자가 산부식 프라이머의 적용시간이 상아질의 미세인장 결합강도에 미치는 영향

조영곤,이영곤,김종욱,박병철,김종진,최희영,진철희,유상훈 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5

This study evaluated the influence of application time of self-etching primers on microtensile bond strength (μTBS) to dentin using three self-etching primer adhesive systems. Dentin surfaces were exposed from forty-eight human molars. They were conditioned with three self-etching primers (Clearfil SE Bond [SE], Unifil Bond [UF], Tyrian SPE + One Step Plus [TY]) and different primining times (10s, 20s, 30s and 40s). Composite resins were bonded to dentin surfaces and specimens were made. μTBS was tested and statistically compared using by one-way ANOVA and Tukey's Test. The results of this study presented that priming time for 10s in SE and UF groups and for 30s and 40s in TY group was highly decreased μTBS to dentin.

단일 단계 접착제의 변연 미세누출

조영곤,정진호,기영재,최희영,진철희,유상훈,김종욱,박병철 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.2

This study evaluated the marginal microleakage of five single step adhesives. Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on both buccal and lingual surfaces of extracted human molar teeth. Prepared teeth were randomly divided into five groups and restored using one of the single step adhesives and composite resins: Prompt L-Pop/Filtek Z-250 (Group 1), AQ Bond/Metafil CX (Group 2), One-Up Bond F/Palfique Toughwell (Group 3), Futurabond/Admira (Group 4), Xeno III/Spectrum TPH (Group 5). The restored teeth were thermocycled. Microleakage was assessed by dye penetration using 2% methylene blue dye solution. The teeth were bisected buccolingually and evaluated for microleakage under steromicroscope. The data were statistically analysed by Kruskal-Wallis test and Mann-Whitney tests. The results of this study were as follows; 1. Microleakage of enamel margins in group 3 was statistically higher than that in groups 1, 2, 4, 5 (p < 0.05) 2. Microleakage of dentin margins in group 1 was statistically higher than that in groups 2, 5, and that in group 3 was statistically higher than that in groups 2, 4, 5 (p < 0.05). 3. Dentin marginal microleakage was higher than enamel marginal microleakage in all experimental groups. In conclusion, Prompt L-Pop showed the least leakage at enamel margin, and AQ Bond showed at dentin margin in this study. Marginal miroleakage in dentin was higher than that in enamel.

상아질에 적용된 재 습윤제가 미세인장 결합강도에 미치는 영향

강희영,조영곤,김종욱,박병철,유상훈,진철희,최희영,기영재 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.2

This study investigated that the effect of rewetting agent on dentinal microtensile bond strength (μTBS). Human molars were sectioned to expose the superficial dentin surfaces. Samples were divided into two groups according to type of adhesives-Single Bond (S) and One-Step (0)], and again subdivided into five groups by different dentin surface treatment-dry for 15s (D) , blot dry (BD) or dry for 15s, and rewet with different rewetting agents[distil1ed water (DW), Gluma Desensitizer (GD) and Aqua-Prep (AP)]for 30s. After application of adhesive, composite resin was built up on the bonding surface. Each tooth was sectioned to obtain stick with 1mm^(2) cross sectional area and the μTBS was determined by EZ test. In the S group, the mean μTBS of GD, AP and BD group was significantly higher than that of DW and D group (p < 0.05). In the 0 group, the mean μTBS of AP, GD, BD and DW group was significantly higher than that of D group (p < 0.05). The data suggested that Gluma Desensitizer and Aqua-Prep could be successfully used as rewetting agents, and Distilled water could be acceptable in aceton based adhesive system only.

복합레진의 지연충전이 미세인장 결합강도에 미치는 영향

박현식,조영곤,박병철,김종욱,최희영,김종진,진철희,유상훈,기영재 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.3

The purpose of this study was to evaluate the effect of immediate or delayed composite resin filling on dentinal microtensile bond strength (μTBS) after applied the adhesive. The coronal dentin of human third molars was exposed. Single-Bond or One-Step was applied on the dentin surfaces, and composite resin were constructed immediately (group 1) or 5 min., 10 min., 15 min., 20 min. and 30 min. (groups 2-6) after an adhesive was applied. The specimens were sectioned and made bar-shaped. Each surface area of them was about l ㎟. The RBS test was performed by EZ test. The results were analysed by One-way ANOVA and Tukey's test at 95 % significance level. The results suggested that the μTBS of Single-Bond to dentin was decreased when the composite resin was constructed 20 min. and 30 min. after Single-Bond was applied. But the μTBS of One-Step was not affected by delayed composite resin filling.

