교정용 미니 임플랜트 고정원과 SWA en masse sliding retraction 시 전치부 치축 조절 요인에 관한 유한요소해석

정혜심,성상진,문윤식,조영수,임승민 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.5

교정용 미니 임플랜트 고정원을 이용한 교정 치료가 보편화되며, SWA와 이를 이용한 en masse sliding retraction은 임상에서 흔히 사용하는 치료법이 되었다. 그러나 고정원을 성공적으로 보존하려는 노력에 비해, 발치 공간 폐쇄 시 전치부 치축 조절에 관여하는 요인에 대한 보고는 아직까지 부족한 실정이다. 본 연구에서는 제1소구치를 제거한 상악 치아와 치주 인대 그리고 치조골에 대한 3차원 유한요소 기준모델을 제작하였고, 제1대구치와 제2소구치 사이 주호선 10 mm 상방에 식립된 교정용 미니 임플랜트를 고정원으로 사용할 경우, 측절치-견치 사이의 견인 훅의 높이를 변화시키며 후상방 견인력을 가하거나, 주호선에 보상 만곡을 부여하는 것이 전치부 치축 조절에 어떤 영향을 미치는지 시뮬레이션 하였다. 또한 전치부 치축이 설측 경사된 모델을 같은 실험 조건으로 시뮬레이션 하여 발치 공간 폐쇄 시 설측 경사된 전치부 치축을 유지하거나 개선할 수 있는 요인을 검토하였고, 다음과 같은 연구 결과를 얻었다. 2 mm 높이의 견인 훅에 대하여 후상방으로 견인력을 가할 경우 발생하는 함입력으로 인하여 전치부 설측 경사가 더 감소되지는 않았다. 견인 훅의 높이가 5 mm인 경우 후상방 견인력을 가하면, 측절치의 치관 순측 및 치근 설측 이동이 일어나고, 견치의 비조절성 후방 경사 이동이 심화되었다. 4 mm의 보상 만곡은 측절치의 치관 순측 및 치근 설측 이동을 일으키고, 견치의 비조절성 후방 경사 이동을 감소시켰다. 또한 전치부가 설측 경사된 모델을 기준모델과 같은 실험 조건으로 시뮬레이션 한 경우 치근면의 응력 분포와 25000배 확대된 그래프 상에서의 치아 이동 양상은 매우 유사하였다. 이상의 결과는 미니 임플랜트-SWA sliding 생역학을 구사 시 견인 훅의 위치와 와이어 상의 보상 만곡의 유무에 의해 전치부의 치축 조절이 달라지며 실제 임상에서 가이드라인으로 활용될 수 있을 것이다. Objective: With development of the skeletal anchorage system, orthodontic mini-implant (OMI) assisted en masse sliding retraction has become part of general orthodontic treatment. But compared to the emphasis on successful anchorage preparation, the control of anterior teeth axis has not been emphasized enough. Methods: A 3-D finite element Base model of maxillary dental arch and a Lingual tipping model with lingually inclined anterior teeth were constructed. To evaluate factors influencing the axis of anterior teeth when OMI was used as anchorage, models were simulated with 2 mm or 5 mm retraction hooks and/or by the addition of 4 mm of compensating curve (CC) on the main archwire. The stress distribution on the roots and a 25000 times enlarged axis graph were evaluated. Results: Intrusive component of retraction force directed postero-superiorly from the 2 mm height hook did not reduce the lingual tipping of anterior teeth. When hook height was increased to 5 mm, lateral incisor showed crown-labial and root-lingual torque and uncontrolled tipping of the canine was increased. 4 mm of CC added to the main archwire also induced crown-labial and root-lingual torque of the lateral incisor but uncontrolled tipping of the canine was decreased. Lingual tipping model showed very similar results compared with the Base model. Conclusion: The results of this study showed that height of the hook and compensating curve on the main archwire can influence the axis of anterior teeth. These data can be used as guidelines for clinical application.

