• Journal of Korean Dental Science
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• 제5권2호
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• pp.77-87
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• 2012

Purpose: This study examined the scanning electron microscopic feature, protein marker expression and osteoinductive activity of demineralized dentin matrix (DDM) from human for nude mice. Materials and Methods: Twenty healthy nude mice, weighing about 20 g were used for study. DDM from Human was prepared and implanted into the dorsal portion of nude mouse. Before implantation, DDM was examined by scanning electron microscopy (SEM). Nude mice were sacrificed at 2 weeks, 4 weeks and 8 weeks after DDM grafting and evaluated histologically by H-E, MT staining. And also immunohistochemistry analysis (ostecalcin, osteopontin) was performed. Result: Dentinal tubules and collagen fibers were observed by SEM of dentin surface of DDM. The DDM induced bone and cartilage independently in soft tissues. And, the histological findings showed bone forming cells like osteoblasts, fibroblasts at 2, 4 and 8 weeks. On immunohistochemistry analysis, osteocalcin and osteopontin positive bone forming cells were observed. Conclusion: This results showed that the DDM from human has osteoinductive ability and is a good alternative to autogenous bone graft materials.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.7.1-7.5
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• 2016

Background: This study examined the osteoinductive activity of demineralized dentin matrix (DDM) from human and polydeoxyribonucleotide (PDRN) for nude mice. Methods: Twenty healthy nude mice, weighing about 15~20 g, were used for the study. DDM from human and PDRN were prepared and implanted subcutaneously into the dorsal portion of the nude mice. The nude mice were sacrificed at 1, 2, and 4 weeks after grafting and evaluated histologically by hematoxylin-eosin and Masson's trichrome staining. The specimens were also evaluated via a histomorphometric study. Results: The DDM and PDRN induced new bone, osteoblasts, and fibroblasts in soft tissues. The histological findings showed bone-forming cells like osteoblasts and fibroblasts at 1, 2, and 4 weeks. New bone formation was observed in the histomorphometric study. In particular, the ratio of new bone formation was the highest at 2 weeks compared with the first week and fourth week. Conclusions: In this study, we showed that the PDRN used in this experimental model was able to induce bone regeneration when combined to the DDM.

• 한국치위생학회지
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• 제8권1호
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• pp.13-22
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• 2008

This study compared tooth's remineralization using enamel surface artificially demineralized with 0.1M lactate and HCL solution using Vicker's Hardness Number(VHN) to compare CPP-ACP and remineralization of nano-sized Carbonate Apatite's initial caries. Using pH circulation models divided into 0% nano-CA, 5% nano-CA, 10% nano-CA, 10% CPP-ACP and D.W. they were treated for 5 minutes, three times a day for 14 days to get the following results. 1. There were no significant differences among the initial surface hardness of samples demineralized surface of front tooth in 5 groups. and all 5 groups' surface hardness reduced significantly after demineralization of enamel. 2. When inquiring into hardness changes through pH circulation model, the highest hardness change was in 5% nano-CA group. Also. 10% nano-CA and 10% CPP-ACP groups increased significantly. but there was no significant difference statistically. In generalizing the above experiment results, nano-sized Carbonate Apatite showed remineralization, and compared to 10% CPP-ACP group, 5% nano-CA had remineralization to artificial caries. thus implies that when we develop method to contact with tooth of nano-CA in the future, it is expected to gain synergy effect on function of saliva, a natural remineralization material.

• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.163-175
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• 2004

This study was performed to evaluate bone formation in the calvaria of rabbit by the concept of guided bone regeneration with titanium mesh membrane and demineralized freeze-dried bone. The animal was sacrificed at 2 weeks, 4 weeks, 8 weeks, and 12 weeks after the surgery. Non-decalcified specimens were processed for histologic analysis. 1. The titanium mesh but the biocompatibility was excellent the cell-occlusiveness was feeble. 2. The cell-occlusiveness was feeble and also the soft tissue growth of the upper part of the newly-formed bone after operating was excellent in early stage. 3. The maintenance ability of the space for the GBR very was excellent. 4. The titanium mesh the tissue-integration was superior the wound fixation ability excellent. 5. The demineralized freeze-dried bone did not promote the bone regeneration. 6. With the lapse of time, formation quantity of the bone some it increased, it increased quantity very it was feeble. Within the above results, the titanium mesh for the guided bone regeneration was excellent, the dεmineralized freeze-dried bone confirmed does not promote bone regeneration.