법랑질 접착에 대한 습윤 효과

고근호,조영곤,진철희,유상훈,김종욱,박병철,기영재,최희영,김종진 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.3

This study evaluated the microleakage and interfacial gap between enamel and composite resin under the dry and wet condition of the enamel surface, V shaped class 5 cavities were prepared on the occlusal portion of extracted human molars. Samples were divided into three groups: D group (air dry for 10-15s), BD group (blot dry with moist cotton pellet), and DR group (air dry for 10-15s and rewet with Aqua-Prep F for 20s). Cavities were filled using Aelitefil composite resin after applied One-Step. Microleakage was tested by 2% methylene blue dye solution and the data were statistically analysed by Kruskal-Wallis test and Mann-Whitney test. Also Enamel-resin interface was observed under SEM. Group BD showed statistically lower microleakage than group D (p〈0.05). but there was no statistically significant difference between group BD and DR (p)0.05). At the enamel-resin interface, group D showed the gap of 2 ㎛ thickness, but group BD and DR showed close adaptation. In conclusion, the use of blot dry and rewetting agent (Aqua-Prep F) resulted in decreased microleakage and improved adhesion between enamel and resin when using One-Step.

고진공내의 데칸용매하에서 요오드화 iso-프로필이 니트로벤젠 및 톨루엔과의 착물형성에 관한 연구

김영철,김세경,임종완,구덕자 漢陽大學校 環境科學硏究所 1991 環境科學論文集 Vol.12 No.-

고진공내의 데칸용매하에서의 요오드화 iso-프로필의 용해도를 8, 15, 25℃에서 니트로벤젠과 톨루엔이 존재할 때와 존재하지 않을 때의 두 경우에 대하여 각각 측정하였다. 데칸용매내에 니트로벤젠과 톨루엔이 존재할 때 요오드화 iso-프로필의 용해도가 존재하지 않을 때 보다 더 크고, 톨루엔과 요오드화 iso-프로필과의 상호작용이 니트로벤젠과의 상호작용보다 더 강하게 작용한다는 것을 알 수 있었다. 그리고 니트로벤젠과 톨루엔이 데칸용매내에 존재할 때 요오드화 iso-프로필과 니트로벤젠 및 톨루엔이 각각 불안정한 Complex를 형성한다고 생각되어 이 Complex를 여러 경우의 비율로 가정하여 계산해 본 결과 1 : 1 Comples를 형성한다고 보는 경우의 평형상수 K값이 비교적 일정한 값을 나타내었다. 그러므로 1 : 1 Complex 즉 ??과 ??이 용매속에 형성됨을 알았다. 또한 이 Complex의 생성에 대한 엔탈피, 자유에너지 및 엔트로피의 변화도 산출하였다. The solubilities of iso-propyliodide in decane on high vacuum were measured at 8℃, 15℃ and 25℃ in the presence and absence of nitrobenzene and toluene. When nitrobenzene and toluene exist in system respectively, the solubilities of iso-propyliodide in the presence of nitrobenzene and toluene are greater than in the absence, and the interaction of iso-propyl iodide with toluene is stronger than with nitrobenzene. In the presence of nitrobenzene and toluene, it could be thought that iso-propyl iodide forms unstable complex with nitrobenzene and toluene. The complex was assumed in various ways and it was evaluated that the equilibrium constant K value was relatively constant under the assumption of 1 : 1 complex. Thus, 1 : 1 complexes, ??과 and ?? are formed in the solution. Also, the changes of enthalpy, free energy and entropy for the formation of the complex were calculated.

치아회분과 석고혼합제재 매식과 자가골 동시 이식후 치유과정에 관한 실험적 연구

김영균,김흥중,이상호,여환호,임성철,설인택,정재헌 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

The purpose of this study was to evaluate the efficacy of adding autogenous bone to the toothash-plaster mixture in the healing process of bone. Full-thickness round osseous defects with the diameter of 20mm were made at the calvarial bone of adult dogs (n=19) bilaterally, which were thought to be critical size defect. The right defects were repaired with the toothash-plaster mixture plus autogenous bone (compressed volume 0.3cc) and the left defects with only toothash-plaster mixture. At 2-, 4-, 8-, 12- and 20- week after implantation, dogs were sacrificed and evaluated the osseous healing of bony defects clinically, radiographically, and microscopically. The results were as follows : 1. At the clinical observation, the wound healed very well without any problem except severe swelling in the early period after operation. Slight depression was recognized at the both sides when the portions of cranial defect were palpated. 2. There were statistically significant differences between toothash-plaster mixture groups and autogenous bone added groups at the same period, and among the groups in the bone density of the digital radiograms (P<0.001).There was a tendency that bone density was increasing with time. 3. In light microscopic examination, new bone formation was more active in the autogenous bone added groups than toothash-plaster mixture groups at the early period after mplantation but there is little difference at 20-week after implantation. 4. In fluorescent microscopic examination, the fluorescent band could be observed at the area of active bone formation and the band was more distinct in the autogenous bone added groups then toothash-plaster mixture groups. 5. In transmitted electron microscopic examination, organelles such as rER, Golgi complex and secretory granule and osteoblast were observed. In summary higher volume ratio of autogenous bone is needed to improve the bone healing in that there is little difference between toothash-plaster mixture group and autogenous bone added group at the 20-week after implantation in spite of new bone formation was more active in the autogenous bone added groups than toothash-plaster mixture groups at the early period after operation.

