• Title/Summary/Keyword: 안창현

Search Result 36, Processing Time 0.027 seconds

Radiographic study of the odontogenic keratocyst (치성각화낭의 방사선학적 연구)

  • Chun Sang-Deuk;An Chang-Hyeon;Choi Karp-Shik
    • Imaging Science in Dentistry
    • /
    • v.35 no.1
    • /
    • pp.51-54
    • /
    • 2005
  • Purpose : To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular odontogenic keratocyst. Materials and Methods : The researchers compared and analysed the clinical and radiological features of 112 cases of mandibular odontogenic keratocyst confirmed by histopathlogic examination. Results : Mandibular odontogenic keratocysts occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These cysts occurred in the mandibular posterior area, angle-ramus area and anterior area $51.8\%$, $31.2\%$ and $17.0\%$ respectively. These cysts had undulating border ($69.6\%$) rather than smooth border ($30.4\%$). Most of these cysts had well-defined hyperostotic border ($94.6\%$). These cysts caused cortical thinning or expansion ($78.6\%$) rather than no cortical reaction ($21.4\%$). Loss of lamina dura was observed in $72.3\%$, displacement of tooth appeared in $35.7\%$ and root resolution appeared in $12.5\%$ of cases. In $71\%$ of cases, displacement of mandibular canal was observed. Internal patterns of lesional radiolucency were even ($61.6\%$) or uneven ($38.4\%$). Conclusion : These results would be helpful in diagnosing of mandibular odontogenic keratocyst. (Korean J Oral Maxillofac Radiol 2005; 35 : 51-4)

  • PDF

Cell Co-culture Method by Patterned Gratt of Thermo-Responsive Polymer (온도응답성 고분자의 패턴상 그래프트를 이용한 공배양법)

  • Bae Jin Suk;Ahn Chang Hyun;Yoon Kwan Han;Kwon Oh Hyeong;Kang Inn-Kyu;Yamato Masayuki;Kikuchi Akihiko;Okano Teruo
    • Polymer(Korea)
    • /
    • v.29 no.3
    • /
    • pp.294-299
    • /
    • 2005
  • Thermo-responsive poly(N-isopropylacrylamide) (PIPAAm) was covalently patterned by masked el electron beam irradiation. Introduction of PIPAAm on tissue culture polystyrene dish was confirmed by ATR-FTIR and ESCA measurements. Hepatocytes were cultured at $37^{circ}C$ on these surfaces. Cells adhered on PIPAAm-grafted domains were detached by reducing culture temperature to $20^{circ}C$. Endothelial cells were then seeded and cultured on the same surfaces. Seeded endothelial cells were selectively attached on hepatocytes detached and PIPAAm-grafted domains and could be co-cultured with hepatocytes on the same culture dishes with clear pattern. This co-culture method enabled long-term co-culture of hepatocytes with endothelial cells.

A Study on Crop Group for Pesticide Efficacy and Crop Safety of Minor Crops (소면적 재배작물의 약효 및 안전성 그룹화 적용 연구)

  • Ahn, Chang-Hyun;Kim, Yong-Hun;Eom, Hoon-Sik;Lee, Gwang-Ha;Ryu, Gab-Hee
    • The Korean Journal of Pesticide Science
    • /
    • v.18 no.4
    • /
    • pp.364-375
    • /
    • 2014
  • This study was carried out to investigate the pesticide efficacy and crop safety among different leafy vegetables applied with foliar spraying under greenhouse and to check extrapolating from some trial data to other minor crops. Leafy vegetables used in this study were: lettuce (Lactuca sativar), leaf broccoli (Brassica oleracea.), chicory (Cichorium intybus.), chinese cabbage (Brassica campestris subsp. napus var. pekinensis), radish (Raphanus sativus), rape (Brassica napus), crown daisy (Chrysanthemum coronarium), edible burdock (Arctium lappa), endive (Cichorium endivia) and mustard greens (Brassica jumcea). Based on the result of control efficacy, all crops were classified into the groups. The results showed the probabilities of extrapolating the control value data of minor crop within the same group. It would be possible to use the pesticides which are already been registered for similar crops to those crops have no registered pesticides.

