FET형 반도체 마이크로센서 개발(Ⅱ)

손병기,이흥락,박이순,조진호,이성필,최평,서화일,고성택,박재윤,서장수,김창수 경북대학교 센서기술연구소 1994 연차보고서 Vol.1994 No.-

현재 의료진단, 화학공정의 모니터링이나 환경공학적 감시 및 제어 등의 분야에서 사용되고 있는 기존의 센서는 고가이며 용적이 클 뿐만 아니라 분석시간이 길고 사용하기 까다로운 것 등 여러 가지 문제점이 있다. 또한 측정환경에 영향을 주지 않을 만큼 충분히 작으며 빠른 분석시간을 가진 센서를 필요로 하고 있다. 본 연구에서는 기존의 센서들의 난점을 극복할 수 있는 새로운 형태의 FET형 전해질(electrolyte : H^+, K^+, Ca^2+, Na^+)분석 시스템, 용존가스(O_2, CO_2)분석 시스템의 개발을 중점적으로 추진하며, FET형 압력센서, 습도센서, 방사형 온도센서 등의 개별 FET형 센서에 관한 연구도 병행하고자 한다. Recently various kinds of sensors have been developed, being applicated to their own purpose. There are lots of difficulties to apply them to measurements in which the real-time monitoring is required without disturbing the surrounding environment. FET type semiconductor sensors, fabricated by the semiconductor integration technologies, have many advantages for their miniaturization, standardization, mass-production and in vivo/in situ monitoring. They also hold a very proper configuration for multi-functional sensors or integrated smart sensors, and wide availability by forming various kinds of physical or chemical sensing materials onto their sensing gates.

斷續方式靜電測定器의 製作

孫炳基,文在德 경북대학교 교육대학원 1974 논문집 Vol.5 No.-

An equipment for static-electricity measurements was constructed by employing the chopping system. Its structure has been explained and its performance characteristics investigated. It was sensitive and much more capable by using with a cathode-ray oscilloscope. An equivalent circuit for the constructed equipment has also been analyzed, and the equivalent analysis was in good agreement with the experimental results.

지단백과 알부민 및 이들의 변형물질이 메산지움세포 증식에 미치는 영향

손일석,이태원,박재경,김희진,조병수,임천규,김명재 대한신장학회 2002 Kidney Research and Clinical Practice Vol.21 No.2

