치아 마모 환자에서 수직고경 증가를 동반하여 단일구조 지르코니아 보철물로 완전구강회복을 시행한 증례

오경철,정문규,김지환,심준성 大韓齒科補綴學會 2012 대한치과보철학회지 Vol.50 No.3

과도한 치아 마모는 교합면에 손상을 야기하고, 치수 병변, 교합 부조화, 기능장애, 심미적 문제 등을 야기할 수 있다. 과도한 치아 마모를 갖고 있는 환자들을 치료하고자 할 때 수직교합고경(vertical dimension of occlusion, VDO)의 상실 여부와 수복을 위한 악간 공간의 적절성 여부에 기반하여 분류를 할 필요가 있다. 본 증례의 환자는 다수 치아들의 마모를 지닌 50세의 남성으로, 과도한 치아 마모가 있지만 수직교합고경의 상실은 없으며 수복을 위한 악간 공간이 부족하였다. 이러한 경우 수직교합고경을 증가시켜 치료를 진행하는 것을 고려할 수 있다. 수직교합고경의 증가를 필요한 범위 내에서 최소로 줄이고, 증가된 수직교합고경 상에서 안정화 기간을 거친 뒤 안정된 교합 접촉을 제공할 수 있다면, 수직고경 증가를 동반한 치료법은 안정성을 가질 수 있다. 본 남성 환자를 치료하기 위해 수직고경의 증가를 동반하여 전치부와 구치부에서 단일 구조 지르코니아를 이용한 고정성 보철물로 수복을 하였다. 일련의 치료과정을 통하여 기능적인 면과 심미적인 면에서 만족스러운 결과를 얻었기에 보고하는 바이다. Excessive occlusal wear results in unacceptable damage to the occluding surfaces, and can cause pulpal injury, occlusal disharmony, impaired function, and aesthetic deformity. Patients with severely worn dentition need to be classified as several categories relative to the vertical dimension of occlusion (VDO) and the interocclusal distance for the prosthetic space. When treating patients classified as those who have excessive wear without loss of occlusal vertical dimension but with limited space, we could consider treating them at an increased vertical dimension of occlusion. Treatments at an increased vertical dimension of occlusion may provide stability, given that the amount of its increase was minimal, and a perfected occlusion was achieved after enough stabilization period. A 50-year-old male visited the department of Prosthodontics in Yonsei University Dental Hospital with the chief complaint of worn teeth on lower anterior area. Reconstruction at an increased vertical dimension of occlusion was planned. After the compatibility of the new vertical dimension of occlusion had been confirmed under interim fixed restorations, definitive fixed restorations composed of full-contour monolithic zirconia prostheses were placed. This case presents that a satisfactory clinical result was achieved by restoring the worn dentition at an increased vertical dimension of occlusion with an improvement in esthetics and function.

Bakers' Yeast와 포도당을 이용한 m-Bromoaniline의 합성

오성환,김경순,박종옥 慶星大學校 1995 論文集 Vol.16 No.2

Rapid and selective reduction of nitro compounds is of importance for the synthesis of amino compounds, particularly when a molecule has other reducible groups. In recent years, Bakers' Yeast has been used for enantioselective reductions of β-keto esters of α,β -unsaturated carbonyl compounds. However, little attention has been paid to the reduction of aromatic nitro compounds by Bakers' Yeast. In this paper, we wish to report a mild and selective reduction of m-bromonitrobenzene with Bakers' Yeast and glucose.