Study on the nuchal ligament ossification on lateral cephalometric radiograph (측방 두부규격방사선사진에서 발견되는 목덜미인대 골화에 관한 연구)

  • An, Chang-Hyeon
    • Imaging Science in Dentistry
    • /
    • v.39 no.1
    • /
    • pp.7-11
    • /
    • 2009
  • Purpose: The purpose of this study was to assess the prevalence and radiographic characteristics of the nuchal ligament ossification on lateral cephalometric radiographs in Koreans. Subjects and Method: I review and interpreted the lateral cephalometric radiographs from 4,558 patients (1,857 males and 2,701 females, age range from 2 to 79 years) who visited the Kyungpook National University Dental Hospital from January 1, 2008 to February 3, 2009. I grouped the shapes of nuchal ligament ossification as round, rod-like, and segmented shape. And localized the ossification as the involvement of anterior cervical vertebral body. The data were analyzed by using chi-squared test with two-tailed and at a 5% significance level. Results: Among those who showed the nuchal ligament ossification, he mean age of the 143 males was 51.1 and that of the 97 females was 48.0 years. It as not observed completely below teens, and was observed 1% in twenties, 6.1% in thirties, 18.6% in forties, and 26.3% over fifties. It was significantly prevalent in older age group (P<0.01) and in males than females among the same age group (P<0.05). The shapes of nuchal ligament ossification were as follows in order of frequency: rod-like (49.2%), round (30.4%), and segmented (20.4%). The highest involvement of ossification as found at the level of C5 (67.9%), C4 (29.2%), C6 (22.9%), C3 (3.3%), C7 (2.9%), C2 (0.8%), and C1 (0.4%). Conclusion: The nuchal ligament ossifications on lateral cephalometric radiographs were showed as round, rod-like, or segmented shape. The nuchal ligament ossification is often observed after the age of 40 and is observed more frequently in males than females. The highest shape of nuchal ligament ossification was rod-like shape and the highest involvement of cervical spine was C5.

  • PDF

A Study of Decorative Pattern Shown in e Mural Painting of Koguryo Dynasty′s Tomb (고구려고분벽화에 나타난 장식문양 연구)

  • 안창현
    • Journal of the Korean Society of Costume
    • /
    • v.53 no.4
    • /
    • pp.131-148
    • /
    • 2003
  • Mural Painting of Koguryo Dynasty. root of Korean traditional pattern. has 5 types of pattern in its 24tombs: Fire pattern. Sun . Moon pattern, Flying angel pattern. Hill.Tree pattern, Holy animal bird Pattern. These patterns had developed specially in 3 regions that are Hwanghae-region, Pyongan-region, Jipan-region. from 4th-7th Century. A lot of fire pattern has found at Pyongan-region in 5th century. The ceiling right above 'Dori' frequently had the pattern. The pattern is organized in 'Kyoho' method. The sun.moon pattern was shown in Pyongan-region in 5th century. '3-leg bird'. representative of sun, and frog, representative of moon. were drawn in the pattern in 6th century, rabbit was added with frog in the pattern. Flying angel pattern had found most in Jipan region in 5th century. The pattern was not found in 4th century. Two types of the pattern are angels playing $$\mu$ical instruments and angels preying. The hill tree pattern was simple, antique, and immature in the beginning. the pattern had developed with real description as a landscape picture after the beginning. this pattern has been categorized as a landscape painting. Holy animal and bird patternn had placed in supporting rock between ceiling and floor with the mean of protection in after life These pattern, which were previously influenced by Chines culture, were developed with a base of Koguryo own tradition and supported establishment of a characterized Koguryo Cloture. This study will be a basic document for modern fashion industry of 21 century.