목 적 : 혈청 지단백과 알부민은 그 자체로써 또는 산화나 당화 과정에 의한 변형을 거쳐 사구체 질환을 진행시킬 수 있는 것으로 알려져 있다. 그 기전은 분명하지는 않으나 메산지움세포 증식과 관련이 있는 것으로 알려져 있다. 저자들은 비교적 간단한 흡광도측정법을 이용하여 지단백과 알부민 및 그들의 변형물질들이 각각 메산지움세포 증식에 미치는 영향을 알아보고자 하였다. 방 법: 정상인의 혈청 지단백을 원심분리 하여 저밀도지단백, 고밀도지단백, 초저밀도지단백을얻고, 산화 저밀도지단백, 당화 저밀도지단백, 그리고 혈청 알부민과 당화 알부민을 각각 농도를 달리하여 배양 중인 인간 메산지움세포에 가한 후 흡광도를 측정함으로써 메산지움세포의 증식정도를 알아보았다. 양성 대조군으로 interleukin-1β를 이용하였다. 결 과: 저밀도지단백은 농도 증가시 50 μg/mL와 100 μg/mL에서 세포의 증식을 보였으며,고밀도지단백과 초저밀도지단백은 농도에 따른 유의한 변화가 없었다. 산화 저밀도지단백은5 μg/mL에서부터 세포의 증식을 초래한 후 10 μg/mL와 25 μg/mL에서도 이를 유지하였다. 당화 저밀도지단백은 농도 증가에 따라 10 μg/mL와 100 μg/mL에서 세포의 증식을 억제하였다. 알부민은 농도 500 μg/mL에서 세포 증식을 억제하다가 고농도(1,000 μg/mL)에서는 영향이 없었으며, 당화 알부민 역시 100 μg/mL의 적은 농도에서는 억제효과를 보였으나 고농도(1,000 μg/mL)에서는 오히려 증식을 일으키는 결과를 보였다. 결 론: 저농도에서 저밀도지단백과 산화 저밀도지단백은 사람 메산지움세포의 증식을 초래하였으며, 당화 저밀도지단백은 증식을 억제하였다. 알부민은 일정농도까지 사람 메산지움세포의 증식을 억제하다가 고농도에서는 영향이 없었으며, 당화 알부민도 일정농도까지 증식 억제 효과가 있다가 고농도에서는 오히려 증식을 초래하는 양상을 보였다. Background : Modified lipoproteins may be involved in nephro- and glomerulosclerosis. Diabetic nephropathy-like lesions have also been induced in a rat model by glycated and glycoxidized albumin. In cultured rat or human mesangial cells, enhanced cell proliferation and production of mesangial matrix in response to lipoproteins and their modified forms have been demonstrated by [3H]-thymidine incorporation and cell counting assays. But these methods are relatively complex and most of them have used only one or two of the lipoprotein, albumin and their modified forms. Methods : We investigated the effects of native and modifed lipoproteins, and albumin on cultured human mesangial cell proliferation using non-radioactive colorimetric method by MTS/PMS assay. Lipoproteins added were low density lipoprotein(LDL), high density lipoprotein(HDL), very low density lipoprotein(VLDL), oxidized LDL(oxidation with copper sulfate in vitro) and glycated LDL and we also used albumin, glycated albumin, and interleukin-1β as a positive control. Results : Interleukin-1β promoted the proliferation of cultured human mesangial cells up to concentration 20 ng/mL. LDL induced the proliferation of mesangial cells in a concentration-dependent manner up to concentration 100 μg/mL. HDL and VLDL had no significant proliferative effect. Oxidized LDL caused the proliferation of mesangial cells at low concentration up to concentration 25 μg/mL. Addition of glycated LDL resulted in a concentrationdependent inhibition of mesangial cells. Albumin and glycated albumin inhibited the proliferation of mesangial cells at low concentration of 100 μg/mL, but cell growth was increased at higher concentrations. Conclusion : We demonstrated the effects of the single and modified proteins on the proliferation of cultured human mesangial cell by relatively simple colorimetric method. Results were almostly identical to those of previous studies obtained by radioactive method or cell counting assay. (Korean J Nephrol 2002;21(2):266-275)

高分子固體誘電物質과 水銀의 接觸帶電

孫炳基,文在德 慶北大學校 産業開發硏究所 1975 硏究報告 Vol.3 No.-

Contact-electrifications of some dielectrics(lucite, PVC, and bakelite) with mercury have been investigated. It has been observed that the contact-electrified charges on dielectrics are saturated as the contact-time duration with mercury increases, and that the values of saturation-charges and these saturation time-constants decrease linearly with the humidity of atmospheric gas. The saturation time-constant of lucite, measured in air of 26℃, 1 atm and the relative humidity of 12%, was 86 seconds, and decreasing rate of charge density on lucite for the humidity was 7.5×10 exp (-8) coul/㎡·%. The contact-electrification characteristics of the lucite in nitrogen gas is similar to that in air. But increasing of the contact-time duration, the PVC is initially electrified in the negative polarity and then its polarity has been reversed. And the absolute values of generated charges for both the lucite and PVC samples in nitrogen gas are smaller than those in air, presumably, due to the effect of oxygen. These experimental results generally support the electronic theory for the contact-electrification of high-polymer dielectrics.

구진상괴사성 결핵진 3례

손보성,송준영,정재봉,김병천,이상숙,류영욱,이규석 啓明大學校 醫科大學 1994 계명의대학술지 Vol.13 No.4

Papulonecrotic tuberculid is an eruption of necrotizing papules, particularly affecting the extremities and occurring in more or less symmetrical crops, and responding to antituberculosis therapy. Individual lesions heal with scarring. Histologically, vascular involvement is seen in early lesions. Late lesions are divided into two forms. In superficial forms, wedge shaped area of necrosis forms in epidermis and upper dermis. Epithelial and lymphoid cells gather around its periphery. In deep forms, with no epidermal change, granulomatous changes surrounded by well defined palisading histiocyte and lymphoid, epithelioid cells are seen. In mid-dermis and perivascular area, vessel shows vasculitis. In the first case, leukocytoclastic vasculitis and early granuloma formation were seen. In the second case, palisading granuloma formation was seen. In the third case, tuberculoid granuloma formation was seen. We report three cases of papulonecrotic tuberculid showing three different stages of histological finding, in individual cases.

