감압술을 이용한 치근단 낭의 처치

김남혁,최병재,이제호,손흥규,김성오,최형준 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.2

치근단 낭은 염증 등에 의한 자극으로 치수가 실활되어 치근단에 있는 상피로부터 형성되는 낭종으로 주된 기원은 말라세즈 상피잔사이지만 치은열구 상피나 상악동 이장 상피, 누공의 상피에 의한 것도 보고 되었다. 구강악안면 영역에서 가장 흔히 발생되는 낭종의 하나이지만 유치열기에서의 발생 빈도는 낮은 것으로 알려져 있다. 악골 내의 치성 낭종은 크기가 커지면서 주위 조직의 파괴나 구조의 변형을 초래할 수 있으며 유치의 경우에서는 후속 영구치배의 변위를 유발할 수 있다. 이런 큰 크기의 치성 낭종을 외과적으로 제거하면 해부학적 구조의 손상 및 안모의 변형, 치아흡수, 신경손상 등의 후유증을 일으킬 수 있으므로 조대술이나 감압술 후 적출하는 술식이 권장되고 있다. 이 증례는 하악 우측 부위의 동통을 주소로 연세대학교 치과대학병원 소아치과에 내원한 8세 남아로, 임상 및 방사선학적검사 결과 치수치료 후 기성금속관의 수복을 시행한 하악 우측 제1유구치의 치근단 하방에 방사선투과성 병변과 견치와 제1소구치의 변위를 발견하였다. 병소가 있는 하악 우측 제1유구치를 발거하였고, 조직학적 검사에서 치근단 낭으로 진단되었다. 감압술 및 공간유지장치를 시행하고 병소의 크기 변화와 하악 우측 견치와 제1소구치의 맹출 양상을 정기적으로 관찰한 결과 양호한 치유 양상과 정상적인 맹출을 보였기에 이를 보고하고자 한다. Radicular cyst is a true epithelium lined cyst formed when epithelium at the apex of a nonvital tooth is stimulated by inflammation. It is the most common type of cyst in the oral cavity, but its frequency is low in the primary dentition. Treatment of large-sized cyst aims at conservation of adjacent structure and allowance of proper eruption of the successive permanent teeth in the primary dentition. Considering these two aspects, marsupialization or enucleation following decompression is recommended as a treatment means for large-sized radicular cyst. In this case, 8-year old boy visited the pediatric dentistry department, Yonsei University Dental Hospital, with the chief complaint of pain on the lower right area. Clinical and radiographic examinations revealed periapical radiolucent lesion on #84, which had previous pulp treatment and restorated with the stainless steel crown. Dislocation of its successive tooth, #44, was also observed. #84 was extracted and sent for biopsy. Through histologic examination, it was diagnosed as radicular cyst. Following its extraction, removable space maintainer was delivered, which was also used as a decompressor. During periodic check-up for next 22 months, favorable healing of the lesion and eruption of the successive tooth were observed.

세계화와 지식기반사회에서의 경제교육 내용 구성 방안

최병모,이준혁 한국경제교육학회 2004 경제교육연구 Vol.11 No.1

매복된 상악 중절치의 교정적 처치를 통한 치험례

김남혁,김성오,송제선,손흥규,최병재,이제호,최형준 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.1

