3차원 전산화 단층촬영의 Nasion, Sella, Basion으로 구성된 정중 시상 평면과 정면 두부방사선 규격사진의 정중 시상 평면 비교

조진형,문지연 대한치과교정학회 2010 대한치과교정학회지 Vol.40 No.1

안면 비대칭의 평가에 있어 과거 정면 두부방사선 규격사진을 이용하던 것과는 다르게 현재는 점차 3D CT를 이용하여 평가하는 것으로 변하고 있다. 본 연구는 3D CT와의 비교를 이용하여 정면 두부방사선 규격사진 분석에서 쉽게 접근할 수 있는 시상 기준 평면을 찾고자 하였다. 임상적으로 안모 비대칭이 발견되지 않은 성인 환자들을 대상으로 3D CT와 정면 두부방사선 규격사진을 촬영하였고, 정면 두부방사선 규격사진 분석에서 이용되어 왔던 5가지 정중 시상 기준 평면을 선택하여 계측을 실시한 뒤 이 값을 3D CT의 Nasion (Na), Sella (S), Basion (Ba)으로 구성된 정중 시상 평면에 대한 계측값과 비교하였다. 그 결과 좌우측 latero-orbitale의 수직이등분선을 정중 시상 기준 평면으로 이용한 정면 두부방사선 규격사진 계측값이 3D CT의 Na, S, Ba으로 구성된 정중 시상 평면을 이용한 계측값과 가장 차이가 작았고 상관관계가 높은 것으로 나타났다. 안면 비대칭 평가 시 좌우측 latero-orbitale의 수직이등분선이 정면 두부방사선 규격사진 분석에서 도움이 되는 정중 시상 기준 평면으로 이용될 수 있을 것이다. Objective: The aim of this study is to find the most helpful midsagittal reference plane for diagnosis in PA cephalometry compared with 3D CT. Methods: The subjects consisted of 25 adults who showed no facial asymmetry by gross inspection. 3D CT and posteroanterior cephalogram of the subjects were taken. To find the most helpful midsagittal reference plane in PA cephalometry, we considered five kinds of midsagittal planes from which the distances to five landmarks were measured and compared the result with that of 3D CT. The midsagittal plane for 3D CT was determined by the landmarks Nasion, Sella and Basion. Results: PA measurements using the midsagittal reference plane on a perpendicular plane lying through the midpoint of the right and left latero-orbitales was closest to those of 3D CT. Conclusions: It was considered that latero-orbitale perpendicular could be used as the helpful midsagittal reference plane to assess facial asymmetry in PA cephalometry.

전기도금을 이용한 교정용 선재의 직경 증가에 관한 실험적 연구

조진형,김경근,황현식 전남대학교 치과대학 2001 구강과학 Vol.13 No.2

The purpose of this study was to evaluate the possibile clinical application of electroplating to increase diameter of an orthodontic wire, through examining the change of physical properties. The diameter of stainless steel orthodontic wire was increased from 0.016 inch to 0.018 inch by electroplating in a bath of nickel sulfate 100g/L, nickel chloride 60g/L, boric acid 30g/L, and sodium chloride 50g/L, under the conditions of 1.7V, 25∼29℃, and 3.1∼3.3pH. During the electroplating, the rate of diameter increase was measured every minute. To investigate uniformity, the diameter was measured at three different locations of each wire specimen after electroplating. An X-ray diffraction test was performed to analyze the nature of the electroplated metal. Following heat treatment to improve adhesion between the wire and electroplated metal, a three­point bending test was conducted to compare stiffness, yield strength, and ultimate strength among four wire groups; 0.016 inch, electroplated 016, electroplated and heat ­ treated 016, and 0.018 inch wires. Through the comparison of each wire group, following results were obtained. 1. In the lad ­ deflection graph, the curve of the eletoplated group was placed between that of the 0.016 inch group and the 0.018 inch group, and the curve closer to the 0.018 inch group by heat treatment. 2. In the electroplated and heat ­ treated 016 wire group, the values of stiffness, yield strength and ultimate strength showed higher tendency than in the original 0.016 inch group. Stiffness and ultimate strength showed statistically significant differences between two groups. 3. Stiffness, yield strength, and ultimate strength of electroplated wire presented lower values than those of 0.018 inch wire group. 4. stiffness, yield strength, and ultimate strength of electroplated and heat ­ treated wire showed higher tendency than those of electroplated wire group, and ultimate strength showed statistically significant difference between two groups. 5. After electroplating, the difference in diameter between the three locations was withing 0.1´0.3% variation, and showed no statistical significance.