FET형 반도체 마이크로센서 개발(Ⅲ)

손병기,이흥락,박이순,조진호,이성필,최평,서화일,박재윤,송경은,김창수 경북대학교 센서기술연구소 1995 연차보고서 Vol.1995 No.-

현재 의료진단, 화학공정의 모니터링이나 환경공학적 감시 및 제어 등의 분야에서 사용되고 있는 기존의 센서는 고가이며 용적이 클 뿐만 아니라 분석시간이 길고 사용하기 까다로운 것 등 여러 가지 문제점이 있다. 또한 측정환경에 영향을 주지 않을 만큼 충분히 작으며 빠른 분석시간을 가진 센서를 필요로 하고 있다. 본 연구에서는 기존의 센서들의 난점을 극복할 수 있는 새로운 형태의 FET형 전해질(electrolyte : H^+, K^+, Ca^2+, Na^+)센서소자 및 분석 시스템, 용존가스(O_2, CO_2)센서의 개발을 중점적으로 추진하였으며, FET형 압력센서, 습도센서 둥의 개별 FET형 센서에 관한 기초연구도 병행하였다. The conventional sensors have many problems such as high cost, large dimension, long analysis time and troublesome handling to apply to the fields of medical diagnosis, monitoring of chemical process and environmental monitoring/control. The main objects of this research are to develope a new FET type electrolyte(H^+, K^+, Ca^2+, Na^+)sensors, analysis system, and dissoved gas(O_2, CO_2)senors that can overcome the problems of the conventional sensors, and parallel basic researches on FET. type sensors such as pressure and humidity are also in progress.

정신분열증 유형 및 경과 변화에 따른 혈청면역글로부린 변화

손인기,이재광,박두병 大韓神經精神醫學會 1995 신경정신의학 Vol.34 No.4

Objects : IN this study the authors tried to elucidate any relationship between schizophrenia and the immune function by measuring the serum immunoglobulin level in schizophrenic patients and observing the changes of the serum immunoglobulin in the clinical course and type. Methods : The subjects of this study were 28 schizophrenics who had been admitted to the Neuropsychiatric Department of Chung Ang University Hospital and a private neuropsychiatry clinic and 20 healthy young adults were recruited for control. On admission and after one month later, the serum immunoglobulin concentration and PANSS were serially evaluated. The collected data were analysed through the SPSS program. Applied statistic methods were Mann-Whitney U test, Kreuskal-Wallis test and Pearson's correlation. Results : 1) Only Ig A concentration of schizophrenic patients was significantly higher than that of normal controls. 2) There was no significant difference between positive and negative schizophrenic patients, but both positive and negative schizophrenic patients showed a significantly higher concentration of Ig A than controls. 3) Age was positively correlated with Ig A concentration in schizophrenic patients. 4) Each Ig concentration of schizophrenics tended to decline on the clinical course, but it was not statistically significant. 5) In schizophrenic patients, each Ig concentration at admission was not related to degree of improvement of psychotic symptoms and dosage of antipsychotic medication had no influence on each Ig concentration. Consluion : In summary, it was postulated that immune system abnormality contributed to pathology of schizophrenia. But immune system abnormalities might be due to altered stress response in schizophrenia. Therefore further research for relationship of stress-schizophrenia-immune system is needed to support these interpretations. also between positive and negative schizophrenia, immune function or stress response showed no difference.