직업교육의 이론적 위상에 대한 재고찰 : 개념과 방법론을 중심으로

조정윤 한국산업교육학회 2001 산업교육연구 Vol.8 No.-

지식기반사회는 지식이 생산력의 원천이 되는 사회로서 직업교육에 크게 두 가지의 함의를 제공한다. 하나는 여기서의 '지식'은 기존의 지식과는 다른 실천적·암묵적 지식인데, 이것은 작업 환경에서 지식이 만들어지고 공유되는 과정에 주목할 필요를 제기한다. 또 하나는 직업교육의 관점과 방법론에 대한 근본적인 혁신이 없이는 지식기반사회가 실현되기 어렵다는 것이다. 그러나 직업교육은 질 낮은 교육이며 단순기능의 반복이라는 인식이 이러한 혁신을 가로막고 있다. 이에 따라 본 연구에서는 직업교육에 대한 기존의 관점을 비판적으로 극복할 수 있는 방안을 모색하는 동시에, 직업교육의 방법론을 재정립하고자 하였다. In the knowledge-based society, not only does vocational education take on a new meaning, but its methodology will also make significant contributions to methodology in education overall. Discrepancies still exist, however, in that most vocational education scholars and society in general view vocational education as a form of "low-tier" education, constituting repetitive training of simple skills. The purpose of this study is to establish a new vision for future vocational education and seek, accordingly, an appropriate methodology for vocational education in recognition of its importance. First, the author gives an analysis of the origins and characteristics of existing views on vocational education and points out the epistemological and practical limitations of these approaches. Then, an attempt was made to explore a new perspective that can effectively replace the previous outlook on vocational education. Through the formation of a new vision for future vocational education, the impetus was created for the search into new methodologies in vocational education, with which old stereotypes in prior vocational education could be overcome. Thus, this study approaches this problem from a discussion of recent epistemological debates focusing on the tacit character of knowledge.

다중 탐색기반 고속 블록정합 움직임 추정 알고리듬

조영창,최병진,윤정오 경운대학교 산업기술연구소 2000 産業技術硏究論文誌 Vol.3 No.1(B)

Block based fast motion estimation algorithms are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search range we are likely to find local minima instead of the global minimum. This situation is evident in the motion boundary. In this paper we propose the multiple search method. In the proposed method motions are estimated from the many candidate search regions. To reduce the additional search points we reduce the search points using the distance from the initial search point to the recently found vector points. In the simulation the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary in PSNR.

개 대뇌겉질에서 Platelet-Derived Growth Factor α-Receptor의 출생 후 발달에 관한 면역조직화학적 연구

윤영,안병수,김인정,양경철,박선홍,김기훈,박도영,김장만,문정석,장인엽,조하영 조선대학교 부설 의학연구소 2002 The Medical Journal of Chosun University Vol.27 No.1

Background and Objectives : The localization of platelet-derived growth factor-α receptor (PDGF-α R) was commonly restricted to oligodendrocyte progenitors during late embryonic and postnatal development. However, several studies recently demonstrated that mature neurons could also synthesize PDGF-α, Materials and Methods : In the present study, to analyze the distributional pattern of PDGF-αR during postnatal development of the canine cerebral cortex, we used immunohistochemistry on sections of canine brain tissue. Results : We found that neurons of various regions of cerebral cortex exhibited the immunoreactivity to PDGF-αR as early as postnatal day 0, and slightly decreased after postnatal day 14. Whereas neuronal PDGF-αR were maintained at all ages, the oligodendroglia-like expression of PDGF-αR could not be confirmed. Conclusion : The localization of PDGF-αR in immature and mature neurons supports the several roles of PDGF during development, protection and survival of neurons.

