• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.779-793
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• 2000

The ultimate goal of periodontal disease therapy is to promote the regeneration of lost periodontal tissue, there has been many attempts to develop a method to achieve this goal, but none of them was completely successful. This study was designed to compare the effects of treatment using resorbable barrier membrane($Biomesh^{?}$) in combination with autogenous bone graft material with control treated by only modified Widman flap. 22 infrabony defecs from 10 patients with chronic periodontitis were used for this study, 10 sites of them were treated with resorbable barrier membrane and autogenous bone graft material as experimental group and 12 site were treated by only modified Widman flap as control group. Clinical parameters including probing depth, gingival recession, bone probing depth and loss of attachment were recorded at 6-8 months later, and the significance of the changes was statistically analyzed. The results are as follows : 1. Probing depth of the two group was reduced with statistically significance(P<0.05), but this changes were not different between the two experiment, control group with statistically significance. 2. Gingival recession showed statistically significant increase in control group(P<0.05), but not in experimental group, and initial values of the two group were in statistically significant difference(P<0.05). 3. Bone probing depth showed statistically significant decrease in experimental group(P<0.05), but not in control group, and this changes were different between the two experiment, control group with statistically significance(P<0.05). 4. Loss of attachment showed statistically significant decrease in experimental group(P<0.05), but not in control group, and this changes were different between the two experiment, control group with statistically significance(P<0.05) On the basis of these results, treatment using resorbable barrier membrane in combination with autogenous bone graft material improve the probing depth, bone probing depth and loss of attachment in infrabony defects.

• Journal of Periodontal and Implant Science
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• 제38권3호
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• pp.453-466
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• 2008

Purpose: The purpose of this research is to study about initial adhesion, proliferation and activation of osteoblast to titanium surface treated with machined, hydroxyapatite coating, resorbable blast material blasting and anodizing method. Material and Methods: After treating the titanium surface of each block with machined, impurities were removed and sterilized. The number of cells attached from cultured osteoblast of respective experimental groups were measured at 1, 4, 7, and 14day and alkaline phosphatase, calcium, and inorganic phosphate concentration of cultured solution was measured. Result: Anodizing group showed the highest rate of cell attachment and proliferation activity. RBM treated group showed the highest increasing on their alkaline phosphatase activity, on the calcium apposition, on inorganic phosphate apposition of 1 and 4 days in cultured osteoblast to compare with other groups. Conclusion: On the basis of these findings, we conclude that surface modification of titanium was profoundly effected on the attachment, proliferation and activation of osteoblast in initial stage osseointegration.

• 한국콘텐츠학회논문지
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• 제9권10호
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• pp.474-481
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• 2009

본 연구는 보육기관에 다니는 유아와 어머니를 대상으로 성인애착 유형과 유아의사소통 유형간의 관계를 알아보고, 이를 통해 가족 내에서 이루어지는 언어의 중요성을 인식하고 부모교육의 제반 정보를 제공하고 유아의 의사소통 능력을 향상시킬 수 있는 기초 자료를 제공하는데 연구의 목적이 있다. 이러한 목적을 토대로 어머니의 성인애착 유형과 유아의 의사소통유형 과의 관계를 규명하기 위해 다음과 같은 연구문제를 설정 하였다. 1. 어머니의 성인애착유형과 유아의 의사소통능력은 어떠한 관계가 있는가? 2. 어머니의 성인애착유형이 유아의 의사소통능력에 어떠한 영향을 미치는가? 연구대상은 대전광역시 어린이집에 다니고 있는 만3-5세 유아와 그들의 어머니들이다. 이들에게 성인애착측정도구와 유아 의사소통유형 도구를 사용하였다. 연구결과 성인애착유형과 유아의 의사소통유형과는 상관관계가 나타나지는 않았으나 하위요인별 분석에서는 의존성과 부정적 의사소통유형, 불안성과 긍정적 의사소통유형은 정적상관관계가 있는 것으로 나타났다. 상관관계분석을 토대로 중다회귀분석한 결과 어머니의 성인애착 유형중 불안성이 유아의 의사소통 능력을 예측할 수 있는 주요변인임을 알 수 있었다.

