• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.493-501
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• 2002

This study evaluated the microleakage performance of four self-etcing primer adhesives(Clearfil SE Bond, Clearfil Liner Bond 2, UniFil Bond, and FL Bond) and one self-etching adhesive(Prompt L-Pop). Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on both buccal and lingual surfaces of 50 extracted human molar teeth. Prepared teeth were randomly divided into five groups and restored using one of five adhesives and composite resins: Prompt L-Pop/Filtek Z 250(Group 1), Clearfil SE Bond/Clearfil AP-X(Group 2), Clearfil Liner Bond 2/Clearfil AP-X(Group 3), UniFil Bond/UniFil F(Group 4), and FL Bond/Filtek Z 250(Group 5). Following one day storage in room temperature water, the restored teeth were thermocycled for 500 cycles between 5$^{\circ}C$ and 55$^{\circ}C$. Marginal microleakage was assessed by dye penetration using 2% methylene blue dye. After 24 hours, the teeth were sectioned longitudinally and evaluated for microleakage under steromicroscope The data were statistically analysed by Kruskal-Wallis Test, Mann-Whitney and Wilcoxon signed ranked tests. The results of this study were as follows ; 1. The microleakges at both enamel and dentinal mal$.$gins were the lowest in group 4. increasing among groups in the following order: group 2, follwed by group 5, follwed by group 1, and the highest in group 3. 2. At the enamel margins, the microleakage of group 3 was significantly higher than those of groups 2. 4 and 5(p<0.05), and also the microleakage of group 1 was statistically higher than those of groups 2 and 5(p<0.05). 3. At the dentinal margins, microleakage of group 3 was signincantly higher than microleakages of groups 1, 2, 4 and 5(p<0.05). 4. Compared with microleakages between the enamel and dentinal margins of each group, groups 1, 4 and 5 at enamel margin and group 2 and group 3 at dentinal margin were higher microleakage. But there was no significant difference between enamel and dentinal microleakages of each group(p>0.05).

• Journal of Mechanical Science and Technology
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• v.16 no.7
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• pp.1009-1018
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• 2002

The Representative Interactive Flamelet (RIF) concept has been applied to numerically simulate the combustion processes and pollutant formation in the direct injection diesel engine. Due to the ability for interactively describing the transient behaviors of local flame structures with CFD solver, the RIF concept has the capabilities to predict the auto-ignition and subsequent flame propagation in the diesel engine combustion chamber as well as to effectively account for the detailed mechanisms of soot formation, NOx formation including thermal NO path, prompt and nitrous 70x formation, and reburning process. Special emphasis is given to the turbulent combustion model which properly accounts for vaporization effects on the mixture fraction fluctuations and the pdf model. The results of numerical modeling using the RIF concept are compared with experimental data and with numerical results of the commonly applied procedure which the low-temperature and high-temperature oxidation processes are represented by the Shell ignition model and the eddy dissipation model, respectively. Numerical results indicate that the RIF approach including the vaporization effect on turbulent spray combustion process successfully predicts the ignition delay time and location as well as the pollutant formation.

• Restorative Dentistry and Endodontics
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• v.31 no.4
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• pp.263-268
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• 2006

Recently, self-etching adhesive system has been introduced to simplify the clinical bonding proce- dures. It is less acidic compared to the phosphoric acid, thus there is doubt whether this system has enough bond strength to enamel. The purpose of this study was to investigate the influence of additional etching on the adhesion of resin composite to enamel. Ninety extracted bovine permanent anterior teeth were used. The labial surfaces of the crown were ground with 600-grit abrasive paper under wet condition. The teeth were randomly divided into six groups of 15 teeth each. Clearfil SE $Bond^{\circledR},\;Adper^{TM}$ Prompt L-Pop and Tyrian $SPE^{TM}$ were used as self-etching primers. Each self-etching primers were applied in both enamel specimens with and without additional etching. For additional etching groups, enamel surface was pretreated with 32% phosphoric acid (UNI-ETCH, Bisco, Inc., Schaumburg, IL. USA). Hybrid resin composite Clearfil AP-X, (Kuraray Co., Ltd., Osaka, Japan) was packed into the mold and light-cured for 40 seconds. Twenty-four hours after storage, the specimens were tested in shear bond strength. The data for each group were subjected to independent t - test at p < 0.01 to make comparisons among the groups. In Clearfil SE $Bond^{\circledR}$, shear bond strength of additional etching group was higher than no additional etching group (p < 0.01). In $Adper^{TM}$ Prompt L-Pop and Tyrian SPE, there were no significant difference between additional etching and non-etching groups (p > 0.01). In conclusion, self-etching adhesive system with weak acid seems to have higher bond strength to enamel with additional etching, while self-etching adhesive system with strong acid seems not.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5759-5762
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• 2012

