두부 사측방 촬영술에 의한 건조하악골의 과두영상고찰

조경수,정현대 전남대학교 치과대학 1992 전남치대논문집 Vol.4 No.1

Transcranial radiography has the benefit of providing low equipment cost, and it does not require additional space. The diagnosis of the internal derangement can be made on the basis of the measurement of the joint space by using transcranial radiograph. Thus transcranial radiography is one of the most commonly used radiographic techniques of the diagnosis of TMJ disorders. It is generally known that the transcranial radiograph delineates the lateral third of the condyle. This article intends to help reader understand the morphology of the condylar bony structures through the transcranial radiography. Four radiopaque wire were placed on the condyla surface at intervals of two millimeter from the lateral pole. Using 20 dry mandibles and an Accurad-200 healholder (Denar Corp. U.S.A.). The transcranial radiographs were taken. The results were as follows: 1. The wires that are attached at the distance of 2㎜ from the lateral pole delineate the anterior partition of the condylar outline in the standard and corrected transcranial radiographs. 2. The anterosuperior partition of the condylar outline consists mainly of the image of the wires that are attached at the distance of 2.4㎜ from the lateral pole. 3. The posterosuperior partition of the condylar outline consists mainly of the image of the wires that are attached at the distance of 4.6㎜ from the lateral pole. 4. The posterior partition of the condylar outline consists mainly of the image of the wires that are attached at the distance of 6, 8㎜ from the lateral pole.

Al-Mg-Si合金의 時效擧動에 미치는 加工熱處理의 影響

趙顯麒,李基大,朴定國 慶北大學校 1980 論文集 Vol.30 No.-

Effects of Thermo-Mechanical Treatment(TMT) on ageing behaviours in Al-Mg-Si alloy is investigated by means of tensile test, hardness measurements and transmission electron microscopy. The maximum 0.2% proof stress of the TMT materials in final ageing is higher by 10%∼20% than that of the two-step aged materials. The strength of TMT materials also increases more rapidly than that of two-step aged materials. The maximum 0.2% proof stress of the TMT materials with pre-ageing is higher than that of the TMT materials without pre-ageing. The strength of TMT materials increases with rising pre-ageing temperature, and it decreases with rising final-ageing temperature. Consequently, this type of TMT would have some practical significance in improving the mechanical properties of 6061 alloy.

Al-Zn合金의 時效析出에 미치는 直流電流의 영향

趙顯麒,李基大,金敎漢 慶北大學校 1980 論文集 Vol.29 No.-

The effect of direct current on precipitation in Al-Zn alloy is investigated by measurement of electrical resistance as a function of current density up to about 2400A/㎠ at a constant quenching temperature. The changing rate of electrical resistance is observed at 300°, 350°, 400° and 450℃, from which retarding coefficient is attained. It can be concluded that there exists some effects of direct electric current to retard the ageing-precipitation and this retarding effect is related to the sinking of quenched-excess vacancy into grain boundaries by electromigration. In the case of quenching temperature above 350℃, the retarding coefficient of direct electric current is less than that can be expected.

하악골에 발생된 Low grade 골육종:증례보고

조현이,정종철,김호성,최재욱,성대경,서지훈,김성범,이계혁 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

Osteosarcoma is a primary malignant tumor arising most often in the long bone, but rare in jaw bone. Especially osteogenic sarcoma of the mandible is a rare tumor, comprising less than 0.5% of all head and neck tumors. Osteosarcoma occurs cheifly in young persons, and presenting very survival rates. Histopathologically this tumor can be classified three types, osteoblastic, fibroblastic, chondroblastic and classified from low grade to high grade by anaplasia or mitosis of the tumor cells. Sometimes, the exact diagnosis of osteosarcoma is difficult especially in low grade osteosarcoma, even if clinical or radiographical findings suggest to osteosarcoma. So suspcious to malignant bone tumor in clinical or radiological findings, biopsy should be taked from deep portion and multiple area, and sharing the patient history and radiographs with pathologist will assist in the development of the diagnosis. We report a case of low grade osteosarcoma on the mandible initially difficulty in accurate diagnosis. The patient visited our hospital for routine dental treatment but radiographic findings displayed ill-defined radiolucency with osteoid formation on the mandible. Final diagnosis was difficulty in initial biopsy but subsequent biopsy taked from deep portion presented infiltrative growth and mitosis of the tumor cell in some area with small osteoid bone formation, so we could reach final diagnosis as low grade sarcoma. We treated this patient with bloc resection of the mandible and immediate reconstruction with iliac corticocancellous block.

