• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.101-105
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• 2009

The purpose of this study is to reduce autogenous shrinkage of high-strength concrete. Previous studies were investigated to measure the effects of reductions to autogenous shrinkage when applying bean oil to concrete. The results of the study showed that as the mixture rate of BO increased, fluidity decreased and air quantity decreased slightly. In early age, compressed strength increased compared to Plain while decreased in long-term age. As an autogenous shrinkage characteristic, reduction effect increased according to increase in mixture rate. When mixture rate is 1%, approximately 30% decreased compared to Plain in BO. At 2%, BO decreased by about 32%. In addition, in the case of BO, autogenous shrinkage was shown to decrease compared to expansive additive and shrinkage-reducing agent.

• 대한토목학회논문집
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• 제26권5A호
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• pp.909-915
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• 2006

콘크리트의 자기수축을 예측하기 위해 기존 수화도와 자기수축의 진행 속도 차이를 불포화공극 생성 속도로 가정하고 시멘트 페이스트의 자기수축 실험을 통하여 물-결합재비에 반비례하는 불포화공극 보정계수를 산정할 수 있었다. 이를 자기수축 기여 성분과 미기여 성분이 고려된 변형 Pickket 모델을 이용하여 콘크리트의 자기수축을 예측하였으며, 실험값 및 기존 Tazawa 모델과 일치하는 경향을 나타내어 불포화공극 보정계수에 의한 자기수축 예측이 타당함을 알 수 있었다. 그러나 강도의 함수로 설정된 기존 CEB-FIP 자기수축 예측 모델의 경우 최종 자기수축률과 자기수축 발현 시간함수에 대하여 다소의 수정이 필요할 것으로 판단된다.

• Journal of Chest Surgery
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• 제44권1호
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• pp.25-31
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• 2011

Background: Mature autogenous arteriovenous fistulas have better long term patency and require fewer secondary interventions compared to arteriovenous prosthetic graft. Our Study evaluated vascular patency rates and incidence of interventions in autogenous arteriovenous fistulas and grafts. Material and Methods: A total of 166 vascular access operations were performed in 153 patients between December 2002 and November 2009. Thirty seven caeses were excluded due to primary access failure and loss of follow-up. One group of 92 autogenous arterioveous fistulas and the other group of 37 arteriovenous prosthetic grafts were evaluated retrospectively. Primary and secondary patency rates were estimated using the Kaplan-Meier method. Results: The primary patency rate (84%, 67%, 51% vs. 51%, 22%, 9% at 1, 3, 5 year; p=0.0000) and secondary patency rate (96%, 88%, 68% vs. 88%, 65%, 16% at 1, 3, 5 year; p=0.0009) were better in autogenous fistula group than prosthetic graft group. Interventions to maintain secondary patency were required in 23% of the autogenous fistula group (average 0.06 procedures/patient/year) and 65% of prosthetic graft group (average 0.21 procedures/patient/year). So the autogenous fistula group had fewer intervention rate than prosthetic graft group (p=0.01) The risk factor of primary patency was diabetus combined with ischemic heart disease and the secondary patency's risk factor was age. Conclusion: Autogenous arteriovenous fistulas showed better performance compared to prosthetic grafts in terms of primary & secondary patency and incidence of interventions.

• International Journal of Oral Biology
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• 제42권4호
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• pp.203-211
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• 2017

The aim of this study was to evaluate the role of demineralized and particulate autogenous tooth, and interleukin-6 in bone regeneration. A demineralized and particulate autogenous tooth was prepared and human osteoblast-like cells (MG63) and human osteosarcoma cells were inoculated into the culture. The rate of cell adhesion, proliferation and mineralization were examined, and the appearance of cellular attachment was observed. An 8 mm critical size defect was created in the cranium of rabbits. Nine rabbits were divided into three groups including: An experimental group A (3 rabbits), in which a demineralised and particulate autogenous tooth was grafted; an experimental group B (3 rabbits), in which a demineralized, particulate autogenous tooth was grafted in addition to interleukin-6 (20 ng/mL); and a control group. The rabbits were sacrificed at 1, 2, 4 and 6 weeks for histopathological examination with H-E and Masson's Trichrome, and immunohistochemistry with osteocalcin. The cell-based assay showed a higher rate of cell adhesion, mineralization and cellular attachment in the experimental group A compared with the control group. The animal study revealed an increased number of osteoclasts, newly formed and mature bones in the experimental group A compared with the control group. Eventually, a higher number of osteoclasts were observed in the experimental group B. However, the emergence of newly formed and mature bone was lower than in the experimental group A. The current results suggest that treatment with demineralized and particulate autogenous tooth and interleukin-6 is not effective in stimulating bone regeneration during the bone grafting procedure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.150-151
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• 2021

This study aims to achieve an enhancement in the quality of high strength concrete through a reduction in autogenous shrinkage by supplying the moisture needed for hydration through recycled aggregates that retain high amounts of moisture. The result showed that, moisture supply increased with the higher replacement rate, autogenous shrinkage dropped by up to 45 percent.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.180-181
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• 2017

This study aims to analyze the high strength mortar's fundamental properties and autogenous shrinkage properties by taking into consideration the result of the previous study in which it was found that ERBO(Biodiesel) exercises greatest effect on the expansion effect of mortar, and changing the time and rate of mixing the ERBO. A total of five levels were set as experimental variables: the three levels of the rate of ERBO, 0, 0.5, 1.0%, and the two levels of the time of mixing the ERBO: first, adding the ERBO with the mixing water and mixing it before, and second, mixing it after the mortar is completely mixed. It was found that the rate of length change decreased as the rate of ERBO increased, and the rate of length change was lower when the ERBO was mixed sooner.