The objective of the study was to evaluate the efficacy of a health check-up program among Thai people at the National Cancer Institute in the years 2008-2009. The program included history taking, physical examination, chest X-ray, EKG, and laboratory tests. A total of 28,240 women and 9,665 men were included in the study, with mean ages of 44.5 and 46.9 years, respectively. The study showed that obesity, as assessed by a BMI over 25.0 kg/m2, in men and women was present in 41.4% and 30%, respectively. Biochemical study revealed that anemia was prevalent in 21.6% of men and 20.1% of women. High plasma glucose level (>115 mg/dL), cholesterol level (>200 mg/dL), triglyceride level (>190 mg/dL) in men was 13.8%, 63.8%, 22.6% and 7.7%, 61.1%, 8.9% in women. Hepatitis B virus infection was found 7.5% in men and 4.1% in women. In this study, 177 new cancer cases were detected, of which 35 were breast, 19 were cervical and 26 were colorectal, most of these cancers being detected at early stage. In addition, precancerous states was also found including 718 cases of benign and 99 cases of adenoma in situ. In conclusion, an annual check up may detect abnormalities that have no obvious clinical symptoms of disease. Early detection of asymptomatic neoplasms and precursor lesions should contribute to a prompt provision of treatment and further decline of death from cancer.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.241-245
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• 2009

Traumatic diaphragmatic rupture is uncommon, but requires a prompt diagnosis and repair. Diaphragmatic injury is most commonly associated with automobile accidents. The diagnosis is difficult and may be delayed because there are no specific symptoms, signs, or radiographic studies that are pathognomic for diaphragmatic injury. The most important factor in the diagnosis is a high suspicion and the use of proper diagnostic studies. We report a case involving the delayed presentation of diaphragmatic rupture in a 54 year old man, requiring surgical repair 12 days following multiple blunt trauma. It should be noted that early recognition for diaphragmatic injury is important in patients with multiple trauma to avoid the potential fatal complications.

• Journal of Trauma and Injury
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• v.29 no.4
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• pp.204-208
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• 2016

For an orthopaedic surgeon, the critical decisions to either amputate or salvage a limb with severe crushing injury with progressive ischemic change due to arterial rupture or occlusion can become a clinical dilemma at the Emergency Department (ED). And reperfusion injury is one of the fetal complications after vascular reconstruction. The authors present a case which was able to save patient's life by rapid vessel ligation at bedside to prevent severe reperfusion injury. A 43-year-old male patient with no pre-existing medical conditions was transported by helicopter to Level I trauma center from incident scene. Initial result of extended focused assessment with sonography for trauma (eFAST) was negative. The trauma series X-rays at the trauma bay of ED showed a multiple contiguous rib fractures with hemothorax and his pelvic radiograph revealed a complex pelvic trauma of an Anterior Posterior Compression (APC) Type II. Lower extremity computed tomography showed a discontinuity in common femoral artery at the fracture site and no distal run off. Surgical finding revealed a complete rupture of common femoral artery and vein around the fracture site. But due to the age aspect of the patient, the operating team decided a vascular repair rather than amputation even if the anticipated reperfusion time was 7 hours from the onset of trauma. Only two hours after the reperfusion, the patient was in a state of shock when his arterial blood gas analysis (ABGA) showed a drop of pH from 7.32 to 7.18. An imminent bedside procedure of aseptic opening the surgical site and clamping the anastomosis site was taken place rather than undergoing a surgery of amputation because of ultimately unstable vital sign. The authors would like to emphasize the importance of rapid decision making and prompt vessel ligation which supply blood flow to the ischemic limb to increase the survival rate in case of profound reperfusion injury.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.135-152
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• 1983