흉배혈관의 근피 천공분지에 기초한 유리피판의 임상적 이용

조규성,김대영,안호범,이삼용,조백현 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.3

The latissimus dorsi muscle or musculocutaneous flap is one of the most useful flaps in reconstructive surgery. This flap has many advantages, such as its reliable anatomy, long pedicle with large caliber vessels, minimal functional deficit of the donor site, and low incidence of donor site complications. However, the bulkiness of the flap has been considered a disadvantage, so various modifications of technique have been devised. The cutaneous portion of the flap can be safely elevated based on the cutaneous perforating branch of the thoracodorsal vessel. From March 1997 to February 1998, 10 patients underwent reconstructive procedures with thoracodorsal perforator-based free flaps. The composition of the flaps varied in accordance with the nature of the defect. The variances in the flaps were as follows; 3 were cutaneous, 6 musculocutaneous, and 1 osteomusculocutaneous including the rib. All flaps survived with good contour. We concluded that this thin and reliable flap was useful for reconstruction of various defects, and that the composition of the flap, such as subcutaneous, muscle and bone, gave it considerable flexibility as needed.

D.C Magnetron sputtering법으로 제조된 GMR 스핀밸브 조성막에서 증착변수들이 증착속도에 미치는 영향

조대현,이찬규,김병수 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

In this study, we have investigated the influence of sputtering conditions(Ar pressure, Input power) on deposition rate of Ni81Fe19, Fe, Co, Cu, Cr86A114, Cr93Ga7 thin films produced by the method of DC magnetron sputtering. In all films, we have observed that the deposition rate increased with input power because of increasing sputter yield, and ion current density. we have found that the deposition rate was decreased with the pressure of Ar gas.