Nd: YAG 레이저 조사가 Clacium Fluoride 형성 및 치아 내산성에 미치는 영향

최병재,김성오,손흥규,이제호,박광균 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.2

불소도포시 주로 형성되는 calcium fluoride는 구강내 환경에서 pH에 의해 조절되는 불소의 저장고 역할을 하여 치아우식 예방에 있어서 중요한 역할을 하는 것으로 알려져 있다. 따라서 불소도포의 우식예방 효과는 calcium fluoride를 얼마나 많이 형성시켜 오래 지속시키는 가에 달려있다. 이에 치아 내산성 증가에 효과 있다고 알려진 Nd:YAG 레이저 조사가 calcium fluoride형성 및 치아 내산성에 미치는 영향에 대해 알아보기 위해서 실험을 시행하였다. 소의 영구전치에서 276개의 시편을 제작하여 아무런 처치를 하지 않은 군을 대조군으로 하고 1.23% acidulated phosphate fluoride (APF) 5분, 30분 도포 및 Nd:YAG 레이저 조사에너지 밀도 20J/㎠,40J/㎠의 조건에 따라 불소 도포군, 레이저 조사군, 불소 도포후 레이저 조사군, 레이저 조사후 불소 도포군으로 분류하였다. 불소도포를 시행한 경우 이를 다시 KOH 처리 여부에 따라 나누어 23개의 실험조건을 만들었다. 각 실험조건에 12개의 시편을 배정하고 이중 10개의 시편은 불소 및 무기인 측정에, 나머지 2개의 시편은 표면 관찰에 사용하였다. KOH 비처지군에서 0.1N HCIO4로 enamel biopsy를 시행하여 탈회 법랑질의 불소농도 및 탈회깊이를 측정하였으며, KOH 처치군에서는 1 M KOH로 24시간 처리하여 calcium fluoride를 정량 후 enamel biopsy를 시행하였다. 실험결과 얻어진 자료 및 주사 전자현미경 관찰 소견을 비교하여 다음의 결과를 얻었다. 1. KOH 비처치군에서 탈회된 법랑질의 불소농도는 레이저조사 후 불소도포시 레이저 에너지 밀도 증가에 따라 증가되는 경향을 보였다. 2. KOH 비처치군에서 법랑질 탈회깊이는 불소를 5분 도포후 레이저 20J/㎠를 조사한 경우를 제외하고는 레이저와 불소를 병행하여 처치시 각각을 단독으로 치치시보다 탈회깊이가 작았다 (p<0.05). 3. Calcium fluoride의 양은 레이저의 조사에 의해 유의 있게 증가하지 않았다 (p>0.05). 4. Calcium fluoride 입자는 불소만 도포한 경우에 비해 레이저 조사후 불소도포시 입자크기가 증가되었으며, 불소도포후 레이저 조사시 입자크기의 증가와 함께 일부 융합된 양상을 보였다. 5. KOH 처치군에서 법랑질의 불소농도는 불소를 30분 도포후 레이저를 조사한 경우를 제외하고는 대조군의 불소농도와 유의한 차이가 없었다(p>0.05). 6.KOH 처치군에서 불소와 레이저를 병행한 경우, 불소만 도포한 경우보다 탈횐된 법랑질의 깊이가 작았다 (p<0.05). 7. KOH 비처치군에서 탈회된 법랑질의 불소농도와 탈회깊이의 상관관계 (Spearman correlation coefficient: -0.6281)는 KOH 처치군 (Spearman correlation coefficient: -0.3792)에 비해 높은 음의 상관 관계를 보였고, 동일한 조건으로 불소도포 및 레이저 조사를 시행한 경우에 있어서 KOH 처리 여부에 따른 탈회법랑질 깊이의 유의차가 있는 경우 calcium fluoride의 형성량이 많았다. 이상의 실험결과로 미루어 보아 레이저 조사가 calcium fluoride의 형성량에 영향을 미치지 않았으나 레이저 조사의 영향으로 calcium fluoride의 용해가 감소하는 것으로 판단된다. 또한 불소도포 및 레이저 조사의 병행은 각각을 단독으로 처치한 경우에 비하여 치아 내산성 증가면에서 유리하므로 임상에서 불소도포주기 연장과 같은 유용한 결과를 얻을 수 있을 것으로 생각된다. Calcium fluoride. created by topical fluoride application, is the reservoir for fluoride ion regulated by pH in the oral environment. Therefore, the amount and the maintenance of calcium fluoride have an important role in preventing dental caries. The aim of this study is to evaluate the effect of Nd:YAG laser irradiaiton on the generation of calcium fluoride and the acid resistance of tooth enamel. The bovine anterior permanent teeth were prepared (n=276), and divided into following groups: no treatment(control), fluoride application alone, laser irradiation alone, laser irradiation after fluoride application, and fluoride application after laser irradiation. And each group was subdivided based on the application time of 1.23% acidulated phosphate fluoride (APF) (5 min and 30 min) and the irradiation energy of Nd:YAG laser (20J/㎠ and 40J/㎠). In case of fluoride application, each group was divided according to KOH treatment. Twenty three treatment conditions were made for this experiment and twelve specimens were assigned to each treatment condition. In each treatment condidtion, ten specimens were used for chemical analysis and two specimens were observed under SEM. In groups without treating KOH, fluoride content and the depth of enamel dissolved were measured using enamel biopsy technique. In groups with treating KOH, the amount of calcium fluoride was measured by the treatment with 1 M KOH for 24 hours and enamel biopsy was performed after KOH treatment. The results were analyzed by the fluoride content and the depth of enamel dissolved by enamel biopsy, amount and thickness of calcium fluoride, and the surface structures of enamel. The results are as follows: 1. In groups without treating KOH, the fluoride content of removed enamel showed a positive relationship with the energy density of laser when the laser irradiated before fluoride application. 2. In groups without treating KOH, the depth of enamel dissolved decreased more with the combined laser and fluoride treatment than with laser or fluoride treatment, except for the case of 20J/㎠ laser irradiation after 5 minute fluoride application (p<0.05). 3. The amount of calcium fluoride did not increased by laser treatment with no statistical significance(p>0.05). 4. The particle size of calcium fluoride increased in case of fluoride treatment after laser irradiation, compared with fluoride application alone. In case of laser treatment after fluoride application, the particle size of calcium fluoride increased and some of the particles fused as well. 5. There were no significant differences in the fluoride content of dissolved enamel between groups without treating KOH and control group, except for the case of laser irradiation after treatment of APF for 30 minutes (p>0.05). 6. In groups with treating KOH, depth of removed enamel in the groups of combined treatment with laser and fluoride was shallower than that in fluoride application groups (p<0.05). 7. In groups without treating KOH, the relationship between fluoride content and the depth of enamel dissolved showed more negative (Spearman correlation coefficient: -0.6281)than in groups with treating KOH (Spearman correlation coefficient: -0.3792). The greater amount of calcium fluoride could be found in case where there was a significant differences of the depth of enamel dissolved between groups with and without treating KOH. From these results, it can be concluded that laser seems to be a little effects on the amount of calcium fluoride formation, but has some effect on the lowering the solubility of calicium fluoride. As the combined treatment of laser and fluoride application showed more effective acid-resistant property, more extended recall period for fluoride application can be achieved with this combined treatment in the clinic.