• Preventive Nutrition and Food Science
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• 제5권4호
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• pp.225-229
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• 2000

The antioxidative and protective activities of kefir, low-fat dry milk (NFDM) extract and fractions on SFME cells in serum-free medium were investigated. Kefir and low-fat kefir and NFDM extract were made by solubilizing the freeze dried powder forms in deionized water, filtering through glass prefilter, 12 ㎛ and 2 ㎛ membrane, and demineraling with chelating resin. Kefir, low-fat kefir and NFDM extract were fractioned into dialyzate and retentate by dialysis with membrane tube having the molecular cut-off of 3,500 Dalton. An antioxidative activity was analyzed by the in vitro model system using a linoleic acid. In the case of kefir an antioxidative activity was detected only in the retentate of kefir extract. On the other hand NFDM showed an antioxidative activity in extract, demineralized extract, dialyzate and retentate. The retentate of kefir extract had the higher antioxidative activity than that of NFDM extract. Kefir showed the protective effect of SFME cells in serum-free medium in extract, demineralized extract and retentate, but low-fat kefir didn't. NFDM had the similar protective effect on SFME cells as extract, demineralized extract and retentate of kefir.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.27.1-27.7
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• 2015

The aim of this study was to evaluate the clinical relevance of autogenous fresh demineralized tooth (Auto-FDT) prepared at chairside immediately after extraction for socket preservation. Teeth were processed to graft materials in block, chip, or powder types immediately after extraction. Extraction sockets were filled with these materials and dental implants were installed immediately or after a delay. A panoramic radiograph and a conebeam CT were taken. In two cases, tissue samples were taken for histologic examination. Vertical and horizontal maintenance of alveolar sockets showed some variance depending on the Auto-FDT and barrier membrane types used. Radiographs showed good bony healing. Histologic sections showed that it guided good new bone formation and resorption pattern of the Auto-FDT. This case series shows that Auto-FDT prepared at chairside could be a good material for the preservation of extraction sockets. This study will suggest the possibility of recycling autogenous tooth after immediate extraction.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.185-195
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• 1994

This study was conducted to evaluate the healing potential of hydroxyapatite and demineralized freeze dried bone in 5 dogs. Chronic periodontitis was induced by ligating elastic wire randomized as follows. The group in which only flap operation was performed was used as control. The group in which flap operation using nonresorbable nonporous hydroxyapatite (Orthomatrix)was performed was used as experimental I. The group which flap operation using resorbable porous hydroxyapatite (Biocoral) was performed as experimental II. The group in which flap operation using demineralized freeze-dried bone was performed was used as experimental III. Thereafter dogs serially sacrificed at the 1,2,4 and 8 weeks and the specimens were prepared, and stained with Hematoxilin-Eosin stain for the light microscopic evaluation. The results of the this study were as follows : 1. Control group : progressive inflammatory cell infiltration till 4 weeks and epithelial undergrowth. 2. Group I. : epithelial undergrowth and new bone formed with fibrous margin around HA granule. 3. Group II. : no epithelial undergrowth and direct bone formation at the porous granule 4. Group III. : could not see epithelial undergrowth but obviously new cementum formation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제15권1호
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• pp.63-79
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• 1993

To repair bony defects with tansplanted bone in the body, fresh autogenous bone is undoubtly, the most effective bone graft for clinical applications. But the demineralized bone has the matrix-induced bone formation which was suggested by Urist in 1965. Many authors assisted that demineralized bone powder induces phenotypic conversion of mesenchymal cells into osteoblasts, with high-density bone formation. The process of inducing differentiated cells becomes osteogenic properties. The purpose of this study was to evaluate the osteoinductive capacity of allogenic freeze-dried demineralized bone block (FDD, $7{\times}7mm$) and to compare FDD with the same sue of deep-frozen allogenic bone(DF), fresh autogenous bone (A) after implantation. The histological and ultrastructural features of tissue responses were examined after 1, 2, 4, 6, 8 weeks implantation of each experimental groups in the operative site of the New Zealand white rabbits. The results were as follows : 1. Inflammatory cell infiltration generally has appeared at 1 week, but reduced at 4 weeks in each group, but most severe in DF group. 2. Osteoblastic activity has increased for 4 weeks, but decreased at 6 weeks in each group and there was no significant difference among experimental groups. 3. New bone formation has begun at 1week, least activations in A groups, and showed the revesal line of bone formation among each group at 6 to 8 weeks. 4. Bone resorption has appeared at 1 week, but disappeared at 4 weeks in both A and DF groups, but more severe in DF than A groups. 5. In ultrastructural changs, the DF group have showed the most remarkable osteoclastic activities among experimental groups. 6. Osteoid or tangled collagen fibrils near the implanted sites were replaced by more mature, lamellated bony trabeculae during bone remodeling. There was little difference among each experimental groups. 7. During the convertion osteoblasts to osteocytes which embedded within the bone matrix, there was organ-less-poor cytoplasm, increased nuclear chromatin, abundant rough endothelial reticulum (RER) in each groups. From the above the findings, the DF group shored more bone resorption and foreign body reaction than FDD and A groups, and FDD group showed more new bone formation or osteoblastic activity than DF and A groups in early stage. There was no significant difference of cellular activities among the FDD DF, and A groups according to the time.