전개하는 보의 종진동 해석

조은형,정진태 漢陽大學校 工學技術硏究所 2000 工學技術論文集 Vol.9 No.1

본 논문에서는 Hamilton의 원리를 이용하여 전개하는 보에 대한 지배방정식과 경계조건을유도한다. 유도된 지배방정식은 순간고유형상의 시간의존 기저함수를 이용한 Galerkin 방법으로 이산화한다. 본 논문에서는 이산화된 방정식을 가지고 보가 전개할 때와 후퇴할 때의 시간응답해석을 수행하며 이를 통해 시간에 따라 길이가 변하는 보의 종진동에 대한 전형적인 양상을 제시한다. In this paper, the governing equation and the boundary conditions of deploying beam are derived using Hamiltons principle. The Galerkin method with time-dependent basis functions of the instantaneous natural modes is adopted to discretize the governing equation. Based on the discretized equations, the time integration analysis is performed and numerical results for the deploying and retrieving velocity are analyzed to illustrate the qualitative features of longitudinal vibrations.

Ⅱ급 부정교합에서 혀, 설골의 위치 및 기도 크기에 관한 연구

조진형,김상철 원광대학교 생체재료·매식연구소 1999 원광생체재료·매식 Vol.8 No.1

The purpose of this study was to evaluate the position of tongue and hyoid bone and the dimension of airway in class Ⅱ malocclusion. Lateral cephalogram(63 patients : 33 in male, 30 in female, average age 23.2 years) taken in natural head position(NHP), were traced and measured about the head posture, the position of the tongue and the hyoid bone and the dimension of airway, using the horizontal and vertical reference lines The angle of mandibular plane to SN plane was employed to classify samples into groups of hypodivergent and hyperdivergent. Craniofacial measurements were compard between hypodivergent group and hyperdivergent group The results were as follows; 1. The craniocervical angle was smaller in the hypodivergent group than in the hyperdivergent group. 2. The dimension of nasopharyngeal airway was smaller in the hyperdivergent group than the hypodivergent group. But the dimension of oropharyngeal airway was of no significant difference. 3. Tongue position was lower in the hyperdivergent group than in the hypodivergent group. 4. The vertical or horizontal position of hyoid bone was not distinctly different between the hypodivergent group and the hyperdivergent group.

불소도포가 상아질 접착에 미치는 영향

조규증,권형조,박진훈 大韓齒科保存學會 1995 Restorative Dentistry & Endodontics Vol.20 No.1

AbstractThe purpose of this study was to investigate the effect of stannous fluoride on the dentin bonding with three kinds of commercially available dentin bonding systems containing diffe- rent adhesive monomers. Dentin specimens with exposed labial dentin prepared from freshly extracted bovine mandibular anterior teeth were divided into experimental and control groups. The specimens of experimental groups were bonded with dentin bonding systems and composite resins including All bond 2 & Bisfil, Scotchbond Multi-Purpose & Z100, and Denthesive II & Charisma after 2% stannous fluorided application for 5 minutes and washing for 1 minute. The specimens of control groups were bonded with the same dentin bonding systems and composite resins as used in the experimental groups. After bonded specimens were stored in 37? distilled water for 24 hours, the tensile bond strength and cohesive failure rate were measured, and then the pretreated dentin surfaces and the fractured dentin surfaces were examined under scanning electron microscope.The results were as follows :Mean bond strength of stannous fluoride applied groups of All bond 2, Scotchbond MP, and Denthesive II were 2.5MPa, l.lMPa, and l.lMPa respectively, and those of control groups were 7.5MPa, 8.1MPa, and 4.6MPa. Bond strength values of stannous fluoride applied groups were significantly lower than those of the control groups(pOn SEM observation of the fractured dentin-r'esin interface, while most of the specimens of stannous fluoride applied groups showed adhesive failure mode, those of All bond 2 and Scotchbond MP control groups showed mainly adhesive-cohesive mixed failure mode, and mainly adhesive failure mode in Denthesive II control group.