서울 강서지역 1개 대학병원에서 성인 급성 신우신염의 원인균과 항생제 감수성

황병연,이재갑,박대원,이연주,김성범,엄중식,손장욱,정희진,김우주,김민자,박승철 대한감염학회 2003 감염과 화학요법 Vol.35 No.5

목적 : 3년간 서울시 강서지역의 1개 대학병원에서 입원치료를 받은 성인 급성 신우신염 환자를 대상으로 원인균과 항생제 감수성을 조사하고, 향후 급성 신우신염의 초기 경험적 치료 항생제를 제안하고자 하였다. 방법 : 1999년 1월부터 2001년 12월까지 3년간 고려대학교 의과대학 구로병원에 상부요로감염으로 내원한 16세 이상 환자 229명의 의무 기록을 검토를 통하여, 인구학적 특성, 원인균, 항생제 감수성, 초기 항생제 사용 양상과 입원기간을 조사하였다. 결과 : 연구에 포함된 229명을 118명의 단순 신우신염군과 111명의 복잡 신우신염군으로 구분 하였다. 단수 신우신염의 평균 발생 연령은 38.2세와 복잡 신우신염 56.1세로 복잡 신우신염 환자의 연령이 유의하게 높았다(P<0.001). 양군 모두에서 원인균 중 E. coli의 분리율이 가장 높았으며 항생제 감수성 결과 ampicillin, trimethoprim-sulfame-thoxazole에는 높은 내성률을 보였고, ciprofloxacin, gentamicin, cefotaxime에 대한 감수성은 비교적 높았으나 복잡 신우신염의 경우 단순 신우신염에 비하여 ciprofloxacin, gentamicin에 대한 감수성이 다소 낮은 것을 확인할 수 있었다. 평균 입원 기간, 항생제 투여 기간에 있어서도 복잡 신우신염군에서 유의하게 길었다. 결과 : 본 연구의 결과 서울의 강서 지역에서 대학병원급에 치료 의뢰되는 단순 급성 신우신염의 치료에 있어 1차 항생제로 3세대 cephalosporin, aminoglycoside, quinolone 중 한가지를 초기 경험적 치료제로 사용을 고려하여야 할 것으로 사료된다. Background : The purpose of this study is to recommend the initial therapeutic regimen for adult patients with acute pyelonephritis (APN) according to the changes of antimicrobial susceptibility patterns of causative microorganisms isolated from patients with APN. Methods : We reviewed medical charts of 229 APN patients, who had been treated at Korea University Guro Hospital from 1st of January. 1999 to 31st of December, 2001. We investigated the demographic data, clinical findings, durations of hospital treatment, antimicrobial susceptibility patterns of the causative microorganisms and initial antibiotic regimens in patients with APN. Results : In this study, 229 adult patients with APN were classified into simple APN patients (118 patients, 51.5%) and complicated APN patients (111 patients, 48.4%). Mean age of patients with simple APN was 38.2±14.1 years old and that of patients with complicated APN was 56.1±14.9 years old. Mean age of patients with complicated APN was significantly higher than that of simple APN patients (P<0.0001). Escherichia coli was the most common microorganism both in simple APN (96.7%) group and in complicated APN (90.6%) group. Antimicrobial susceptibility of E. coli was at the low level of ampicillin (31%/20%) and trimethoprim-sulfamethoxazole (42.6%/34.2%) in each group. In contrast, ciprofloxacin (11.5%/22.7%), gentamicin (16.4%/22%) and cefotaxime (0%/8.2%) resistance remained at relatively lower level. In comparison of simple APN with complicated APN, ciprofloxacin and gentamicin resistances were higher in complicted APN group. Average duration of hospitalization (5.9±2.3 days/8.2±4.6 days) and duration of antibiotic use (12.1±3.9 days/15.3±10.0 days) were significantly longer in complicated APN. Conclusions: The results of this study suggests that 3rd cephalosporin, aminoglycoside or quinolone antibiotic would considered as one of the initial therapeutic regimen for patients with simple APN in southwestern Seoul.