퍼지 제어기 소속함수의 추정을 위한 진화프로그래밍 이용에 관한 연구

김승철,장종승,강신출,임영도 東亞大學校 附設 情報通信硏究所 1996 情報通信硏究所論文誌 Vol.4 No.1

On this paper, the design of fuzzy adaptive controller using an evolution programming combining fuzzy controller to be very effectove in the optimization problem will be proposed. On a proposing control structure, the optimization takes uncertain plants optimized membership function using EP, and we want to take an adaptive controller in the plant as well be adapted control structure to initiate approximate membership function in fuzzy. We show that proposed controller have a good performance than general fuzzy controller through a computer simulation and the real-time control of DC serve motor.

寶城江댐 流域의 植生

金順熙,鄭泳喆,金琮鴻 순천대학교 기초과학연구소 1993 基礎科學硏究誌 Vol.4 No.-

The vegetation, which is based on vascular plants, in the vicinity of the Po^sung-gang dam was investigated phytosociologically over 13 times on 57 points from November, 1991 to July, 1993. Species composition, live form, and community structure of the flora, species diversity, and similarity index were determined, and the profile diagram of plant community and actual vegetation map were constructed. Vascular plant flora in the surveyed area was 34 orders, 92 families, 247 genera, 340 species, 1 subspecies, 44 varieties and 2 forma, in total 387 kinds. The composition of life form was classified into Ch-D_1-R_5-e type. Vegetation was classified into coniferous forest and deciduous broad-leaved forest. Coniferous forests were composed of the communities of Pinus densiflora and P. thunbergii as the natural forest, and P. rigida community, Chamaecyparis obtusa community and other 15 mixed forest communities as artificial forest. Deciduous broad-leaved forests were extensively composed of natural forest such as Quercus acutissima community and Q. aliena community, and artificial forest such as Alnus japonica community, C. crenata community and Robinia pseudo-acacia community, and other 6 mixed forest communities. The communities of Camellia japonica and Miscanthus sinensis var. purpurascens were observed on a small scale in the surveyed area. Species diversity index was 1.105, in coniferous forest and 1.118 in deciduous broad-leaved forest. Similarity index between the two communities was 0.555, which means those communities are remarkably different from each other in species composition. Pterophyta quantity(Pte-Q), which is 0.68, was lower than that of national average, 1.68, while urbanization index measured as 2.37 was higher than that of national average, 9.9. The vegetation of vascular plants in Po^sung-gang Dam was coincided with that of the southern area of the Korearn peninsula, in distribution types of family or genus. It was to be noted that a natural community of Scirpus radicans which is generally believed to be distributed in northern area was found in this surveyed area.

이소퀴놀린과 브롬화벤질류의 반응속도론

김영철 漢陽大學校 自然科學硏究所 2000 自然科學論文集 Vol.19 No.-

아세토니트릴 용매 내에서 파라치환된 브롬화벤질류 (p-CH₃, p-H, p-NO₂)와 이소퀴놀린의 반응을 conductivty 측정법으로 온도 (20, 25, 30℃)변화에서 측정하여 유사1차, 2차반응속도상수를 얻었다. 이때 반응속도상수는 온도가 증가함에 따라 증가하였으며, 또한 기질의 전자주게치환체 (p-CH₃)가 치환된 경우 증가하였다. 이들 반응속도상수로부터 활성화에너지(Ea) 활성화엔탈피 (ΔH≠), 활성화엔트로피 (ΔS≠), 활성화자유에너지 (ΔG≠) 및 Hammett 반응상수 ρ를 구하였다. 이러한 속도론적 연구로 부터 전반적인 반응 메카니즘은 dissociative SN2반응으로 진행됨을 알 수 있었다. The reaction rates of p-substitutied benzylbromides(p-CH₃, p-H, p-NO₂) with isoquinoline have been measured by conductivity method in acetonitrile, and pseudo-first order and second order rate constants are determined at 20, 25 and 30℃. The rate constants are incleased with a function of temperatures and are further incleased by introdusing the electron donating substituents in substrates. The activation energies(Ea), activation parameters(ΔH≠, ΔS≠, ΔG≠) and Hammett ρvalues are calculated from the rate constants. The result of kinetic studies according to the variation of substituent showed that this reation proceeded to dissociative SN2 mechanism.