천연자원의 간기능 보호 효과에 관한 연구 : Benzo(a)pyrene에 의해 유도된 간기능 장해에 미치는 울금의 효과 The Effect of Curcumae Rhizoma on Benzo(a)pyrene Induced Hepatotoxicity

조수열,윤수홍,이윤경,이정숙 효성여자대학교 부설 한국환경위생연구소 1992 환경위생연구 Vol.2 No.1

우리의 생활환경중 어디에나 존재하는 강력한 간독성유발물 benzo(a)pyrene으로 유도된 간장해에 대한 울금의 예방 및 치료효과를 관찰하여 다음과 같은 결과를 얻었다. 1. 울금 추출물 급여는 B(a)P투여로 증가한 혈청 ALT 와 ALP혈청을 현저히 회복시켰으나 혈청 AST활성은 회복시키지 못하였고, 혈청LDH의 활성은 전 실험군 사이에 유의적인 변화가 없었다. 2. 간조직 및 혈청중의 지질함량 변동은 B(a)P단독투여로 인한 유의성 있는 변화에 대해 단지 혈청중의 HDL-cholesterol과 total cholesterol 함량만이 울금 추출물 투여에 의해 정상범위로 회복되었다. 3. 간조직중의 glutathione 함량은 울금 추출물 투여로 B(a)P 단독투여군에 비해 유의성 있는 회복을 보였고, 과산화지질 함량은 B(a)P 단독투여로 인해 유의성 있게 증가하였으나 울금추출물 급여가 이런 증가를 회복시키지는 못했다. This study was performed to investigate the effect of Curcumae Rhizoma extract on the hepatic detoxication when benzo(a)pyrene, a hepatotoxi-cant, was administrated. The results were as followed : 1. The markedly increased enzyme activities(ALT, ALP) were decreasedby administration the Curcumae Rhizoma extract. 2. Serum HDL-cholesterol and total cholesterol contents were normal inthe Curcumae Rhizoma extract groups. 3. Liver glutathione content were decreased by administration the CurcumaeRhizoma extract. 4. It tended that the curative effects were better than the protective effectsof the Curcumae Rhizoma extract.

Skin entrance dose for digital and film radiography in Korean dental schools

Cho, Eun-Sang,Choi, Kun-Ho,Kim, Min-Gyu,Lim, Hoi-Jeong,Yoon, Suk-Ja,,Kang, Byung-Cheol 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.4

Purpose : This study was aimed to compare skin entrance dose of digital radiography with that of film radiography and to show the dose reduction achievement with digital systems at 11 dental schools in Korea. Materials and Methods : Forty six intraoral radiographic systems in 11 dental schools were included in this study. Digital sensors were used in 33 systems and film was used in 13 systems. Researchers and the volunteer visited 11 dental schools in Korea. Researchers asked the radiologic technician (s) at each school to set the exposure parameters and aiming the x-ray tube for the periapical view of the mandibular molar of the volunteer. The skin entrance doses were measured at the same exposure parameters and distance by the technician for each system with a dosimeter (Multi-O-Meter : Unfors instruments, Billdal, Sweden). Results : The median dose was 491.2 μGy for digital radiography and 1,205.0 μGy for film radiography. The skin entrance dose digital radiography was significantly lower than that of film radiography (p<0.05). Conclusion : Fifty-nine percent skin entrance dose reduction with digital periapical radiography was achieved over the film radiography in Korean dental schools.

적응적 비트평면 분할을 이용한 무손실 쿼드트리의 영상압축

윤정오,조영창,강상욱 경운대학교 산업기술연구소 2002 産業技術硏究論文誌 Vol.5 No.1(B)

The transmission and storage of digital images require an enormous enpenditure of bandwidth and memory resources, necessitating the use of compression schemes can be divided into two categories : lossy coding schemes, and lossless coding schemes. In lossy coding schemes some portion of information is irretrievably lost, while in lossless coding schemes. However, the loss of information may not be acceptable in certain applications, such as transmission and storage of medical or scientific images, high-precision image, preservation of art work and historical documents. In this paper, we propose two lossless image compression methods using quadtree. this skill is composed of three steps : in the first step, we use predictive coding. at this course, we can choice the predictor what we want. Then, the second step, prediction error image be sliced by 1bit, 2bit, 4bit, 8bit. Last step, we apply quadtree coding. Experimental results show that the prpposed method (L-JPEG + GAP + quadtree combination method) is better than L-JPEG and close to GAP in compression ratio.