이종접합재 접합 계면근방 균열의 응력 및 파괴특성

오정국,차용훈,오환섭,박준건,박경식 朝鮮大學校 機械技術硏究所 1998 機械技術硏究 Vol.1 No.1

현재까지 이종마찰압접재의 강도측정은 실험 (7)-(15)에 의해 구해져 왔다. 하지만 최근 이종마찰압접재의 효율성을 인정하여 여러 실용 부품에 응용하려는 연구가 한창 진행중이다. 이종마찰압접재에 대한 저자들(1)-(6)의 기초실험결과 일반적인 단종재와는 상이한 파괴거동(3)이 관찰되었고, 파괴역학적인 관점에서 정성적인 data 확보가 필요하게 되었다. 따라서 본 연구에서는 인장시험시 이종마찰압접재의 접합강도와 미소균열들에 의한 파괴거동을 파괴역학적 관점에서 해석적으로 고찰하여 보고자 경계요소법(BEM ; Boundary Element Method)을 이용하여 접합계면을 포함하는 접합부를 중심으로 계면상의 응력분포와 계면의 중앙에 결함이 균열로써 존재하는 경우의 응력분포와 인장시험시 열영향부에서 관찰된 균열의 모델링을 통한 균열선단에서의 응력해석을 행하였고, 그 결과 얻어진 중요한 내용을 요약하면 다음과 같다. 계면의 중앙에 균열이 존재하는 접합계면의 표면부에서 응력의 특이성이 발생하며 탄성계수의 비가 증가할수록 특이성이 증가함이 관찰되었다. 탄성계수의 비가 일정한 경우 균열의 크기가 변화하여도 계면의 표면부에서 발생하는 특이성은 거의 같은 값을 갖게 되며, 탄성계수의 비가 증가할수록 표면부의 응력 특이성의 크기는 증가한다. 이종마찰압접재의 인장시험시 관찰된 균열을 모델링 하여 해석한 결과 최대 응력 기준으로 살펴볼 때 인접한 균열선단에서의 응력분포는 균열을 합체시키는 방향으로 작용함을 알 수 있다. In this study stress distribution on the interface and stress near tip of the sub-interface crack in the dissimilar friction welded material is analyzed by using of BEM( Boundary Element Method). Stress singularity near surface of model to analyze is observed for various crack length and ratio of elastic modulus. Tensile and shear stress distribution near two neithbor sub-interface crack tips are analyzed. Existance of singularity near surface on the interface is particular situation so that we need to investigate for dissimilar friction welded materials by means of numerical analysis method.

正陽湖 沿岸生態系의 基礎生産

吳炅煥,成敏雄 慶尙大學校 기초과학연구소 1987 基礎科學硏究所報 Vol.3 No.-

慶南 陜川郡 大陽面 所在 正陽湖에서 水生管束植物의 生活刑에 따른 基礎生産을 測定하고 湖沼 전체의 年純生産을 調査하여 다음과 같은 結果를 얻었다. 1. 挺水植物인 줄(Zizania latifolia)의 順基礎生産性은 生體植物量 增加 690g m^-2, 枯死體量 增加 297g m^-2 및 枯死體分解量 58g m^-2를 합친 1,045g m^-2이었으며, 生長期間 中 太陽에너지 固定效率은 1.68%였다. 2. 浮水植物인 마름(Trapa spp.)은 浮葉叢 直徑이 증가함에 따라 水面위의 密度가 감소되었고, 順基礎生産性은 生體植物量 增加 322g m^-2와 枯死體量 增加 208g m^-2를 합친 530 m^-2이었으며, 生長期間中 太陽에너지 固定效率은 0.78%였다. 3. 沈水植物의 順基礎生産性은 14g m^-2이고 太陽에너지 固定效率이 0.02%로서 세 生活形中 가장 낮았다. 4. 각 生活型別 分布面積과 順基礎生産量으로부터 正陽湖 전체의 年間純生産量을 계산하면 줄이 404.9ton으로 전체 生産量의 70.2%를 차지하였고, 마름 167.3ton(29.0%) 및 沈水植物 4.4ton(0.8%)이었다. 따라서 正陽湖 전체에서 水生管束植物의 年純生産量은 576.6ton이었다. Primary productivity and annual net production of the three life forms of the aquatic vascular plants were studied in the littoral zone lake Jungyang, Hapchun-gun, Gyeongsangnam-do, Korea from April to October in 1986. Net primary productivity of Zizania latifolia was 1,045 gm-2 including living biomass, dead standing crop, and disappearance. And net conversion efficiency of PhAR(photosynthetically ative radiation) of Z. latifolia was 1.68% during the growing season. Rosette density of Trapa spp. was decreased with the increase of rosette diameter. Net primary productivity of Trapa spp. was 530 gm-2 and the net conversion efficiency of PhAR was 0.78% during the growing season. Net primary productivity of the submersed plants was 14 gm-2 and the net conversion efficiency of PhAR was 0.02%. It was estimated that total annual net primary production of the aquatic vascular plants in lake Jungyang was 576.6 ton, which was composed of 404. ton(70.2%) of Z. latifolia, 167.3 ton(29.0%) of Trapa spp., and 4.4 ton(0.8%) of submersed plants.