매복은 임상 검사나 방사선 사진 검사 상에서 인식 가능한 맹출 경로 상에 장애물이나 이소 위치에 의한 치아 맹출의 정지를 의미한다. 상악 중절치의 치아 매복의 원인으로는 과잉치, 치아종, 치배의 이소위치, 외상 후 연조직 치유에 의한 폐쇄, 만곡치, 정지된 치근 발육 등이 있다. 매복된 치아는 인접치의 근심이동으로 인한 공간 상실, 부정교합, 인접치의 치근 흡수, 낭종의 형성 등을 유발할 수 있으므로 맹출장애에 대한 주의 깊은 관찰과 조기 진단이 중요하며 적절한 치료가 시행되어야 한다. 매복된 치아의 치료방법으로는 유치의 발거나 외과적 노출을 통한 맹출 유도, 경과관찰, 외과적 방법이나 교정력을 이용한 매복치의 재위치, 매복치의 외과적 발거 등이 있다. 이 중 교정적 견인은 매복된 치아가 원인을 제거한 후 또는 외과적으로 치관을 노출시킨 후에 일정기간의 관찰에도 맹출하지 않거나, 맹출경로가 정상에서 많이 벗어나 맹출이 기대되지 않을 경우 적용될 수 있다. 본 증례는 매복된 상악중절치를 교정적 견인을 통해 정상적인 맹출 방향으로 유도한 치험례들로 양호한 치료 결과를 보였기에 이를 보고하고자 하는 바이다. Impaction is defined as a cessation of the eruption of a tooth caused by a clinically or radiographically detectable physical barrier in the eruption path or by an ectopic position of the tooth. The reasons for impaction of the maxillary central incisor are supernumerary tooth, odontoma, ectopic position of tooth germ, dilacerated tooth and so force. Impacted tooth cause space loss due to proximal movement of adjacent tooth, malocclusion, root resorption of adjacent tooth, cyst formation, so careful observation and early detection is important and exact treatment should be applied to prevent these results. The treatment options of impacted tooth include induction an eruption through extraction of deciduous tooth or surgical exposure, reposition of impacted tooth by surgical method or orthodontic treatment. Orthodontic traction is recommended when an eruption does not happen after removal of barrier or surgical exposure, when eruption path is too transpositioned to be corrected spontaneously so eruption does not expected. In these cases, traction of impacted maxillary central incisor was carried out using orthodontic method with closed eruption technique and it showed good clinical results so we report these cases.

학교 경제교육 방향 탐색을 위한 델파이 조사 연구

최병모,김정호,이준혁 한국경제교육학회 2005 경제교육연구 Vol.12 No.1

Ce_(0.8)Zr_(0.2)O₂ 촉매를 이용한 Dimethyl Carbonate 합성에서 탈수제 첨가의 영향

한기보,전진혁,박노국,이종대,류시옥,이태진,이병권,안병성 한국공업화학회 2004 응용화학 Vol.8 No.1

The effect of dehydrating agent in DMC(dimethyl carbonate) synthesis from methanol and carbon dioxide over Ce_(0.8)Zr_(0.2)O₂ catalyst was studied in this work. Ce_(0.8)Zr_(0.2)O₂ catalyst having the best activity among Ce_(1-x)Zr_(x)O₂ catalysts was selected. We could supposed that the addition of dehydrating agents improved the DMC yield by H₂O elimination. When the dehydrating agents such as Na_(2)SO₄ or K₂SO₄ was added into the synthesis of DMC, the formation amount of DMC increased to about 0.8∼0.9 mmol through the elimination of formed H₂O as by-product.

Si Bulk Micromachining을 위한 Wafer Rolling Etching 및 그 특성

김건년,이보나,박효덕,신상모,공경준,장동근,김병철,권혁채,이봉희 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

A wafer rolling etching system for the silicon bulk micromachining has been designed and fabricated. The silicon diaphragms were anisotropically etched in a 24.5 weight percent KOH solution. Compared to the conventional KOH etching systems, pyramidal hillocks, and wave-shaped structures on the etched surfaces were greatly reduced by using this system. After etching for time of 438 minutes, the average etched depth and the etch-rate were measured to be 537μm and 1.22μm/min, respectively. The average etching uniformity of etching depth was 0.87% in 5-inch wafer. Our results showed that the wafer rolling method enhanced etch uniformity and etch rate.

개에서 이중 결찰법을 통한 동맥관 개존증의 완치 예

윤헌영,정순욱,박희명,박철,정만복,김준영,한현정,황민,노병국,박상혁,장하영,박정윤 한국임상수의학회 2004 한국임상수의학회지 Vol.21 No.1

