구순구개열환자에서 자가입자망상골을 이용한 이차성 치조골이식에 관한 임상적 연구

김종렬,진성준,조영철,표세정,변준호 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.2

Purpose : This study is conducted to evaluate the clinical success of secondary alveolar bone grafting using autogenous iliac particulate cancellous bone marrow in cleft maxilla. Materials and methods : We evaluated 107 cleft patients who had been admitted to the Dept. of Oral and Maxillofacial Surgery of Pusan National University Hospital from January 1, 1991 to January 31, 1999 and had been performed secondary alveola bone grafting with autogenous particulated cancellous bone marrow from iliac crest. Results : 1. Men were 70 and women were 37, which shows 65.4% and 34.6% and the proportion of males to females was 1.9: 1. Unilateral cases were 89(83.2%) and bilateral cases were 18(16.8%). 2, Age of bone grafting is widely distributed from 7 to 29, and the average was 13.2. 3. Success rate was 97.8% in unilateral cases, 94.4% in bilateral cases. Overall success rate was 96.7%. 4. We evaluated the bone graft contour by the percentage of bone attachment level adjacent to the alveolar cleft and the menial side showed 82.4% and the distal 87.7%. 5. The amount of notching the alveolar ridge at the grafted site through the ratio of notching length up to the most apical base to the length of proximal segment anatomic root was 0.19.

구순구개열환자에서 자기늑골을 이용한 일차성 골이식

김종렬,정기돈,진성준,조영철,변준호,손우성 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.5

Alveolar bone grafting is an essential component of successful surgical rehabilitation in many common cleft deformities. Primary alveolar bone grafting is defined as alveolar bone grafting which takes place before eruption of the primary dentition or before 1 years of age. The major objective in primary alveolar bone grafting is to prevent significant maxillary segmental collapse and arch disturbances. If severe, this can make secondary rehabilitation difficult, costly, and protracted. Such early stabilization may eliminate or, at least, decrease the amount of orthodontic arch expansion required during the transitional dentition period. Furthermore, early obliteration of alveolus fistulae improves speech and dental hygiene. It is critical that abutting maxillary segmental alignment be achieved(generally when the patient is 8 to 10 months of age) before grafting. Otherwise, the amount of dissection necessary to develop mucosal flaps for bone graft coverage will be more extensive, thus risking increased scar formation with potential adverse effects on growth. We report a preliminary result of 4 cases of primary alveolar bone graft using rib bone, performed by limited dissection and onlay graft technique at 8 to 10 months of age. They showed satisfactory clinical results especially in terms of growth up to now.

코발트 실리사이드에 의한 기공 형성에 대한 연구

김종채,김영철 한국기술교육대학교 2000 論文集 Vol.7 No.1

ABSTRACT Void formation at sidewall spacer edge of MOSFETs has been investigated as a function of dopant species. Voids were not formed with NM+NP and PM+PP LDD (lightly doped drain) structures, but with NM+PP LDD structure. Phosphorous dopant is known to retard cobalt silicidation at elevated temperature. Therefore, instead of high tensile stress at the spacer edge and large amount of silicon vacancies, retarded cobalt silicidation due to dopant species is proposed as a void formation mechanism at the sidewall spacer of MOSFETs. Key words: void formation (기공 형성), cobalt silicidation (코발트 실리콘 반응), dopant (미량 첨가 원소), LDD (미량 도핑된 드레인)

