• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.369-379
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• 2001

The aim of this study was to investigate the periodontal response according to the timing of orthodontic force application after bone graft into the angular bony defect. Nine dogs were divided into three groups, 2, 4, and 6 weeks, according to the timing of orthodontic force application after bone graft. Periodontal angular bony defects were created surgically at the distal aspect of both maxillary third incisors. Two weeks later, flap operation was performed to eliminate inflammation and reference notch was made on the root surface at the level of the bottom of each defect. Demineralized freeze-dried bone was implanted on the left side whereas only debridement was done on the other side. Experimental tooth movement was executed during 8 weeks on both graft and non-graft sides. After 2 weeks of retention period, animals were sacrificed for histologic specimens. The results were obtained as follows 1 New bone formation was more pronounced in the graft side than in the non-grad side in all experimental animals. 2. In the 6-week group, new bone and cementum formation was observed in more than half from the notch to the cemento-enamel junction, and the zone of connective tissue attachment was found without apical migration of junctional epithelium. 3. In the 4-week group, the amount of new bone formation was smaller than in the 6-week group whereas the overall remodeling pattern was similar. 4. New bone formation was confined to around the notch and the junctional epithelium migrated apically to the level of the notch with no connective tissue attachment and cementum formation in the 2-week group. The results of the present study suggest that periodontal response may be influenced by the timing of orthodontic force application after bone graft into angular bony defect.

• The korean journal of orthodontics
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• v.26 no.1 s.54
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• pp.17-32
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• 1996

It is important to understand the operating mechanism and force system of fixed appliance that most effective for individual tooth movement in various orthodontic appliances. The archwire system of fixed appliance is devided into 3 types, which is continuous arch, segmented arch and sectional arch. The last two types have longer interbracket distance and simple force operating points, so it is easy to control force system by operator. But the continuous arch has shorter interbracket distance and various bracket geometry, so it is hard to control and anaylze the force system. The purpose of this study was three dimentional force and moment analysis of continuous arch system by finite element method, which is similar situation to three dimentional elastic beam in structural engineering. Several sample form of various bracket geometry and artificial lower crowding typodont made by author were constructed, analyzed and compared each other. The results were as follows : 1. The force magnitude is linear proportional to the degree of displacement or tilting of the bracket. 2. The force magnitude is inversely non-linear proportional to the interbracket distance. 3. In three dimensional typodont model, while the force can be compared with that of the sample form in the area where adjacent bracket geometry is simple, the force is much more than the expected value in the area where adjacent bracket geometry is complex.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.46-53
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• 2002

Background: Pulmonary aspergilloma is relatively common in korea. It arises from the colonization and proliferation of Aspergillus in preexisting lung parenchymal cavities, in particular tuberculosis. The most common symptom in this disorder is hemoptysis, which mayor may not be massive and life threatening. A routine chest radiography and computed tomography (CT) are the most important diagnostic procedures. A surgical resection of the aspergilloma has recently been recommended, because of the relatively low incidence of postoperative complications than in the past. A more concentrated sample of patients with aspergilloma, who either underwent a thoracotomy or tested positive for aspergillus antibodies, were reviewed. Method : The medical records of twenty-two patients with aspergilloma, who had a proven thoracotomy (9 cases), or who tested positive for the diagnostic procedure and/or aspergillus antibodies (13 cases) from January 1995 to December 2000, were reviewed retrospectively. Results : The most common underlying lung disease was a current or old healed tuberculosis, and 3 patients had cultures of mycobacterium other than tuberculosis (MOTT). The mean time until the aspergilloma was detected 5.91 years in the healed tuberculosis cases. The others cases involved a lung abscess, bronchiectasis and without lung disease. The extrapulmonary disease was alcoholism and diabetes. Hemoptysis was most common in 72.7%. A computed tomography (CT) is useful for diagnosis. The right upper lobe, especially the posterior segment, is the most common location. Bronchial artery embolization is ineffective for a long term follow-up. A lobectomy is most common in a thoracotomy, and intra-operative and post-operative complications are rare. During follow-up, the mortality rate, not from the aspergilloma but from respiratory failure, was 13.6%. Conclusion : Aspergilloma is a common cavitary lung disease, It mainly arises from tuberculosis, either current or healed, but extra-pulmonary disease including alcoholism or diabetes are other possible risk factors. Their most common problem in aspergilloma is hemoptysis. Surgery has a low risk of post-operative complications and is recommended in relatively preserved lung function or healthy patients. Medical maneuvers including embolization, and the local insertion of certain materials needs to be studied more closely.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.237-243
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• 2008