Hydraulic experiments on wave amplification at concave corner for rubble mound structures (경사식구조물 오목부 구간의 파랑증폭 실험)

  • Kim, Young-Taek;Ahn, Chang-Hyun;Lee, Jong-In
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.6
    • /
    • pp.3074-3080
    • /
    • 2013
  • Amplification of wave height at concave corner was investigated by three dimensional hydraulic tests. A typical rubble mound structure was tested with two-layer Tetrapod and the slope of 1:1.5. The irregular waves with Bretschneider-Mitsuyasu spectrum were applied to the tests. The center angles of concave corner were 120 degree, 140 degree and 160 degree. According to the test results, the maximum wave height amplification ratio at concave corner was about 1.5 times of incident wave height among the all test conditions, and the W-shaped wave height distribution was shown.

Efficacy of panoramic radiography as a screening procedure in dental examination compared with clinical evaluation (구강검진에서 임상검사와 비교한 파노라마방사선사진의 유용성)

  • An, Seo-Young;An, Chang-Hyeon;Choi, Karp-Shik
    • Imaging Science in Dentistry
    • /
    • v.37 no.2
    • /
    • pp.83-86
    • /
    • 2007
  • Purpose : To evaluate the efficacy of panoramic radiography by comparing the results of clinical examination with radiographic findings. Materials and Methods: We studied 190 patients (20 men and 170 women; mean age, 40 years; range, 22 to 68 years) who visited the health promotion center of Korea Medical Science Institute and were examined both clinically and by panoramic radiography. We compared results from both examinations. Treatment options by clinical examination were described as "no treatment indicated", "treatment of dental caries", "removal of calculus", "treatment of periodontal disease", "prothodontic treatment" and "extraction of the third molar". Findings taken from the panoramic radiography were: dental caries, periapical lesion, alveolar bone loss, calculus deposition, retained root, impaction of the third molar, disease of maxillary sinus, bony change of mandibular condyle, etc. Results: The prevalence of panoramic findings were: 37.9% of dental caries, 17.4% of periapical lesions, 44.7% of alveolar bone losses, 62.6% of calculi deposition, 7.9% of retained roots, 26.8% of third molar impactions, 6.3% of diseases of maxillary sinus, 2.1 % of bony changes of mandibular condlye and 35.8% of miscellaneous lesions. Abnormal conditions revealed by panoramic radiography which had not been discovered on clinical examination were: 24.2% of the patients had dental caries, 17.4% had periapical lesions, 7.4% had calculi deposition, 5.3% had retained roots, 15.3% had third molar impactions. The opposite cases were: 5.2% had dental caries, 12.6% had calculi deposition, and 9.5% had third molar impactions. Conclusion: The use of panoramic radiography as a supplement to the clinical examination might be a valuable screening technique.

  • PDF

Radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst: with emphasis on CT (법랑모세포종과 치성각화낭의 방사선학적 감별진단 : CT를 중심으로)

  • Soh Byung-Chun;Heo Min-Suk;An Chang-Hyeon;Choi Mi;Lee Sam-Sun;Choi Soon-Chul;Park Tae-Won
    • Imaging Science in Dentistry
    • /
    • v.32 no.3
    • /
    • pp.167-173
    • /
    • 2002
  • Purpose : To evaluate clinical and radiographic differential diagnosis between ameloblastoma and odontogenic keratocyst (OKC) using clinical data, plain radiographs, and CT. Materials and Methods: 25 cases of ameloblastoma and 44 cases of OKC diagnosed in biopsy, were selected from the files stored in Department of Oral and Maxillofacial Radiology, Seoul National University Dental Hospital from 1999 to 2001, and evaluated using following criteria: sex and age, location, shape, border to normal bone tissue, effect to adjacent tissues, homogeneity in the lumen of the lesion, response of the cortical bone, long-to-short length (LIS) ratio of the lesion, and expansion angle of the cortex. Results: Ameloblastoma and OKC were seen most frequently in third decades and no statistical significance was noted between both sexes. Ameloblastoma occurred most frequently in mandibular angle and ramus area (68%) and OKC at the maxillary molar (34.1 %), and mandibular angle and ramus area (43.2%). The root resorption of the adjacent teeth, mandibular canal displacement, and the impaction of teeth were seen more frequently in ameloblastoma than in OKC. The LIS ratio measured in CT was largest in maxillary OKC cases, followed by mandibular ameloblastoma, and mandibular OKC (1.2, 1.8 and 2.4 respectively). The expansion angle of the cortex shows a statistically significant difference between ameloblastoma (48.8°) and OKC (31.5°). Conclusion : The numeric morphology (LIS ratio) and expansion angle of the cortical bone of the lesion measured in computed tomography can be used to differentiate the ameloblastoma and odontogenic keratocyst.