전기도금을 이용한 스테인레스 스틸 선재의 직경 증가에 관한 실험적 연구

조진형,성영은,이기헌,황현식 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

본 연구는 전기도금을 이용하여 교정용 선재의 직경을 증가시킨 후 그 물성 변화를 알아봄으로써 이의 임상적 적용 가능성을 알아보고자 시행되었다. 0.016 인치 스테인레스 스틸 교정용 선재에 전기도금을 위한 적절한 전처리를 시행한 후, 황상 니켈 100g/L, 염화니켈 60g/L, 붕산 30g/L, 염화나트륨 50g/L의 조성을 가지는 전해액을 제조하여 1.7V의 전압과 25∼29℃의 온도 3.1∼3.3pH의 조건 하에서 직경을 0.002 인치 증가시켜 0.018 인치 직경의 선재로 만들었다. 전기도금 과정 중 1분 단위로 직경을 측정하여 시간에 따른 직경 증가율을 구하였고, 도금 후 서로 다른 세 지점의 직경을 계측하여 균일성을 평가하였으며, 도금 금속의 정성분석을 위하여 X-선 회절감사를 시행하였다. 도금층의 밀착성 증진을 위해 400℃의 전기로에서 10분간 열처리를 시행한 후 도금 전후와 열처리 전후의 물성 변화를 알아보기 위하여 3점 굴곡 실험을 시행하여 다음과 같은 결과를 얻었다. 1. 전반적인 하중-변형을 곡선을 보면 0.016 인치 군과 0.018 인치 군 사이에 도금 처리한 군이 존재하였으며 열처리한 경우가 0.018 인치 군에 더욱 가까워지는 양상을 보였다. 2. 도금에 의해 직경은 0.002 인치 증가시킨 군이 기존의 0.016 인치 군에 비하여 강성과 항복상도, 극한강도 모두 증가하는 경향을 보였으며 이 중 강성과 극한 강도는 통계적인 유의한 차이를 보였다. 3. 0.016 인치에서 도금에 의해 직경을 0.002 인치 증가시킨 준이 기존의 0.018 인치 군보다 강성과 항복강도 극한강도 모두에서 낮게 나타났으며 통계적 유의차를 보았다. 4. 도금 후 열처리를 시행한 군이 시행하지 않은 군보다 강성, 항복강도, 극한강도 모두 높은 경향을 보였으며, 극한강도에서 유의한 차이를 나타내었다. 5. 전기도금 후 서로 다른 세 지점의 직경차이는 0.1∼0.3%로 균일하게 나타났으며 통계적으로도 유의차가 존재하지 않았다. The purpose of this study was to evaluate the possibile clinical application of electroplating to increase diameter of an orthodontic wire, through examining the change of physical properties. The diameter of stainless steel orthodontic wire was increased from 0.016 inch to 0.018 inch by electroplating in a bath of nickel sulfate 100g/L, nickel chloride 60g/L, boric acid 30g/L, and sodium chloride 50g/L, under the conditions of 1.7V, 25∼29℃, and 3.1∼3.3pH. During the electroplating, the rate of diameter increase was measured every minute. To investigate uniformity, the diameter was performed to analyze the nature of the electroplated metal. Following heat treatment to improve adhesion between the wire and electroplated metal, a three-point bending test was conducted to compare stiffness, yield strength, and ultimate strength among four wire groups; 0.016 inch, electroplated 016, electroplated and heat-treated 016, and 0.018 inch wires. Through the comparison of each wire group, following results were obtained. 1. In the load-deflection graph, the curve of the electroplated group was places between that of the 0.016 inch group and the 0.018 inch group, and the curve was closer to the 0.018 inch group by heat treatment. 2. In the electroplated and heat-treated 016 wire group, the values of stiffness, yield strength and ultimate strength showed higher tendency than in the original 0.016 inch group. Stiffness and ultimate strength showed statistically significant differences between two groups. 3. Stiffness, yield strength, and ultimate strength of electroplated wire presented lower values than those of 0.018 inch wire group. 4. Stiffness, yield strength, and ultimate strength of electroplated and heat-treated wire showed higher tendency than those of electroplated wire group, and ultimate strength showed statistically significant difference between two groups. 5. After electroplating, the difference in diameter between the three locations was within 0.1∼0.3% variation, and showed no statistical significance.

