Collagenase와 esterase가 상아질 접착강도와 nanoleakage에 미치는 영향

정영정,한세현,김종철,이상훈,김정욱,김영재,장기택 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.3

본 연구는 상아질 접착계면에서 collagenase와 esterase가 접착강도와 극미세누출에 미치는 영향을 살펴보기 위해 시행하였다. 발치된 치아의 교합면 상아질에 Single Bond 2(SB)와 Clearfil SE bond(SE)를 사용하여 상아질-레진 접착시편을 제작하고,시편을 인산완충용액(PBS)에 24시간(I),또는 PBS(II),collagenase 용액(III),esterase 용액(IV)에 4주간 보관 한 후 질산은 용액으로 염색하였다. 시편의 미세인장접착강도(μTBS)와 질산은 침투 면적을 측정하여 다음과 같은 결과를 얻었다. 1. SB군의 접착강도가 II∼IV군에서 SE군에 비해 낮은 값을 나타내었다(p<O.05). SB군은 II∼IV군의 접착강도가 I군에 비해 낮은 값을 보였으나(p<O.05),SE군의 접착강도는 I∼IV군간에 차이를 보이지 않았다(p>O.05). 2. SB군의 질산은 침투 면적이 SE군에 비해 높았으며(p<O.05),SB군과 SE군에서 질산은 침투 면적은 I ∼ IV군간에 차이를 보이지 않았다(p>O.05). 3. 접착강도와 질산은 침투 면적은 SE군의 I, II,III군에서 음의 상관관계를 보였다(p<O.05). The purpose of this study was to evaluate the effects of collagenase and esterase on dentin bond strength and nanoleakage. Resin composites were bonded to occlusal dentin of premolars with Single Bond 2(SB) and Clearfil SE Bond(SE). After the microtensile specimens were prepared and stored in PBS for 24 hours(I) or, PBS(II), collagenase(III), esterase(IV) solution for 4 weeks, the specimens were stained with silver nitrate solution. Microtensile bond strength(μTBS) and silver penetration area were measured and, the results were as follows: 1. For group II, III, and IV, the bond strengths of SB were lower than those of SB(p<0.05). The bond strengths of SB II, III, and IV were lower than that of SB I(p<0.05). There was no difference among the bond strengths of SE I ∼ IV groups(p>0.05). 2. Silver penetration areas of SB were higher than those of SE for all storage groups(p<0.05). In SB and SE groups, there was no significant difference of silver penetration area among I ∼ IV groups(p>0.05). 3. SE I, II, and III showed inverse relationship between the bond strengths and the silver penetration areas(p<0.05).

상아질 접착에서 collagenase와 esterase가 미세인장결합강도에 미치는 영향

정영정,현홍근,김영재,김정욱,이상훈,김종철,한세현,장기택 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.2

상아질-레진 접착강도에 대한 collagenase와 esterase의 영향을 살펴보기 위해, 소구치의 교합면 상아질에 Single Bond 2와 Clearfil SE Bond로 접착을 시행하고 미세 시편을 제작하여 PBS, collagenase 용액, esterase 용액에 4주간 보관한 후 미세인장결합강도를 측정, 비교하여 다음과 같은 결론을 얻었다. 1. 모든 보관 용액에서 Single Bond 2의 미세인장결합강도는 Clearfil SE Bond보다 유의하게 낮았다(p<0.05). 2. Single Bond 2의 미세인장결합강도는 collagenase군이 PBS군, esterase군보다 낮았다(p>0.05). 3. Clearfil SE Bond의 미세인장결합강도는 esterase군이 PBS군에 비해 낮았으나(p>0.05), collagenase군보다는 높았다(p>0.05). Collagenase군은 PBS군에 비해 유의하게 낮은 미세인장결합강도를 보였다(p<0.05). The purpose of this study was to evaluate the effect of collagenase and esterase on the microtensile bond strength (μTBS) in dentin bonding. After resin composites were bonded to occlusal dentin, μTBS specimens were formed and stored in PBS, collagenase, or esterase solution. After 4-week storage, μTBS was determined and, the results were as follows: 1. μTBS values of Single Bond 2 were lower than those of Clearfil SE Bond for all storage medium (p<0.05). 2. In single Bond 2 group, collagenase solution lowered bond strength more than PBS and esterase solution (p>0.05). 3. In Clearfil SE Bond group, esterase solution lowered bond strength more than PBS(p>0.05). Collagenase solution lowered bond strength more than esterase solution(p>0.05) and PBS(p<0.05).