A ten months old, female Yorkshire terrier weighing 2.88 kg referred to veterinary teaching hospital of college of veterinary medicine, Konkuk University because of syncope, cough and dyspnea. First hematological and serum chemical test revealed thrombocytopenia, mild anemia, and increase of concentration of ALP (195 U/L). On 57 days later, second hematological and serum chemical test revealed polycythemia, increase of concentration of ALP (211 U/L), and Tchol (387 mg/dl). Right atrium enlargement, main pulmonary artery bulge and cardiomegaly (VHS = 11.5) were observed in radiographic findings. Ultrasonographic images showed both right and left ventricular dilation and turbulent flow between the descending aorta and the main pulmonary artery in color Doppler imaging. ECG showed left ventricular enlargement, SA block, and electrical alternant. Thoracotomy was performed through left fourth intercostal incision under isoflurane anesthesia. Patent ductus arteriosus was double ligated with 1-0 silk. Cough and dyspnea disappeared on 5 days after operation. Turbulent flow was not found in color doppler imaging of ultrasonography on 10 days after operation. Ten months later after the operation, syncope could not exist any more.

Effect of Mg content on the density and critical properties of in-situ reacted MgB₂ bulk superconductor

Jun, Byung-Hyuk,Kim, Dan-Bi,Park, Soon-Dong,Kim, Chan-Joong 한국초전도저온공학회 2014 한국초전도저온공학회논문지 Vol.16 No.1

The effects of Mg content on the pore formation, density and critical properties were investigated in in-situ reacted $MgB_2$ superconductors. The $Mg_{1+x}B_2$, (x=-0.2, 0.0, 0.05, 0.3, 1.0) bulk samples with different Mg contents were heat-treated at $900^{\circ}C$ for 1 h in an Ar atmosphere. The dimensional changes of a pellet's mass and volume after heat-treatment were measured. After heat-treatment process, the sample mass was decreased by Mg evaporation, but the sample volume was expanded by pore formation at the Mg site; therefore, the apparent density was decreased. Spherical pores the same as Mg particles were developed after heat-treatment in all samples, and the pore density was increased with increasing Mg content. As the x of Mg content was increased to 1.0, the apparent density of $Mg_{1+x}B_2$ samples was decreased due to a relatively larger reduction in a mass change. The critical current density of Mg excessive sample of x=0.05 showed the highest values over the applied magnetic fields because the excessive Mg may compensate Mg loss and enhance grain connectivity.

Particle Distribution in Melt-textured Y-Ba-Cu-O Superconductors

Jun Byung-Hyuk,Mahmood Asif,Park Soon-Dong,Kim Chan-Joong 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

The effect of heat-treatment temperature on the superconducting properties of malic acid-doped MgB₂<i>/</i>Fe wire

Jun, Byung-Hyuk,Kim, Chan-Joong IOP Publishing Ltd 2007 Superconductor science & technology Vol.20 No.10

<P>The effects of the heat-treatment temperature on the carbon (C) substitution amount, full width at half-maximum (FWHM) value, critical temperature (<I>T</I><SUB>c</SUB>), critical current density (<I>J</I><SUB>c</SUB>), irreversibility field (<I>H</I><SUB>irr</SUB>) and upper critical field (<I>H</I><SUB>c2</SUB>) have been investigated for 10 wt% malic acid-doped MgB<SUB>2</SUB>/Fe wires. All the samples were fabricated by the <I>in situ</I> powder-in-tube (PIT) method and heat-treated within a temperature range of 650–1000 °C. As the heat-treatment temperature increased, it seemed that the lattice distortion was increased by a more active C substitution into the boron (B) sites from the malic acid addition. These increased electron scattering defects seemed to enhance the <I>J</I><SUB>c</SUB>–<I>H</I> properties in spite of an improvement in the crystallinity, such as a decrease of the FWHM value and an increase of the <I>T</I><SUB>c</SUB>. Compared to the un-doped wire heat-treated at 650 °C for 30 min, the <I>J</I><SUB>c</SUB>, <I>H</I><SUB>c2</SUB> and <I>H</I><SUB>irr</SUB> were enhanced by the C doping in a high-field regime. The wire heat-treated at 900 °C resulted in a higher magnetic <I>J</I><SUB>c</SUB> of approximately 10<SUP>4</SUP> A cm<SUP>−2</SUP> at 5 K and 8 T, and it showed a <I>H</I><SUB>irr</SUB> value of 11 T at 20 K from the resistance (<I>R</I>) versus temperature (<I>T</I>) curves. </P>