중추성 요붕증이 동반된 랑게르한스 세포 조직구증 1예

김진호,문준성,문선중,이지은,최재원,은미정,천경아,조인호,윤지성,원규장,이경희 신덕섭,이형우 영남대학교 의과대학 2005 Yeungnam University Journal of Medicine Vol.22 No.2

Central diabetes insipidus (DI) is a syndrome characterized by thirst, polydipsia and polyuria. Langerhans cell histiocytosis is one of the etiologies of DI. Recently we experienced a central DI associated with Langerhans cell histiocytosis. The 44 years old female patient complained right hip pain polydipsia and polyuria. We carried out water deprivation test. After vasopressin injection, urine osmotic pressure was increased form 109mOsmol/Kg to 327mOsmol/Kg (300%). Brain MRI showed a thickened pituitary stalk and at hot bone CT.CT guided biopsy revealed abnormal histiocytes proliferation and abundant lymphocytes, The final diagnosis was central DI associated with systemic Langerhans cell histiocytosis invading hip bone, L-spine and pituitary stalk. Desmopressin and etoposide chemotherapy were performed to the patient.

불안정성 흉요추체 방출형 골절 환자에서 기구를 이용한 고정술의 결과

안병조,이정청,김재은,김형일,김철진,최하영 대한신경외과학회 1996 Journal of Korean neurosurgical society Vol.25 No.9

Fifty six patients with unstable thoracolumbar bursting fractures were treated using variable internal fixation devices such as the Kaneda Anterior Fixation System(Kaneda device), the Z-Plate-ATL^(TM) Anterior Fixation System(Z-Plate ATL^(TM)device), the Harrington device. Cotrel-Dudousset(CD) or Compact Cotrel Dubousset(CCD) device of Steffee Transpedicular System with or without decompression. Suchy internal fixation devices were grouped into anterior and posterior internal fixation devices and compared with each other in the aspect of the degree of neurological improvement, the changes of the vertebral height and the kyphotic angle, the duration of admission, and postoperative complications. In conclusion, the anterior internal fixation device appears to be of more benefit in the management of patients with unstable thoracolumbar bursting fracture

전기분해에 의한 염색폐수의 탈색에 관한 연구

이진휘,이진희,연만형,조성국 서울産業大學校 1997 논문집 Vol.46 No.1

전기분해에 의한 염색폐수의 탈색효과를 규명하기 위하여 Fe, Al 및 Cu극판을 단일 또는 혼용하여 적색, 황색 및 청색산성염료 200ppm에 대하여 탈색실험을 수행한 결과 Fe(+)와 Al(-)전극을 혼용하고, 극간거리가 1.5㎝일 때 가장 제거율이 좋았다. 염색폐수의 농도 50∼250ppm에 대하여 전해질로써 NaCl을 0.1∼0.5% 사용하고 전류밀도 0.033∼0.166A/㎠로 실험한 결과 6분이상의 시간 경과후 95%이상 색도가 제거되었고, 전해질의 농도가 높을수록 소비전력은 높아지고 제거율은 향상되었으나 시간이 지남에 따라서 전력소비는 거의 일정하였다. This experiment is performed to investigate the decoloration of dye wastewater by using the same or different electrodes of Fe, Al and Cu. The waste solution consists of a single colored acidic dye of red, yellow or blue with a concentration of 200ppm. The results showed that the combination of Fe(+) and Al(-) electrodes and a distanced of 1.5㎝s between the electrodes was best for the decoloration process. It showed more than 95% decoloration occurred after 6 min. when we used NaCl solution of 0.1∼0.5% for electrolysis and current densities of 0.033∼0.166A/㎠ with solutions of 50∼250ppm. The higher the concentration of electrolyte, the higher the consumption of power becomes constant after a period of time.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.