나노 충전제 함량에 따른 복합레진의 표면 미세경도 차이

정영정,김연재,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.1

최근에 개발된 나노 충전제를 microhybrid 복합레진에 첨가할 때, 나노 충전제 함량이 중합에 미치는 영향을 조사하기 위해, 실험적으로 나노 충전제의 함량을 다르게 제작한 복합레진에서 광중합 후 미세경도를 측정, 분석하여 다음과 같은 결론을 얻었다. 1. 나노 충전제의 함량이 2%, 3%인 군은 0%, 1%인 군에 비해 중합된 면의 미세경도가 유의하게 높았으나(p<0.01), 그 차이는 크지 않았다. 2. 나노 충전제의 함량이 높을수록 레진 시편의 하면에서의 미세경도는 증가하였으며, 나노 충전제의 함량이 0%, 1%, 2%간에, 0%, 1%, 3%간에 유의한 차이가 있었고(p<0.01), 2%와 3%간에는 차이가 없었다(p<0.05). 3. 레진 시편의 상면과 하면의 미세 경도 차이는 나노 충전제 함량이 높을수록 감소하였으며, 나노 충전제의 함량이 0%, 1%, 2%간에, 0%, 1%, 3%간에 유의한 차이가 있었고(p<0.01), 2%와 3%간에는 차이가 없었다(p<0.05). The objective of this study was to evaluate the effects of nanofiller content on the microhardness and polymerization of experimental microhybrid composites. The nanofiller contents in the experimental composites were varied (0%, 1%, 2%, 3%), while the total filler content remained constant as 76 %wt. We obtained the following results: 1. The microhardness of the top surface for the 2%, 3% nanofilled microhybrid composites were significantly higher than those for the 0%, 1% nanofilled composites (p<0.05), but the difference was not great. 2. The microhardness of the bottom surfaces significantly increased with an increase in the nanofiller level (p<0.05), except between the 2% and 3% nanofilled groups (p>0.05). 3. As the nanofiller level increased, the difference beween microhardness of top and bottom surfaces significantly decreased (p<0.05), except between 2% and 3% nanofilled groups (p>0.05).

복강내에 발생한 다발성 혈관종 : 증례 보고

정갑중,김형호,최홍조,김영훈,조세헌,정진숙,남경진,김상순 동아대학교의과대학 1992 동아의대학술지 Vol.4 No.1

정전기력 구동 마이크로 액츄에이터를 이용한 Si 소재 탄성특성의 온도의존성 평가

鄭聖勳,李世昊,鄭增鉉,權東一 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.8

Electrostatically actuated testing devices were used to estimate the elastic modulus of single-crystalline Si for microeletromechanical systems. The devices were moved laterally by alternating electrostatic force at a series of frequencies, and then a resonance frequency was determined, with temperature cycling, by detecting the maximum displacement. The elastic modulus was calculated from the detected resonance frequency by Rayleigh's energy method. The elastic modulus decreased with heating and then increased with cooling, but after thermal cycle the specimen showed a permanent change to a value lower than the initial one. This phenomenon can be explained, to some extent, by the temperature-dependent variation in interatomic force of Si atoms, but the permanent change in elastic modulus implies that it may also be caused by the formation of a thermal oxide layer on the Si with increasing temperature. Composite bending theory was invoked to analyze the oxide effect and the thickness of the oxide layer formed during thermal cycling was estimated from the permanent change in the resonance frequency. The existence of the oxide layer was confirmed by field emission scanning electron microscopy. Finally, the method for compensating the decreasing elastic modulus with increasing temperature were proposed by using the temperature coefficient of elastic modulus.

서울대학교치과병원 장애인진료실에서의 치과치료 분석

이현정,김영재,김정욱,장기택,이상훈,김종철,한세현 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.2

전신마취하에서의 치과치료는 자발적인 협조가 불가능하거나 전신적인 문제가 있는 경우, 다수의 치료를 한 번에 하고자하는 경우 등에 행해진다. 이 연구는 서울대학교치과병원 장애인진료실에서 외래 전신마취하에 행해진 환자와 치과치료를 분석함으로써 보다 나은 장애인 진료 시스템을 위한 방안 제시에 도움이 되고자 하였다. 2002년 6월 11일부터 2006년 12월 31일까지 장애인진료실에서 치료 받은 432명의 환자들을 대상으로 조사한 결과 15세 이하의 환자가 50.46%로, 소아 및 청소년 환자가 높은 비율을 차지하고 있었다. 진료과는 보존과, 소아치과, 구강외과, 치주과, 보철과 순으로 나타났으며 치료내용을 보면 보존치료와 발치가 주를 이루고 있었다. 또 2회 이상 전신마취를 시행한 환자가 14.1%나 되었다. 본 연구는 장애인 환자를 위한 보다 포괄적인 치과 치료 및 진료과들 간의 긴밀한 협진 체계를 구축하고 필요한 인력과 설비를 보충함으로써 장애인 환자들에게 보다 보존적인 치과치료와 편안한 치료 환경을 제공해야 할 필요성을 제시하고 있다. Seoul National University Dental Hospital opened The Clinic for The Disabled to provide dental treatment under outpatient general anesthesia. 432 patients underwent general anesthesia for dental treatment. The informations such as the pattern of dental treatment, the reasons of general anesthesia, the characteristics of the patients were analyzed. Followings are concluded. 1. The patients below 15 years old made up 50.60%. 2. The reasons for general anesthesia included mental and physical disabilities, systemic disease, dental phobia, and so on. 3. Restorative treatment was the most common procedure with the average of 9.7 teeth treated per one patient. 4. 62(14%) patients underwent general anesthesia for dental treatment more than once. 5. The efforts for better multidisciplinary system to provide more comprehensive and effective dental treatment including periodic recall check, preventive treatment for handicapped patients are necessary.