• Journal of Periodontal and Implant Science
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• 제38권4호
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• pp.669-678
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• 2008

Purpose: The purpose of this study was to evaluate 2 years cumulative survival rate of implants on augmented sinus area using MBCP, mixture of MBCP and ICB, and mixture of MBCP and autogenous bone by means of clinical and radiologic methods. Materials and Methods: In a total of 37 patients, 41 maxillary sinuses were augmented and 89 implant fixtures were installed simultaneously or after a regular healing period. The patients were divided in 3 groups: MBCP only, MBCP combined with ICB, MBCP combined with autogenous bone. After delivery of prosthesis, along 2 years of observation period, all implants were evaluated clinically and radiologically. And the results were as follows. Results: The results of this study were as follows. 1. A 2 year cumulative survival rate of implants placed with sinus augmentation procedure using MBCP was 97.75%. 2. Survival rate of implants using MBCP only was 97.62%, MBCP and ICB was 100%, MBCP and autogenous bone was 95%. There was no statistically significant difference between 3 groups. 3. Only 2 of 89 implants were lost before delivery of prosthesis, so it can be regarded as an early failure. And both were successfully restored by wider implants. Conclusion: It can be suggested that MBCP may have predictable result when used as a grafting material of sinus floor augmentation whether combined with other graft(ICB, autogenous bone) or not. And the diameter, length, location of implants did not have a significant effect on 2 year cumulative survival rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권6호
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• pp.274-282
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• 2013

Objectives: The posterior maxillary region often provides a limited bone volume for dental implants. Maxillary sinus elevation via inserting a bone graft through a window opened in the lateral sinus wall has become the most common surgical procedure for increasing the alveolar bone height in place of dental implants in the posterior maxillary region. The purpose of this article is to assess the change of bone volume and the clinical effects of dental implant placement in sites with maxillary sinus floor elevation and autogenous bone graft through the lateral window approach. Materials and Methods: In this article, the analysis data were collected from 64 dental implants that were placed in 24 patients with 29 lacks of the bone volume posterior maxillary region from June 2004 to April 2011, at the Department of Oral and Maxillofacial Surgery, Inha University Hospital. Panoramic views were taken before the surgery, after the surgery, 6 months after the surgery, and at the time of the final follow-up. The influence of the factors on the grafted bone material resorption rate was evaluated according to the patient characteristics (age and gender), graft material, implant installation stage, implant size, implant placement region, local infection, surgical complication, and residual alveolar bone height. Results: The bone graft resorption rate of male patients at the final follow-up was significantly higher than the rate of female patients. The single autogenous bone-grafted site was significantly more resorbed than the autogenous bone combined with the Bio-Oss grafted site. The implant installation stage and residual alveolar height showed a significant correlation with the resorption rate of maxillary sinus bone graft material. The success rate and survival rate of the implant were 92.2% and 100%, respectively. Conclusion: Maxillary sinus elevation procedure with autogenous bone graft or autogenous bone in combination with Bio-Oss is a predictable treatment method for implant rehabilitation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권4호
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• pp.337-343
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• 2010

Purpose: By reviewing literature on the subject, we compared the survival rate of implants placed in various graft materials used for maxillary sinus augmentation. Materials and Methods: The search protocol used the Pubmed electronic database, with a time limit from 1998 to 2009. Keywords such as 'sinus lift,' 'sinus augmentation,' 'sinus floor elevation,' 'sinus graft,' 'bone graft,' 'implants,' 'oral implants,' and 'dental implants' were used, alone and in combination, to search the database. We selected articles and divided them into three groups by type of graft materials: Group 1. Autogenous bone group: autogenous bone alone; Group 2. Combined bone group: autogenous bone in combination with bone substitutes; and Group 3. Substitute group: bone substitutes alone or bone substitute combinations. Results: We selected 37 articles concerning a total of 2,257 patients and 7,282 implants; 417 implants failed. The total implant survival rate (ISR, %) was 94.3%. In Group 1, 761 patients and 2,644 implants were studied; 179 implants failed and the ISR was 93.2%. In Group 2, 583 patients and 1,931 implants were studied; 126 implants failed and the ISR was 93.5%. In Group 3, 823 patients and 2,707 implants were studied; 112 implants failed and the ISR was 95.9%. Conclusion: Implants inserted in grafts composed of bone substitutes alone or in grafts composed of autogenous bone in combination with bone substitutes may achieve survival rates better than those for implants using autogenous bone alone (P<0.05).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권4호
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• pp.156-160
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• 2013

Objectives: Interest in bone graft material has increased with regard to restoration in cases of bone defect around the implant. Autogenous tooth bone graft material was developed and commercialized in 2008. In this study, we evaluated the results of vertical and horizontal ridge augmentation with autogenous tooth bone graft material. Materials and Methods: This study targeted patients who had vertical or horizontal ridge augmentation using AutoBT from March 2009 to April 2010. We evaluated the age and gender of the subject patients, implant stability, adjunctive surgery, additional bone graft material and barrier membrane, post-operative complication, implant survival rate, and crestal bone loss. Results: We performed vertical and horizontal ridge augmentation using powder- or block-type autogenous tooth bone graft material, and implant placement was performed on nine patients (male: 7, female: 2). The average age of patients was $49.88{\pm}12.98$ years, and the post-operative follow-up period was $35{\pm}5.31$ months. Post-operative complications included wound dehiscence (one case), hematoma (one case), and implant osseointegration failure (one case; survival rate: 96%); however, there were no complications related to bone graft material, such as infection. Average marginal bone loss after one-year loading was $0.12{\pm}0.19$ mm. Therefore, excellent clinical results can be said to have been obtained. Conclusion: Excellent clinical results can be said to have been obtained with vertical and horizontal ridge augmentation using autogenous tooth bone graft material.