치아의 견인을 위한 버튼 접착시 오염이 인장강도에 미치는 영향

최병재,김성오,이제호,손흥규 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.2

We already know that it is very difficult to obtain an 'isolated field' for direct bonding during the surgical exposure of unerupted teeth. The aim of this in-vitro study is to simulate the clinical situation of forced eruption and to evaluate the tensile strengths of preligatured button with several types of contamination which can happen during the surgical exposure of unerupted teeth. Four orthodontic direct bonding systems were used. (Ortho-One, Rely-a-Bond, Ortho-Two, PhaseⅡ) Each material was divided into four groups(n=20) : Group 1. (Control, no contamination), Group 2. (Rinse etching agent with saline instead of water), Group 3. (Blood contamination of etched surface for 30 seconds), Group 4. (Blood contamination of primed surface for 30 seconds) 320 bovine anterior permanent teeth were divided into the above mentioned 16 groups. Enamel surface was flattened and ground under water coolant. Pre-ligatured buttons were prepared to the same form. (Cut 0.25 ligature wire 10 cm in length. Twist the ligature wire 30 times clockwise. Mark the wire 15mm and 35mm points from button. Make a loop sticking two points together and twist the loop 6 times counterclockwise.) The bonded specimens were stored at 37℃ saline solution for 3 days. then the tensile strength of each sample was measured with Instron universal testing machine, crosshead speed of 0.5mm/min. the following results were obtained : 1. As compared to control groups (Group 1) of each material, Rely-a-Bond had a significantly lower mean tensile strengths than other material. (p<0.01) 2. In Group 2. of Ortho-One and Rely-a-Bond, the mean tensile strengths decreased about 7.7% and 11.1%, respectively with statistical significances. (p<0.05) 3. In Group 2. of Ortho-Two and PhaseⅡ, the mean tensile strengths did not decrease. 4. In Group 3. of Ortho-One, Rely-a-Bond, Ortho-Two, and PhaseⅡ, the mean tensile strengths decreased about 60.8%, 56.1%, 60.2%, and 46.0%, respectively with statistical significances. (p<0.01) 5. In Group 4. of Ortho-One and Rely-a-Bond, the mean tensile strengths did not decrease. 6. In Group 4. of Ortho-Two and PhaseⅡ, the mean tensile strengths were decreased about 20.95% and 22.28%, respectively with statistical significances. (p<0.01) There were formations of a hump shaped mass from bonding resin under blood contamination which disturbed direct bonding procedure. According to Reynolds, the proper bond strength for clinical manipulation should be at least 45N or about 4.5Kg.F. According to these results, it can be concluded that Ortho-One could be used during surgical exposure of unerupted teeth. In any case, blood contamination of the etched surface should be avoided, but the blood contamination of primed surface of Ortho-One may not decrease bond strength. Just 'blowing-out' is enough to remove blood from primed surface of Ortho-One. You can verify the clean surface of the primer of Ortho-One after blowing out the blood contamination.