S. mutans의 固定化에 依한 Insoluble glucan의 製造方法 및 齒面 細菌膜 分解酵素인 α-1, 3 glucanase 生産菌珠 Streptomyces SW-522에 關한 硏究

尹廷洹,趙孝相,金成柱 수원대학교 산업기술연구소 1992 산업기술연구소논문집 Vol.7 No.-

In other to investigate α-1, 3 glucanase from microorganisms for hydrolysis of dental caries, S. muatns was immobilized by cubes of 28% polycrylamide and coated with same polyacrylamide. The insoluble glucan obtained 1.13g per one liter in TH medium with 5% sucrose by PA immobilization of S. muatns, which was very pure by IR and TLC analysis. α-1, 3 glucanase produced by of the Strptomyces SW-522, was developed by treatment with 5% EMS. The new Sw-522 M1 strain obtained, which improved activity of α-1, 3 glucanase.

白血病에서의 c-myc 腫瘍蛋白의 發現樣相에 관한 硏究

조윤정,이갑노 고려대학교 의과대학 1992 고려대 의대 잡지 Vol.29 No.3

To evaluate the relationship between the expression of c-myc oncoprotein and the development of leukemia, flow cytometric analysis (FACScan®) of c-myc oncoprotein using monoclonal antibody was performed in 23 clinical leukemic samples (4 cases of ANLL ; 15 cases of ALL; 3 cases of ALL in complete remission ; 1 case of chronic myelomonocytic leukemia).20 cases of control groups (non-leukemic bone marrow aspirates). & 4 ATCC leukemic cell lines(ATCC CCL 240 HL-60, acute promyelocytic leukemia ; ATCC CCL 213 Daudi, Burkitt lymphoma ; ATCC CCL 243 K-562. Chronic myelogenous leukemia in blast crises ; ATCC CRL 1582 Molt-4, acute T-cell leukemia). The results were summarized as follows. 1. The proportion of myelocytes, basophilic normoblasts. and polychromatophilic normoblasts of the bone marrow aspirate in control group showed weak, but significant correlation with the c-myc oncoprotein staining indices (% positivity of cell staining and/or corrected mean fluorescence intensity, CMFI) (r= 0.35, 0.35, 0.30 respectively). But the proportion of the other immature cells such as blasts, promyelocytes, pronormoblasts, and orthochromic nor-moblasts showed no correlation with the c-myc oncoprotein staining indices. 2. The difference of the percent positivity of c-myc staining in the cells among the immunologic classes of ALL was not significant. But the CMFI of B ALL is significantly higher than that of common ALL or T ALL (F ratio=3.85, p=0.05). 3. The extent of CDl3. CD33, CD34 expression in ANLL showed no correlation with the c-myc oncoprotein staining indices. But that of CD14 expression in ANLL showed negative correlation with CMFI (r= -1.0). 4. There is no significant differences in c-myc oncoprotein staining indices among ANLL, ALL. ALL in complete remission, CMMoL, leukemic cell lines, and control group. 5. The CMFI of c-myc protein staining is high in K-562, Molt-4, HL-60, and Daudi in a decreasing order. From the above findings, it was concluded that ; first, the malignant transformation of the hematopoietic cells require a complex phenomena in addition to the c-myc oncogene expression because the c-myc oncoprotein is present both in the malignant transformation and in the benign proliferation of hematopoietic cells. Secondly, in the hematopoietic malignancy c-myc oncogene expression is not only present in acute promyelocytic leukemia, but also in the other myeloid leukemia and lymphoblastic leukemia. Thirdly, c-myc oncogene expression is diminished in the terminal stage of monocytic differentiation.

