried out according to the standards of ISO 10993. In the cytotoxicity test utilizing LDH and MTT test, both the CCGM and its extract had no toxicity of Balb/c 3T3 cells. The local irritatioin test on rabbit skin demonstrated that CCGM did not promote any harmful when directly applied on skin. In addition, it did not elicit any allergic reaction in the guinea pig maximization test. Based on these results, it is suggested that CCGM is a material without cytotoxicity, local irritation and allergenicity.

• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1577-1582
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• 2006

Cartilage tissue engineering has emerged as an alternative approach for reconstruction or repair of injured cartilage tissues. In this study, rabbit chondrocytes were cultured in a three-dimensional environment to fabricate a new cartilaginous tissue with the application of tissue engineering strategies based on biodegradable PLGA microspheres. Chondrocytes were seeded on PLGA microspheres and cultured on a rocking platform for 5 weeks. The PLGA microspheres provided more surface area to adhere chondrocytes compared with PLGA sponge scaffolds. The novel system facilitated uniform distribution of the cells on the whole of the PLGA microspheres, thus forming a new cartilaginous construct at 4 weeks of culture. The histological and immunohistochemical analyses verified that the number of chondrocytes and the amount of extracellular matrix components such as proteoglycans and type II collagen were significantly greater on the PLGA microspheres constructs as compared with those on the PLGA sponge scaffolds. Therefore, PLGA microspheres enhanced the function of chondrocytes compared with PLGA sponge scaffolds, and thus might be useful for formation of cartilage tissue in vitro.