  • PDF

The relationships between panoramic indices and dental implant failure (파노라마방사선사진 지수와 임플란트 실패와의 관계에 관한 연구)

  • Cho Hyun-Jung;Yi Won-Jin;Heo Min-Suk;An Chang-Hyeon;Lee Jin-Koo;Lee Sam-Sun;Choi Soon-Chul
    • Imaging Science in Dentistry
    • /
    • v.34 no.1
    • /
    • pp.25-30
    • /
    • 2004
  • Purpose: Several panoramic indices have been suggested to assess bone quality from the morphology and width of mandibular cortex on panoramic radiography. The purpose of this study was to compare dental implant failure group with control group in panoramic mandibular index (PMI), mandibular cortical index (MCI), and gonion index (GI) and to determine the effect of these panoramic indices on dental implant failure. Materials and Methods: A case-control study was designed. Test group (n=42) consisted of the patients who had their implants extracted because of peri-implantitis. Control group (n=139) consisted of the patients who retained their implants over one year without any pathologic changes and had been followed up periodically. They had dental implants installed in their mandibles without bone augmentation surgery from 1991 to 2001. The following measures were collected for each patients: 1) PMI, MCI, and GI were measured twice at one-week interval on preoperative panoramic views; and 2) age, sex, implant length, implant type, installed location, occluding dentition state, and complication were investigated from the chart record. Results: The PMI showed moderate level of repeatability. The intra-observer agreement of MCI and GI were good. There was statistically significant difference in PMI between two groups. There were significant different patterns of distribution of MCI and GI between two groups. Among the panoramic indices, PMI and MCI showed significant correlation with dental implant failure. Conclusion: Panoramic indices can be used as reference data in estimating bone quality of edentulous patients who are to have implants installed in their mandibles.

  • PDF

3-D Rat Hepatocytes' Culture on Polystyrene Nanofibrous Scaffold (폴리스티렌 나노섬유상에서의 간세포의 3차원 배양)

  • Kim, Young-Jin;Ahn, Chang-Hyun;Oh, Hwan-Hee;Kim, Young-Jin;Yoon, Kwan-Han;Kang, Inn-Kyu;Kwon, Oh-Hyeong
    • Polymer(Korea)
    • /
    • v.32 no.2
    • /
    • pp.131-137
    • /
    • 2008
  • We have fabricated polystyrene (PS) nanofibrous scaffold for hepatocyte culture by electrospinning method and subsequently coated with specific ligand of Poly[N-p-vinylbenzyl-O-$\beta$-D-galactopyranocyl-($1{\rightarrow}4$)-D-gluconamide](PVLA) to enhance hepatocytes attachment. Rat hepatocytes behavior on the PVLA-coated and non-coated PS nanofibrous matrices have been investigated. Electrospun PS nanofiber structures revealed randomly aligned fibers with average diameter of 500 nm. It is observed that PS nanofibrous matrix could incorporate many cells into the interior of the matrix probably due to the suitable pore size. Cell viabilities cultured on PVLA-coated PS nanofibrous mats were maintained for 3 weeks, while it was decreased rapidly on PVLA-coated PS dishes. High hepatic functions especially for albumin secretion and ammonia removal were maintained at least for 2 weeks on nanofibrous mats but rapidly decreased on flat PS dishes. These results indicate that nanofibrous structure enabled 3-D culture with high level of cell-cell contact results in providing cell-cell communications and subsequent long-term maintenance of specific cell functions.