正陽湖 水生高等植物의 基礎生産

吳炅煥 慶尙大學校 1985 論文集 Vol.24 No.2

湖水生態系에 대한 硏究의 일환으로 慶南 陝川都 大洋面 所在 正陽湖에서 1982년 5월부터 9월까지 水生高 等植物들의 基礎生産과 몇 가지 物理化學的 環境要素들을 調査하여 다음과 같은 結果를 얻었다. 1. 調査對象地域인 正陽湖는 水深이 平均 70cm로서 비교적 얕으며, 水溫·pH·酸化還元電位差·溶存酸素量 둥이 水深에 따른 差異와 함께 季節的으로도 變化가 있었는데, 특히 5월부터 8월까지가 다른 時期에 비해 水深別 差異가 많았다. 2. 開放水面에 優古種으로 나타나는 마름은 水面위의 포기直徑이 증가함에 따라 單位面積當 포기數와 個體數가 감소되었으며, 葉面積比는 8월까지 증가하다가 그후 감소되었다. 3. 마름이 生長함에 따라 部位別 生物量比率도 변화 하는데 잎과 뿌리의 生物量이 차지하는 比率이 특히 높아서 7월에는 85%에 달하였다. 4. 마름의 葉面積이 증가함에 따라 沈水植物안 물수 세마, 붕어마름, 새우가래, 말즘, 애기가래, 검정말둥의 現存量은 감소되는 傾向을 나타내었다 Seasonal changes in the biomass of aquatic macrophytes, and in some physico-chemical characteristics of water quality were investigated at the littoral zone of Lake Jungyang, Hapchun-gun, Gyeongsangnam-do, Korea from May to September in 1982. The mean value of water depth was about 70cm, and vertical stratification for the water quality was formed from May to August. The density of rosette and individual of Trapa japonica, the dominant species on the water surface, was decreased as the diameter of the rosette increased. Percentage of biomass for the each organ was changed according to the growth, and that for the leaf and root was highest in July as 85%. The biomass of the submersed aquatic macrophytes such as Myriophyllum vertlcillatum, Ceratophyllum demersum, Potamogeton maackianus, P. crispus, P. octandrus, and Hydrilla vertcillata was negatively correlated with the leaf area of T. japonica.

수생관속식물이 호소생태계의 부영양화에 미치는 영향

오경환 慶尙大學校 기초과학연구소 1990 基礎科學硏究所報 Vol.6 No.-

Physico-chemical environments, community structure, actual vegetation map, distribution area, annual net production, and annual uptake amount of nitrogen and phosphorus by the aquatic vascular plants were investigated in the typical valley blocked lakes such as Jungyang Lake, Woopo, and Yongsan Reservoir and their adjacencies. The flora of the aquatic vascular plants was composed of 26 emergent plants, 13 submersed plants, 11 free floating plants, and 4 floating leaved plants or 54 taxa. Annual net production of the emergent plants, the floating leaved and free floating plants, the submersed plants was 53.1-64.8%, 24.7-44.4%, and 2.5-8.5% out of the total production. The amounts of nitrogen and phosphorus absorbed by them were 38.7-51.3 and 48.9-63.0%, 37.3-58.1 and 29.2-48.7%, and 3.2-12.2 and 2.4-8.7% out of the total uptake amounts.