Emergency medical service is an important part of the health care delivery system, and the optimal allocation of resources and their efficient utilization are essentially demanded. Since these conditions are the prerequisite to prompt treatment which, in turn, will be crucial for life saving and in reducing the undesirable sequelae of the event. This study, taking the hyperbaric chamber for carbon monoxide poisoning as an example, is to develop a stochastic approach for solving the problems of optimal allocation of such emergency medical facility in Korea. The hyperbaric chamber, in Korea, is used almost exclusively for the treatment of acute carbon monoxide poisoning, most of which occur at home, since the coal briquette is used as domestic fuel by 69.6 per cent of the Korean population. The annual incidence rate of the comatous and fatal carbon monoxide poisoning is estimated at 45.5 per 10,000 of coal briquette-using population. It offers a serious public health problem and occupies a large portion of the emergency outpatients, especially in the winter season. The requirement of hyperbaric chambers can be calculated by setting the level of the annual queueing rate, which is here defined as the proportion of the annual number of the queued patients among the annual number of the total patients. The rate is determined by the size of the coal briquette-using population which generate a certain number of carbon monoxide poisoning patients in terms of the annual incidence rate, and the number of hyperbaric chambers per hospital to which the patients are sent, assuming that there is no referral of the patients among hospitals. The queueing occurs due to the conflicting events of the 'arrival' of the patients and the 'service' of the hyperbaric chambers. Here, we can assume that the length of the service time of hyperbaric chambers is fixed at sixty minutes, and the service discipline is based on 'first come, first served'. The arrival pattern of the carbon monoxide poisoning is relatively unique, because it usually occurs while the people are in bed. Diurnal variation of the carbon monoxide poisoning can hardly be formulated mathematically, so empirical cumulative distribution of the probability of the hourly arrival of the patients was used for Monte Carlo simulation to calculate the probability of queueing by the number of the patients per day, for the cases of one, two or three hyperbaric chambers assumed to be available per hospital. Incidence of the carbon monoxide poisoning also has strong seasonal variation, because of the four distinctive seasons in Korea. So the number of the patients per day could not be assumed to be distributed according to the Poisson distribution. Testing the fitness of various distributions of rare event, it turned out to be that the daily distribution of the carbon monoxide poisoning fits well to the Polya-Eggenberger distribution. With this model, we could forecast the number of the poisonings per day by the size of the coal-briquette using population. By combining the probability of queueing by the number of patients per day, and the probability of the number of patients per day in a year, we can estimate the number of the queued patients and the number of the patients in a year by the number of hyperbaric chamber per hospital and by the size of coal briquette-using population. Setting 5 per cent as the annual queueing rate, the required number of hyperbaric chambers was calculated for each province and for the whole country, in the cases of 25, 50, 75 and 100 per cent of the treatment rate which stand for the rate of the patients treated by hyperbaric chamber among the patients who are to be treated. Findings of the study were as follows. 1. Probability of the number of patients per day follows Polya-Eggenberger distribution. $$P(X=\gamma)=\frac{\Pi\limits_{k=1}^\gamma[m+(K-1)\times10.86]}{\gamma!}\times11.86^{-{(\frac{m}{10.86}+\gamma)}}$$ when$${\gamma}=1,2,...,n$$$$P(X=0)=11.86^{-(m/10.86)}$$ when $${\gamma}=0$$ Hourly arrival pattern of the patients turned out to be bimodal, the large peak was observed in $7 : 00{\sim}8 : 00$ a.m., and the small peak in $11 : 00{\sim}12 : 00$ p.m. 2. In the cases of only one or two hyperbaric chambers installed per hospital, the annual queueing rate will be at the level of more than 5 per cent. Only in case of three chambers, however, the rate will reach 5 per cent when the average number of the patients per day is 0.481. 3. According to the results above, a hospital equipped with three hyperbaric chambers will be able to serve 166,485, 83,242, 55,495 and 41,620 of population, when the treatmet rate are 25, 50, 75 and 100 per cent. 4. The required number of hyperbaric chambers are estimated at 483, 963, 1,441 and 1,923 when the treatment rate are taken as 25, 50, 75 and 100 per cent. Therefore, the shortage are respectively turned out to be 312, 791. 1,270 and 1,752. The author believes that the methodology developed in this study will also be applicable to the problems of resource allocation for the other kinds of the emergency medical facilities.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.106-116
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• 2001