화상 환자에서 발생한 외과적 중재술을 요하는 감염성 심내막염 2예

김근숙,이태유,정연손,최창순,최민호,류제헌,김철홍,조구영,우흥정 대한감염학회 2003 감염과 화학요법 Vol.35 No.3

감염성 심내막염은 화상 후에 발생할 수 있는 치명적인 합병증이다. 임상 증상은 일반적으로 없는 경우가 대부분이고 지속되는 발열과 양성 혈액 배양 검사가 유일하다. 감염의 다른 확실한 원인 없이 발열과 양성 혈액 배양 검사가 있을 때는 감염성 심내막염을 강력하게 의심해야 하며 심장 초음파로 진단 가능하다. 감염성 심내막염은 사망률은 높지만 초기에 진단하면 항생제 정주를 지속하는 것으로 치료할 수 있다. 저자들은 화상환자에서 발생한 수술적 처치를 필요로 하는 감염성 심내막염 2예를 경험하였기에 보고하는 바이다. Infective endocarditis is a rare but fatal complication following burn injury. The clinical presentation is silent, but with persistent fever and positive blood culture. The manipulation of clinical care as well as the burn wound itself and immunosuppression caused by extensive bums puts the burn patients at risk of bacteremia. Staphylococcus aureus and Gram-negative bacilli are most common pathogens of infective endocarditis following burns. We report herein two cases of infective endocarditis in the burn patients who requires surgical intervention. The first case was caused by Pseudomonas aeruginosa with complication of multifocal pneumonia, and the second case by coagulase-negative stapylococcus with cerebral hemorrhage.

生長錐에 의한 편백나무 直徑生長의 豫測에 關한 硏究

金是璟,權泳徹 진주산업대학교 1977 論文集 Vol.15 No.-

This study is carried out to investigate the prediction of the growth of diameter by the increment borer in hinoki cypress with an accurate formula. The data of this study are the data of 40 from the core in position of breast height of 20 pieces of hinoky cypress using the increment borer. The results are summarized as follows. 1. Let Y be the growth of semi-diameter for 5 years of the past from a certain moment, X be the growth of semi-diameter for 5 years before Y, and Z be the growth of semi-diameter for 5 years of the future from the moment, then we can obtain the following formula by the method of least squares using the data of 40 above mentioned, Z ㎝=0.1534+0.6754 Y ㎝…………(1) 2. As there is no rationality for current annual increment of trees between the formula(1) regarding as Y=O is Z=0.1534, therefore we can obtain the next formula using the method of least squares by formula of logarithm. log Z=0.0547+0.8816 log Y…………(2) 3. The prediction of the growth of diameter for comming 5 years (Z) regarding as equivalent to the growth of past 5 years (Y) is not correct. Using the data we can obtain the next formula, Y ㎝=0.0023+0.8041 X ㎝…………(3) and, as there is no significant difference between the formula (1) and (3), we can substitute (3) in place of (1). 4. We can easily obtain the formula (3) by measuring X and Y in the stand under investigation, and we can predict Z by Y of the formula (1) substituting Y by X of the formula (3) with no bias, accordingly it is good example to apply to the formula (2) with Y of the formula (3).

SD Rats를 이용 1-hexene의 흡입독성 연구

김현영,임철홍,정용현,이권섭,이성배,이준연,한정희,전윤석,이용묵 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

The purpose of this study was to investigate the acute (4 hours) and repeated-dose (6 hours a day, 5 days a week, 4 weeks) toxic effects of I -hexene on Sprague- Dawley (SD) rats which were treated by inhalation. The results were as follows; I. The median lethal concentration (LC_(50)) was estimated 52,694 ppm (confidence limit 95%; 49,494~55,447 ppm) in acute inhalation. Abnormal clinical signs related to the l-Hexene were not observed with the acute inhalation dose. Gross findings of necropsy revealed on evidence of specific toxicity related to the 1-hexene, II. By repeated inhalation exposure the body weight of male were more or less reduced by the dose of 2,500 ppm and 5,000 ppm compared with control group. However there were no significant variation hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-hexene were not shown. In conclusion when we exposed I-hexene to SD rats for 4 weeks, 5 days per week, 6 hours per day, the Lowest observed effect level (LOEL) was over 2,500 ppm and Non observed effect level (NOEL) was below 500 ppm.