정양호 연안대의 수생 유관속식물상과 군집구조

오경환,김철수 慶尙大學校 기초과학연구소 1986 基礎科學硏究所報 Vol.2 No.-

호수생태계의 식생구조에 대한 연구의 일환으로 경남 합천군 대양면에 소재한 정양호의 연안대에서 1986년 4월부터 9월까지 수생유관속 식물군집을 조사하여 다음과 같은 결과를 얻었다. 1. 조사대상 지역에서 조사된 수생유관속식물은 43과 79속 90종 16변종 1품종으로서 총 107종류였으며, 생활형별로는 정수식물이 79.4%, 침수식물 9.3%, 부수식물 7.5%, 부엽식물 3.7% 등으로 정수식물이 가장 많았다. 2. chi-square test에 의한 종간상관분석 결과 34종의 식물이 5% 또는 1% 수준에서 양이나 음의 상관을 나타내었으며 사마귀풀, 세모고랭이, 물옥잠, 수염마름 등이 양의 상관빈도가 높았고 유전마름과 말즘은 음의 상관빈도가 높았다. 3. 조사지역의 식생은 개구리밥, 생이가래, 자라풀, 유전마름, 네마름, 검정말, 말즘, 새우가래, 이삭물수세미, 붕어마름 등 10종으로 구성된 개방수면 지역의 식물군과 사마귀풀, 세모고랭이, 물옥잠 등을 포함하여 23종으로 구성된 습지 식물군으로 구별되었다. Flora and vegetation structure for the aquatic vascular plants were investigated in the littoral zone of Lake Jungyang, Gyeongsangnam-do, Korea from April to September, 1986. The flora was composed of 43 families, 79 genera, 90 species, 16 varieties, and 1 forma or 107 taxa. Among them, 79.4% were emergent plants, 9.3% submersed plants, 7.5% free-floating plants, and 3.7% floating-leaved plants, respectively. It was shown that 34 species of the aquatic vascular plants were positively or negatively correlated each other at 5% or 1% level from the results of association analysis by chi-square test. The vegetation in the area could be classified into two groups: the open-water vegetation composed of 10 species such as Spirodela polyrhiza, Salvinia natans, Hydrocharis dubia, Trapa natans, Trapa bicornis, Hydrilla verticillata, Potamogeton crispus, Potamogeton maackianus, Myriophyllum spicatum, Ceratophyllum demersum, and the marsh vegetation of 23 species including Potamogeton distinctus, Sagittaria trifolia, S. aginashi, Alopecurus aequalis var. amurensis, Polypogon fugax, Beckmannia syzigachne, Zizania latifolia, Eleocharis dulcis, E. mamillata var. cyclocarpa, Scirpus triqueter, Cyperus iria, Aneilema keisak, Monochoria korsakowi, Persicaria thunbergii, P. hastato-sagittata, P. hydropiper, Ranunculus cantoniensis, Ludwigia prostrata, Myriophyllum ussuriense, Oenanthe javanica, Nymphoides peltata, Trapella sinensis var. antennifera, and Lobelia chinensis.

15番 空間群의 6가지 다른 表現

吳美蘭,金勁翰,李珍昊,徐日煥 충남대학교 기초과학연구소 1996 忠南科學硏究誌 Vol.23 No.2

The space group number 15 can be expressed in six different ways as C2/c, A2/a, A2/n, C2/n, I2/a, and I2/c according to the setting of unit cell axes. The International Union of Crystallography has chosen C2/c for a standard space group of the space group number 15. In this paper, it has been shown that the six space groups are mutually transformed.

抗精神病藥物에 依한 無顆粒細胞症 治驗 1例

吳東財,申榮宇,張煥一,趙京杉,朴康圭 大韓神經精神醫學會 1985 신경정신의학 Vol.24 No.1

The authors experienced a female schizophrenic patient who revealed severely decreased leucocytes (350/㎣) with the manifestation of high fever, chillness and sore throat after the oral administration of neuroleptics. Agranulocytosis induced with the use of neuroleptic drugs has been well known complication in psychiatric practice although it is quite rare. In this case, following the combined use of neuroleptics (thioridazine halopondol and chlorproonazine), severe decrement of leucocytes (mainly lymphocytes with few neutrophils) was noticed on peripheral blood and marked decrement of erythroid series, especially of myeloid series, with decrement of total cellular elements were confirmed through the biopsy of bone marrow. She did not responded at all to the massive administration of antibiotics, but dramatic improvement was noticed both clinically and in the follow-up biopsy findings of bone marrow after two times trial of leukapheresis.

자동차용 브레이크 마찰재에서의 환원분철의 마찰특성에 관한 연구

정진오,이경환,김옥삼,김봉수 순천대학교 2000 순천대학교 자연과학논문집 Vol.19 No.1

In most automotive brakes, the friction material is used to convert the kinetic energy into heat. The friction material is a complex composite consisting of a resin, reinforcing fibers, lubricants and filler materials. In an attempt to enhance the friction performance of the friction material, a trial was done to examine the substitution of filler material by the reduction iron powder. In this study, two types of reduction powder M1 and M3 was prepared by the reduction process developed by Hanta M&B Inc. M1 and M3 which has reduction ratio of 1.5 and 92% respectively was used in place of BaSO_4, which was conventionally used as a filler material. The amount of M1 and M3 was varied as 10, 20, 30%, while the other component remains the same except the replaced BaSO_4. For those specimens with different amount of reduction iron powder, friction performance tests such as friction coefficient, rotor compatibility were conducted by using brake dynamometer. The bonding strength and hardness tend to decrease with use of M1 and M3, but specific weight decreased with increase of M1 and M3. The friction coefficient increased with use of M1 up to 10%, but decreased for use of M1 more than 20%. However the use of M3 resulted in a decrease of friction coefficient all the way. The surface roughness decreased with the use of M1 and M3, except for a case of excessive use of M1 of 30%. The rotor surface roughness did not show any correspondence with hardness of friction material in this study.