Background : Pulmonary thromboembolism is relatively frequent and potentially fatal. However, it is commonly misdiagnosed. The incidence of pulmonary thromboembolism is not decreasing despite advances in diagnosis and effective prophylatic measures. Its potential for significant sequela necessitates a prompt diagnosis and treatment. Unfortunately, there are many difficulties and problems regarding accurate diagnosis. There is a low prevalence of deep vein thrombosis and pulmonary thromboembolism in Korea and only few reports on this subject are available. Method : The clinical features of 36 patients, who were diagnosed with pulmonary thromboembolism at the Korea University medical center, were reviewed. Results : 1) There was no significant difference in prevalence between men an women, and the mean age was 50.9 years in men 59.2 years in women. 2) The frequent causes of pulmonary thromboembolism were malignancies (22.2%), surgery (22.2%), and heart disease(8.2%). Specific causes were not identified in 33.3%. 3) The most common symptom was dyspnea(72.2%), and the most common sign was tachypnea(61.1%). 4) The EKG findings were normal in 28.6%, an S1Q3T3 pulmonale pattern in 25.7%, ST or QRS changes in others. 5) The chest X-ray findings indicated pulmonary infiltration in 37.5%, cardiomegaly in 15.6%, pleural effusion in 12.5%, and normal in 27.8%. The perfusion lung scan showed a high probability in 66.7%, and intermediate or low probability in 33.3%. 6) The pulmonary arterial pressure(PAP) in the high probability groups was 57.9mmHg with a higher mortality rate(35%). Conclusion : Pulmonary thromboembolism is not uncommon in Korea and its clinical features do not differ greatly from thase reported in the literature. When pulmonary thromboemblism of unknown causes are diagnosed, a search for an occult malignancy is recommended. Rapid diagnosis and treatment are achieved when thromboemblism is suspected.

• Pediatric Infection and Vaccine
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• v.4 no.2
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• pp.210-217
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• 1997

Purpose: To prevent residual physical disability and chronic infection, prompt diagnosis and adequate treatment are important in the skeletal infections in children. Although radioisotope scanning is knwon as the method of choice for early diagnosis of bone infection, we conducted a study on twenty nine children who had skeletal infections to reevaluate the most appropriate way in diagnosis and management. Methods: A retrospective study was conducted on twenty nine children, who were admitted to the departments of Pediatrics and Orthopedic Surgery and who had acute osteomyelitis or septic arthritis, through review of medical records, radiologic & radioisotope study results. Their diagnoses were confirmed by bacteriologic cultures on the aspirated specimens from suspected bony lesions. Results: 1) Among twenty nine patients, there were 6 infants including 5 newborn infants, and 23 children were aged between 1 and 15 years. Male to female ratio was 1.4 to 1. 2) Point tenderness was noted in all cases, and the common physical signs were swelling, limitation of motion, fever and local heat in the order of frequency. 3) Fifty two percents of the patients were diagnosed within a week after onset of symptoms and all cases were within 15 days. 4) Leukocytosis was noted in only 58.6% of cases but erythrocyte sedimentation rate was increased in all cases except only one case. Staphylococcus aureus was revealed as the most common etiologic agent. 5) Radioisotope scans showed hot uptake in five of six cases(83.3%) who had no abnormal finding on plain skeletal radiolograms. Conclusions: Although radioisotope scan and MRI are helpful in early diagnosis before radiologic finding was detected on plain X-ray film, the antimicrobial therapy can be started after bacteriologic study of the aspirated specimens from the suspected skeletal lesions if skeletal infection is highly suspected clinically.