교정용 선재와 브라켓 사이의 마찰력에 관한 연구

김철위,박영준,이용근 大韓齒科器材學會 1995 대한치과재료학회지 Vol.22 No.2

Mechanical friction makes the orthodontic tooth movement require greater force than the biological tooth movement. Friction is affected by the size, shape, and material of both the bracket and the wire. This study was designed to investigate the effect of material or size of orthodontic brackets and orthodontic wires on the amount of frictional forces generated during simulated tooth movement. A testing apparatus was designed to simulate the clinical situation in which the center of resistance of a tooth is not on the same plane as that of bracket, thereby resulting in some tipping of the bracket slot relative to orthodontic wire (100 gram weight was suspended). In angulated and non-angulated experimental condition, the orthodontic wires were drawn through the testing apparatus with the speed of 2mm/minute. The results were as follows : 1. In both of the cases of the metal bracket and ceramic bracket, the frictional forces were greater in angulated experimental group than non-angulated group. In both of the non-angulated and angulated experimental group, the frictional forces of ceramic brackets were greater than those of metal brackets. In most of cases, these differences were statistically significant(p<0.05) with a few exceptions. 2. In general, the frictional forces of orthodontic wires with circular cross-cut surface were lower than those wires with rectangular cross-cut surfaces. But there was no statistically significant correlation between the size of orthodontic wire and frictional forces. 3. There was no difference between the frictional of the stainless-steel orthodontic wires and those of the cobalt-chromium orthodontic wires, but the frictional forces varied depending on the measuring condition or brand of the wires. 4. The frictional forces of β-titanium orthodontic wires were significantly higher than those of stainless-steel orthodontic wires were cobalt-chromium orthodontic wires.

크롬(Ⅵ)의 체내 흡수와 소실속도에 관한 연구

김현영,이성배,임철홍,이권섭,정용현,이종성,한정희,전윤석,황호순,이용묵 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.1

The CrO3 mostly used in plating. metal surface disposal, leather, cosmetic manufacturing, as an experiment material by repeatedly inhaling and exposure the male S.D. rats at a 0.00, 0.2., 0.50, 1.25 mg/㎡ concentration(particle size: 0.5-0.5 aerosol)6hours a day, 5day a week in 13weeks comparing with 2weeks, 8weeks of recovery group about the noxiousness of the experiment animal and the reduce scale of the CrO3 in the internal organ especially in blook and respiratory organ with the period of convalescent and clearance. The experiment results which we received are as follows. 1. In blood the RBC, HGB and HCT experiment, rats with 0.20, 0.50 mg/㎡ concentration showed that there were some decreases but not dependent. The kidneys absolute weight compared with control group was reduced intentionally(p〈0.05) and the lungs absolute weight compared with control group showed intentional increase(p〉0.05). 2. After the exposure of the experiment material, the whole blook, l\blood plasma and red blood cell in blood by (x): the period of convalescent, per (y); the decreasing of Cr concentration, was y=66.51 e -0.057x, y=67.2 e-0.101x, y=70.01 e-0.030 in 0.50 mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life (day)was estimated 12.0, 6086, 23.0 each. 3, After the exposure of the experiment material, the experiment animals lung, liver and kidneys by(x); the period of convalescent, per (y); the decreasing of Cr conentration, was y=1808 e-0.00493x, y=12.02e-0.0297x, y=67.61 e-0.0292x in 0.50mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life(day)was estimated 140.6, 23.3, 23.7, each, and including lung, liver with all of the experiment internal organs, the Cr clearance decreased as the exposure concentration increased.

S.D. Rats를 이용 1, 1-Dichloro-1-fluoroethane의 아민성 흡입독성 연구

김현영,이성배,임철홍,김철우,점용현,한정희,전윤석,최수영,강대봉,이용묵 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.1

There were no specific effects for test materials on Sprague-Dawley (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body l, l-Dichloro-1 -fluoroethane (used as coolant, metal cleaner and solvents) exposure(0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations, there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration. Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-l -fluoroethene inhalation was evaluated in groups with 3,000 ppm below (S .D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-l-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure .

치과 자석 어태치먼트 재료에 적용을 위한 이온질화된 Ti 첨가 스테인리스강의 표면특성

김성일,최한철,고영무 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.1

Dental magnetic attachment have been applied to removable prosthetic appliances, maxillofacial prostheses, obturator and dental implant but they still have some problems such as low corrosion resistance in oral environments. To increase the corrosion resistance of dental magnetic materials. Nd-Fe-B materials were sealed with stainless steel, but pitting corrosion, intergranular corrosion and erosion corrosion occurred predominantly at welded zone and center of magnetic attachment in corrosive environment and mechanical wear condition. In order to develop corrosion resistance of magnetic materials, the surface modification of stainless steel for magnetic attachment sealing materials were investigated by utilizing potentiostat. It was found that plasma nitriding at 380℃, compared with 500℃, produced a good corrosion resistance as nitriding time increased, whereas stainless steel containing low Ti content showed that pitting potential and corrosion potential decreased.