• 디지털융복합연구
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• 제17권11호
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• pp.289-295
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• 2019

본 연구는 패드가 부착된 장갑의 유용성에 대해 파악함으로써 효과적인 심폐소생술을 제시하고자 연구를 시행하였다. 연구대상 및 자료수집은 G광역시에 위치해 있는 G대학교의 심폐소생술 강의를 이수한 응급구조과 대학생 50명을 대상으로 2019년 4월 1일부터 2019년 4월 30일까지 시행하였으며, SPSS /WIN 23.0 Program을 이용하여 분석하였다. 연구결과, 패드부착장갑 착용 전보다 착용 후가 가슴압박총점수, 가슴압박수, 가슴이완율, 손위치정확도, 압박속도 영역에서 심폐소생술 질이 더 높게 나타남에 따라 패드부착장갑의 착용이 기존의 맨 손 심폐소생술보다 가슴압박질을 더 향상시키는 것으로 파악할 수 있었다. 이는 향후 심폐소생술 교육의 기초자료로 활용 및 실무 중심 프로그램을 마련에 기여할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1547-1554
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• 2015

The potential of microalgae biofuel has not been realized because of the low productivity and high costs associated with the current cultivation systems. In this study, a new low-cost and transparent attachment material was tested for cultivation of a filamentous algal strain, Stigeoclonium sp., isolated from wastewater. Initially, the different materials tested for Stigeoclonium cultivation in untreated wastewater were nylon mesh, polyethylene mesh, polypropylene bundle (PB), polycarbonate plate, and viscose rayon. Among the materials tested, PB led to a firm attachment, high biomass (53.22 g/m², dry cell weight), and total lipid yield (5.8 g/m²) with no perceivable change in FAME profile. The Stigeoclonium-dominated biofilm consisted of bacteria and extracellular polysaccharide, which helped in biofilm formation and for effective wastewater treatment (viz., removal efficiency of total nitrogen and total phosphorus corresponded to ~38% and ~90%, respectively). PB also demonstrated high yields under multilayered cultivation in a single reactor treating wastewater. Hence, this system has several advantages over traditional suspended and attached systems, with possibility of increasing areal productivity three times using Stigeoclonium sp. Therefore, multilayered attached growth algal cultivation systems seem to be the future cultivation model for large-scale biodiesel production and wastewater treatment.

• The Journal of Advanced Prosthodontics
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• 제1권1호
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• pp.56-61
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• 2009

STATEMENT OF PROBLEM. The success of titanium implants is due to osseointegration or the direct contact of the implant surface and bone without a fibrous connective tissue interface. PURPOSE. The purpose of this study was to evaluate the osteoblast precursor response to titanium-10 tantalum-10 niobium(Ti-Ta-Nb) alloy and its sputtered coating. MATERIAL AND METHODS. Ti-Ta-Nb coatings were sputtered onto the Ti-Ta-Nb disks. Ti6-Al-4V alloy disks were used as controls. An osteoblast precursor cell line, were used to evaluate the cell responses to the 3 groups. Cell attachment was measured using coulter counter and the cell morphology during attachment period was observed using fluorescent microscopy. Cell culture was performed at 4, 8, 12 and 16 days. RESULTS. The sputtered Ti-Ta-Nb coatings consisted of dense nanoscale grains in the range of 30 to 100 nm with alpha-Ti crystal structure. The Ti-Ta-Nb disks and its sputtered nanoscale coatings exhibited greater hydrophilicity and rougher surfaces compared to the Ti-6Al-4V disks. The sputtered nanoscale Ti-Ta-Nb coatings exhibited significantly greater cell attachment compared to Ti-6Al-4V and Ti-Ta-Nb disks. Nanoscale Ti-Ta-Nb coatings exhibited significantly greater ALP specific activity and total protein production compared to the other 2 groups CONCLUSIONS. It was concluded that nanoscale Ti-Ta-Nb coatings enhance cell adhesion. In addition, Ti-Ta-Nb alloy and its nanoscale coatings enhanced osteoblast differentiation, but did not support osteoblast precursor proliferation compared to Ti-6Al-4V. These results indicate that the new developed Ti-Ta-Nb alloy and its nanoscale Ti-Ta-Nb coatings may be useful as an implant material.

• 대한치과보철학회지
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• 제40권5호
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• pp.470-483
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• 2002

The purpose of this study was to investigate further the mechanics of failure of magnets used for denture retention. Dyna magnets were retrived from denture that had failed after 34 months of clinical use. The magnets were observed and sectioned in order to analyse with high resolution scanning electron microscope. From this study, corrosion behaviors of used magnetic attachment were analysed. The results were as follows ; 1. In Nd-Fe-B based magnetic materials, the erosion-corrosion was started at ununiformed part of stainless steel cover. 2. Corrosion was initiated at weared stainless steel surface and then magnetic materials were spalled by corrosive solution. 3. Spatting was occurred in Nd-Fe-B magnet materials due to corrosion products and then corrosion rate was increased drastically. 4. Corrosion started from ununiformed stainless steel surface as well as welded zone. In conclusion, the failure of magnets may occur by either breakdown of the welding or breakdown of the encapsulating material. So, it is considered that the corrosion problem of dental magnetic materials could be solved to some extent with surface treatment of dental magnetic materials.