• 대한치과교정학회지
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• 제35권1호
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• pp.43-50
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• 2005

본 연구는 교정용 브라켓 부착 시 사용되는 접착제 중 two paste type의 실런트 레진 적용이 법랑질 탈회에 미치는 영향을 알아보고자 시행되었다. 건전한 표면을 가진 발치된 소의 상악절치 48개를 실험재료로 하여 법랑질 처리 방법에 따라 4개 군으로 분류하고 각 군을 Phase II (Reliance, Itasca III)를 이용하여 치면처리 하였다. 대조군으로서 아무런 처리를 하지 않은 Group 1.37% 인산으로 30초간 산부식을 시행한 Group 2, 산부식 후 실런트 A와 B를 동량으로 혼합하여 도포한 Group 3과 산부식 후 실런트를 도포하고 레진 페이스트 A와 B를 동량으로 혼합하여 도포한 Group 4로 분류하여 각 군을 인공탈회용액에서 탈회시킨 다음 공초점 레이저 주사현미경을 이용하여 각각의 탈회된 깊이를 측정한 후 비교한 결과, 탈회된 법랑질의 평균 깊이는 $47.4{\mu}m$ (Group 1). $61.8{\mu}m$ (Group 2). $13.9{\mu}M$(Group 3) $8.2{\mu}n$ (Group 4) 로 나타났다. 산부식 후 인공탈회용액에 노출되는 군 (Group 2) 은 산부식 없이 노출도는 군 (Group 1) 센 비해 탈회된 깊이가 더 깊은 것으로 나타났으며 (p<0.05) 실런트 레진을 도포한 군 (Group 3: 은 산부식 없이 노출되는 군 (Group 1)이나 산부식 후 노출되는 군 (Group 2) 에 비해 탈회된 법랑질 깊이가 유의성 있게 감소하였다. (p<0.05). 접착레진으로 부착된 군 (Group 4)은 법랑질 탈회가 거의 나타나지 않았다. 이상의 연구결과는 교정치료 시 법랑질 탈회 가능성을 줄이기 위해서 브라켓 부착 시 실런트 레진의 도포가 유용함을 시사하였다.

• 한국임상수의학회지
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• 제27권6호
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• pp.652-662
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• 2010

개에서 넙다리뼈 뼈겉질에 결손을 유발하여 뼈 이식재로 사용하는 calcium sulfate (CS), demineralized bone matrix (DBM), calcium metaphosphate (CMP)를 이식하여 뼈 재생 효과를 비교 분석하였다. 비글견 9두, 총 18개의 넙다리뼈에 각각 4개의 결손부를 외과적으로 유발하고, 이 중 3 곳에는 CS, DBM, CMP를 각각 이식하고 나머지 하나는 대조군으로서 총 4개의 군으로 나누어 관찰하였다. 방사선 검사는 수술 전, 수술 후 4, 8, 24주에 실시하였으며, 조직 검사는 4, 8, 24주에 안락사 후에 실시하였다. 방사선 검사에서는 시간 경과에 따른 이식재의 분해성을 관찰할 수 있었으며 뼈겉질의 치유가 이루어짐을 확인하였다. CS군은 빠르게 흡수되어 뼈겉질을 형성하였으며, DBM군은 이식재 주위에 뼈가 형성되면서 점차적으로 겉질뼈를 채우는 양상을 보였다. CMP군은 빠르게 흡수되지 않고 24주가 지난 후에도 이식재 잔여물이 남아 뼈 겉질의 구조적 역할을 수행하면서 뼈를 형성하였다. 방사선 intensity는 대조군이 모든 실험군에 비해서 유의성 있게 낮았다 (p < 0.05). 조직학적 검사에서 CS,DBM,CMP 모두 대조군과 비교할 때 뼈 재생을 촉진시켰으며 (p < 0.05), 뼈 겉질 결손 시 입자 공간이 다소 넓은 DBM보다 CMP가, CMP보다 CS가 뼈 접합체로 적합하였다. CS, DBM, CMP 모두 상당 양의 뼈를 형성하여, 뼈 재생 촉진에 효과적인 것으로 판단되었다.