선양치성종양으로 오진하여 수 차례 재발한 상악동의 선방세포암종

윤정훈,조세인,김수관 大韓顎顔面成形再建外科學會 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.6

A 46-year-old male appealed severe palatal and buccal swelling in the Lt. maxilla in 1990. In 1986, the patient was already carried out the clinical and radiological examination in our hospital. Multiple radiolucency was seen from #21 to #25 periapical area and Lt. maxillary sinus in the panoramic view at this time. But, the patient came home without special examination or inspection for itself. January 1990, the mass took an impression to grow bigger and the patient had visited again. Partial maxillectomy was carried out at this time and pathologic diagnosis was an adenomatoid odontogenic tumor. After 3 years, lesion was recurred and carried out hemimaxillectomy with Weber-Furgusson incision. September 2001, facial swelling was recurred again and patient was suffered from nasal breathing, lacrimal obstruction and exopthalmus. In this case, the tumor cells composed of nodular and papaillary cystic pattern with microcyst formation, highly suggestive of an adenomatoid odontogenic tumor. Histopathologically, the recurrent tumor was proved to be the same pattern of the primary tumor, which is compatible with acinic cell carcinoma. However, adenomatoid odontogenic tumor did not appear destructive multilocular radiolucency. In addition, this tumor had frequently observed amyloid-like or calcified materials in biopsy specimen. Therefore, oral pathologists had kept in mind into the correlative analysis of histopathologic and oral radiographic features, which is essential for definitive diagnosis.

Polyimide 기판을 이용한 Flexible CIGS 박막 태양전지 제조

정승철(Jung, Seung-Chul),안세진(Ahn, Se-Jin),윤재호(Yun, Jae-Ho),곽지혜(Gwak, Ji-Hye),김도진(Kim, Do-Jin),윤경훈(Yoon, Kyung-Hoon) 한국신재생에너지학회 2009 한국신재생에너지학회 학술대회논문집 Vol.2009 No.06

In this study, we fabricated the Cu(In,Ga)Se₂ (CIGS) thin-film solar cells by using a polyimide substrate. The CIGS thin-film was deposited on Mo coated polyimide substrate by a 3-stage co-evaporation technique. Because the polyimide shows thermal transformation at about 400?C, the substrate temperature of co-evaporation process was set to below 400?C. Corresponding solar cell showed a conversion efficiency of 7.08 % with V_{OC} of 0.58 V, J_{SC} of 24.99 mA/cm² and FF of 0.49.

UV/H2O2 광산화공정을 적용한 원전 발생 방사성 폐액내 세제 처리

박은정,이지훈,박세문 대구대학교 환경기술연구소 2004 미래환경기술 Vol.1 No.1

원전 발생 방사성 폐액 내 세제를 제거하기 위한 전처리 공정으로 UV 광산화 공정을 활용하기 위하여 공정의 효율 및 적용 가능성에 대한 기초 실험을 수행하였다. 최적 처리조건을 도출하고자, 방사성 폐액의 평균 세제 함유량 (TOC 50∼100ppm)을 기준으로 모의폐액을 제조하여 과산화수소 주입량에 따른 세제 제거율, pH 변화에 따른 세제 제거율, 공기 공급량에 따른 세제 제거율을 도출하였다. 실험결과로서 과산화수소 주입량은 1000ppm, pH는 9.5일 때 최적 분해율을 보였고 공기 공급량의 영향은 받지 않는 것으로 밝혀졌다. 광분해 특성 규명을 위한 회분식 광분해 실험 결과, 광분해 반응 차수는 2차 반응임을 알 수 있었다. To apply the UV-photo oxidation process for the removal of detergent contained in the radwaste generated from the NPP, the effectiveness and feasibility were studied through the fundamental experiments. The simulants with TOC 50∼100ppm made of detergent were used for the lab-test. The optimum detergent removal rates due to the hydrogen peroxide volume, pH and air injection volume were investigated. The detergent removal rate was optimum at 1000ppm of hydrogen peroxide volume and at pH 9.5, while the air injection volume was not that much effective. The experimental result showed that the photo-oxidation degradation under the batch mode was of the second reaction.

반복가열냉각에 의한 수화시멘트 페이스트와 골재 분리 방법

김세훈,임승준,안재철,오상균,김정길 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

Cement mortar and efficient disconnection of aggregate are indispensable for recycling of waste concrete, and the problem is with quality in the existing physical disconnection way, and the problem has been by application of a concrete recycling construction materials. Specially, in case of recycled aggregate, the quality is lowered because of the fine aggregate powder which has a bad influence on flowability, a compression strength by adhesion of mortar on the aggregate face, and the case of recycled cement was added to during recycle cement. Therefore, a mortar and interfacial separation of aggregate are large in proper quality for concrete recycling is expected that affect. This study based on the recycled cement manufacturing way which used an aggregate interfacial separation of waste mortar in this study so that the coefficient of thermal expansion of hardend cement paste and an the coefficient of thermal expansion of a fine aggregate are different in a recycled cement manufacturing way, but leaves a purpose.