교합면 열구 법랑질의 미세구조 및 산부식 형태

조태식,이상호,윤정훈,김수관 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.2

치면열구전색제의 접착력에 영향을 줄 수 있는 교합면 열구 법랑질의 미세구조 및 산부식 형태, 그리고 산부식 형태에 영향을 줄 수 있는 prismless enamel의 존재 여부 및 법랑질의 화학적 조성을 규명하고자 소구치를 대상으로 협설면과 근원심으로 각각 절단하여 열구내의 법랑질 표면과 산부식 형태를 주사전자현미경으로 관찰하고 EDX를 사용하여 법랑질의 화학적 조성을 분석한 결과 다음과 같은 결과를 얻었다. 1. 열구내 법랑질은 대부분이 prismless enamel이 존재하였다. 2. 미성숙 영구치와 성숙된 영구치 간의 열구내 법랑질 표면 구조 및 산부식 형태는 차이가 없었다. 3. 열구 법랑질은 부위 에 관계없이 60초 산부식 이 15초, 30초, 45초에 비해 산부식 효과가 가장 켰으며 15초, 30초, 45초의 산부식 시간에서는 적절한 유지력을 얻을 수 있는 산부식 상이 관찰되지 않았다. 4. 열구 법랑질의 표면을 기계적으로 제거한 경우는 30초의 산부식 시간에서도 60초 산부식 시간에 못지않은 전형적 인 산부식 상이 관찰되었다. 5. 산부식 형태는 주로 rod 주위가 소실된 제 2형의 산부식 상이 관찰되었다. 6. 열구 내 법랑질의 부위별 화학적 조성의 차이는 없었으나 미성숙 영구치와 성숙된 영구치 사이의 칼슘/인 비는 유의한 차이를 보였다. 이상의 연구결과를 종합하면 교합면 열구내 법랑질은 대부분 산에 저항성이 큰 prismless enamel로 덮여 있어 기존에 제안된 15-30초의 산부식 시간으로는 적절한 유지력을 얻을 수 있는 산부식 상을 형성할 수 없다는 사실을 알 수 있다. 따라서 기존의 제안된 산부식 시간에 대한 재고가 필요하며 이와 함께 적절한 산부식 상을 얻기 위한 방안으로 산부식 전bur를 사용하여 열구내 법랑질 표면을 제거해 주는 보조적인 술식에 대한 검토가 필요하리 라 사료된다. The purpose of this study was to compare the effectiveness of mechanical and acid treatment on enamel surfaces for the retention of pit and fissure sealants and evaluate the presence of a prismless layer. The etch pattern produced on enamel from immature and mature premolar teeth extracted with varying period of acid etching using 37% phosphoric acid was examined using a scanning electron microscope(SEM). The composition of each groups was evaluated using an energy dispersive x-ray(EDX) spectroscopy. The result of present study can be summarized as follows: 1. Prismless layer was commonly observed on the fissure enamel in young and mature premolar. 2. There were no differences in micro-structure and etching pattern on fissure enamel between the young and the mature premolar. 3. The most effective etching pattern for retention of pit and fissure sealant was observed in 60 seconds of etching time and no apparent difference of etching pattern was found among 15, 30, and 45 seconds of etching time which showed non-retentive etching patterns. 4. The etching pattern obtained by grinding enamel surface with bur followed by 60 seconds of etching was similar to that of 60 seconds of etching without any pretreatment of fissure surface. 5. Type 2 etching pattern was commonly found on fissure enamel in both young and mature premolar. 6. The calcium content and P/Ca ratio in fissure enamel between the young and the mature premolar were significantly different(PK0.05). But content of calcium, phosphate and P/Ca ratio on various regions of fissure enamel in both young and mature premolar did not showed any difference. Based on these results, prismless layer may negatively influence the retention of pit and fissure sealants. 'Therefore, the mechanical removal of the prismless layer by grinding prior to etching or by prolonged etching time of enamel within the fissure system should result in an improved bonding of a pit and fissure sealant.