• Journal of Periodontal and Implant Science
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• 제38권3호
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• pp.551-556
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• 2008

Purpose: Cemental tear is an uncommon form of root fracture that can lead to rapid localized attachment loss. When it is exposed in the periodontal pocket, it should be removed to prevent accumulation of dental plaque and calculus. Material and Methods: 2 patients were diagnosed as a cemental tear and they were treated with conventional flap operation and subgingival curettage. Additional treatments such as bone graft or guided tissue regeneration were not performed. Result: Symptoms subsided after the treatment. Periodontal pocket has been reduced but no gain of clinical attachment was observed. Remnant of cemental fragment remained after curettage. However, periodontal pocket was stably maintained and there was no recurrence. Conclusion: Periodontal attachment loss associated with cemental tear can be successfully treated with conventional periodontal surgical and nonsurgical procedures.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.13-23
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• 2002

The ultimate goal of periodontal therapy is directed to arresting the progression of the disease, and regenerating the fibrous attachment. In order to achieve such treatment aim, the plaque and calculus must be eliminated and the physiological conditions of the root surface must be changed to facilitate the attachment and migration of the new fibroblasts, The method of changing the proper root surface conditions to promote the healing of periodontal tissue involves mechanical procedures, such as scaling and root planing, and chemical procedures such as tetracycline-HCl. However, the formation of a long junctional epithelium was most frequently observed type of healing. Thus, the aim of this study was to examine in vitro the influence of surface conditioning of dentin by TC-HCl on human gingival epithelial cell attachment. Human gingival epithelial cells were obtained from healthy retromolar pad area(under the age 23 years). Seventy two teeth extracted from severe periodontitis were used as study material. To evaluate the epithelial cell attachment to dentin, the prepared specimen was divided to four groups. For the control group, only scaling and root planing were carried out, and for the test group, 1 to 3, the concentration of the TC-HCl was 50, 125 and 250mg/ml respectively. After cell cultivation time of 1-, 3-. 24 hour, for the indirect quantitative assessment of gingival epithelial cell attached to dentin sample, the absorbance of epithelial cell unattached to dentin was measured. The results were as follows; 1. There was no statistically significant difference between scaling and root planing group and TC-HCl 50mg/ml 125mg/ml and 250mg/ml group about absorbance of unattached epithelial cell to dentin sample(p>0.5). 2. As time passes, the absorbance of unattached gingival epithelial cell to dentin sample was decreased statistically significant(p<0.05). 3. There was no statistically significant difference among the TC-HCl group(p>0.05) We concluded that there was similar effect on gingival epithelial cell attachment between TC-HCl conditioning on root surface and only scaling and root planing treatment

• The Journal of Advanced Prosthodontics
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• 제7권4호
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• pp.323-328
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• 2015

PURPOSE. This in-vitro study was designed to evaluate retention forces, microleakage and plastic deformation of a prefabricated 2-implant bar attachment system (SFI-Bar, Cendres+$M{\acute{e}}taux$, Switzerland). MATERIALS AND METHODS. Two SFI implant-adapters were torqued with 35 Ncm into two implant analogues. Before the tube bars were finally sealed, the inner cavity of the tube bar was filled with liquid red dye to evaluate microleakage. As tube bar sealing agents three different materials were used (AGC Cem (AGC, resin based), Cervitec Plus (CP; varnish) and Gapseal (GS; silicone based). Four groups with eight specimens each were tested (GS, GS+AGC, AGC, CP). For cyclic loading, the attachment system was assembled parallel to the female counterparts in a chewing simulator. The mean retention forces of the initial and final ten cycles were statistically evaluated (ANOVA, ${\alpha}{\leq}.05$). RESULTS. All groups showed a significant loss of retention forces. Their means differed between 30-39 N initially and 22-28 N after 50,000 loading cycles. No significant statistical differences could be found between the groups at the beginning (P=.224), at the end (P=.257) or between the loss of retention forces (P=.288). Microleakage occurred initially only in some groups but after 10,000 loading cycles all groups exhibited microleakage. CONCLUSION. Long-term retention forces of the SFI-Bar remained above 20 N which can be considered clinically sufficient. The sealing agents in this study are not suitable to prevent microleakage.