Nd:YAG 레이저 조사와 불화물 도포가 탈회법랑질의 재광화에 미치는 영향

조현,이광희,김대업 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

Normal pulsed Nd:YAG 레이저 조사와 불소화합물이 산성음료수에 의해 탈회된 법랑질의 표면 미세경도에 미치는 재광화 효과를 평가하고자 한다. 법랑질 시편을 제작하여 50ml 플라스틱 시험관 5개에 코카콜라를 채운 후 30개의 소구치를 6개씩 나누어 넣고 탈회시켰다. 법랑질 표면에 6W 출혁하의 50mJ 에너지 밀도, 20Hz의 pulse rate로 레이저를 조사하였다. 레이저가 조사된 법랑질 표면에 각 군별로 여러 형태의 불소화합물을 처리한 후 탈회 전, 후의 미세경도 및 Diagnodent를 측정하였다. 동일한 방법으로 탈회된 법랑질에 레이저를 조사했을 때와 레이저가 조사된 법랑질 표면에 불소화합물을 처치한 후에 미세 경도 및 Diagnodent를 측정하였다. 법랑질 표면을 산성 음료에 탈회 후, 레이저 조사 후, 불소화합물 처치 후의 각각의 시편에 대하여, 주사전자현미경으로 1500배 확대하여 관찰하였다. 1. 산성 탈회된 법랑질 표면의 미세경도(VHN)가 레이저를 조사한 수와 불소 도포 후에 증가하였으나, 레이저 조사 후의 경도와 불소 도포 후의 경도간의 차이는 유의하지 않았다. 2. 초기 경도, 탈회 후 경도, 레이저 조사 후 경도, 불소 도포 후 경도에서 불소군 간의 차이는 모두 유의하지 않았고, 불소 용액 군과 불소 젤 군에서는 레이저 조사 후의 경도와 불소 도포 후의 경도 간에 유의한 차이가 없었으나, 불소 바니쉬군에서는 유의한 차이가 있었다. 3. Diagnodent 측정치의 변화에서 초기 점수, 탈회 후 점수, 레이저 조사 후의 점수와 불소 도포 후의 점수 간에는 유의한 차이가 있었고, 레이저 조사 후 점수와 불소 도포 후의 점수가 불소 도포 군 사이에서는 유의한 차이가 없었다. 4. 산성 음료수에 탈회된 법랑질 표면에의 Nd:YAG 레이저 조사는 재광화에 효과적이며, 불소화합물의 처치는 레이저의 효과를 증가시키는 부가적인 효과를 갖는다. 5. 주사 전자 현미경상에서 Nd:YAG 레이저가 조사된 법랑질 표면은 전체 표면이 법랑소주가 녹아내려 융합된 매끈한 바닥에 균열이 생기고 분화구가 퍼져 있는 양상을 보였으며, 불소 도포 후에는 균열과 분화구 형태는 뚜렷하지 않으며 탈회된 후의 표면에 가까운 양상을 보였다. The purpose of this in vitro study was to investigate the effects of Nd:YAG laser irradiation and fluorides on acid demineralized enamel. The materials were 30 freshly extracted permanent premolars with intact smooth enamel surfaces. They were demineralized with Coca-cola at 37℃ for 12 hours and then irradiated by Nd:YAG laser with 6W power, 50mJ/㎠ energy density, and 20Hz pulse repetition. After laser irradiation, teeth were treated by three kinds of fluorides; (1) 0.05% NaF fluoride solution (2) 1.23% APF gel and (3) 0.1%F fluoride varnish, microhardness(VHN) and Diagnodent scores were measured and the surfaces of each treated specimens were also observed with SEM under 1500 magnification. The results were as follows: 1. In the change of microhardness(VHN), it decreased to 34.68% from the initial micrhardness, increased to 78.37% after laser irradiation and increased to 82.62% after fluoride treatment, there were significant differences except when it was irradiated and treated with fluoride(P<0.05). 2. In the change of Diagnodent scores, it was decreased to 28.08% from the initial scores after demineralization, and then increased to 59.81% after laser irradiation, and increased to 82.17% after fluoride treatment. Scores were different significantly between the scores of initial, demineralization, laser irradiation and fluoride treatment (P<0.05). All the scores were not different significantly between fluoride types. 3. SEM observation showed that the lased enamel surfaces after demineralization were thermally degenerated and showed molten lava-like appearance and crater with cracks and many microholes.

Al-Zn-Mg合金의 加工熱處理에 미치는 遷移元素의 影響

趙顯驥,李基大,金熙都 慶北大學校 1982 論文集 Vol.33 No.-

An investigation for influence of a small additions of transition metals (Mn, Zr, Cr) on the thermomechanical treatment (TMT) in Al-Zn-Mg alloys has been carried out by means of the measurements of tensile strength and micro-vickers hardness. The results obtained from this experiment are summarized as follows; 1) Hardness and strength of Al-Zn-Mg alloys are increased remarkable by a small additions of transition metals (Mn, Zr, Cr) at as-quenched state. 2) Influence of a small additions of transition metals like Mn, Zr and Cr added to Al-Zn-Mg alloys on ageing phenomena was retarding the ageing character. 3) The mechanical properties (hardness and strength) of Al-Zn-Mg alloys which were processed by TMT are increased when the deformation rate is lower than 30%, on the other hand those of Al-Zn-Mg alloys added transition metals were decreased with increasing deformation rate.

Chiral Cu(Ⅱ)착화합물과 촉매로 유도된 Carbenoid반응에 의한 2-phenylcyclopropane-carboxylic acid의 광화학 이성체의 합성

조남숙,신대현,이종철,나도영 충남대학교 1985 忠南科學硏究誌 Vol.12 No.2

(-)-(IR, 2R)-trans-menthyl-2-phenylcyclopropanecarboxylate has been synthesized with aid of chiral Cu(Ⅱ) complex catalyst by the addition reaction of menthyldiazoacetate to the styrene. The yield was 80%, the purity of trans-compound over 90% and optical purity 75%. These results show the possibility of synthesis of (-)-(IR, 2R)-trans-2-phenylcyclopropane-carboxylic acid with high purities of optical activity and geometric specificity.

正祖의 學問觀을 통해 본 韓國學의 패러다임

조대현 경기대학교 부설 민족사상연구소 2006 민족사상연구 Vol.14 No.-