Purpose: Postoperative Infectious complications are recognized as major complications that are associated with surgery. Although many studies have focused on the risk factors of postoperative complications, little is known about the risk factors of infectious complications after gastric cancer surgery, and especially after elective gastrectomy. There is now more and more interest in the risk factors of infectious complications in relation to controlling infection and as indicators of qualitatively assessing infectious complications. The aim of this study was to evaluate the risk factors related with infectious complications after performing elective gastrectomy for treating gastric cancer. Materials and Methods: We retrospectively reviewed a total of 788 patients who had undergone elective gastrectomy for gastric cancer between Jan. 2000 and Dec. 2007. The characteristics of the patients were divided according to the patients' factors and the operations' factors. Results: The patients' mean age was 58.9 (range: 24~91) years; 545 were male and 243 were female. The mean duration of the hospital stay was 20.3 days (range: 5~135 days), the mean operation time was 181.3 minutes (range: 65~440 minutes). The total complication rate was 17.1% (n=135) and the complication rate was 38.5% (n=52) among the 135 patients with infectious complications. The infectious complications were surgical site infection (59.7%), Pneumonia (19.3%), intra-abdominal abscess (11.5%), pseudomembranous colitis (5.7%), bacteremia (1.9%) and hepatic abscess (1.9%). On the univariate analysis, the significant risk factors were male gender, blood transfusion, smoking at the time of diagnosis, alcohol drinking, diabetes mellitus and previous cardiovascular disease (P<0.05 for all). On multivariate analysis that used a logistic regression model, the significant independent risk factors were smoking at the time of diagnosis (OR: 2.877. 95% CI: 1.449~5.713), blood transfusion (OR: 3.440, 95% CI: 1.241~9.534), diabetes mellitus (OR: 3.150, 95% CI: 1.518~6.538), and previous cardiovascular disease (OR: 2.784, 95% CI: 1.4731~5.2539). Conclusion: Pre- or post-operative blood transfusion and the patient's medical history such as previous cardiovascular disease, diabetes mellitus, smoking etc. are the risk factors for infectious complications after undergoing elective gastrectomy for gastric cancer. The patients that have these risk factors need to be treated with great care to prevent infectious disease after elective gastrectomy.

• Clinical and Experimental Pediatrics
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• v.45 no.8
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• pp.1007-1015
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• 2002

Purpose : The aim of this study is to find a method to diagnose and treat children who showed benign hemophagocytic histiocytes in bone marrow examination. Methods : We analyzed the clinical data of thirty patients retrospectively who showed benign hemophagocytic histiocytes in bone marrow examination from January 1995 to November 2001 at Keimyung University Dong-san Hospital. Bone marrow histiocytes were classified into a few, some, and many according to the number of histiocytes comparing with the white cells. Results : The age of thirty patients ranged from two months to 15 years. The median age was 5.6 years with male predominance(2.3 : 1). The most frequent clinical manifestation was fever; others were respiratory symptom, hepatosplenomegaly, lymphadenopathy and skin rash(in order of frequency). Common laboratory findings were leukopenia, thrombocytopenia, anemia and abnormal liver function test. Infection was present in 30 patients; causative organisms were documented in 15 patients, and bacterial infection was more common. Epstein Barr virus was the cause of infection in four patients. Bone marrow examination showed a few(20.0%), some(75.0%) and many(30.0%) hemophagocytic histiocytes. Combination immunochemotherapy including immunoglobulin, steroids and cyclosporine were helpful in 22 out of 30 patients. The mortality rate was high in young patients who showed some to many hemophagocytic histiocytes. Conclusion : Bone marrow examinations and early detection of histiocytes will be helpful in children who have fever, hepatosplenomegaly and abnormal liver function test. Immunochemotherapy were helpful and further investigation will be needed for the detection of the relationship between the bone marrow findings and prognosis.

• Tuberculosis and Respiratory Diseases
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• v.52 no.2
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• pp.107-116
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• 2002

Background: Matrix metalloproteinases(MMP) are essential enzymes for tumor invasion and metastasis. Among the MMP family, elevated MMP-9 and stromelysin-3(STR-3) expression have been reported to be poor prognostic factors in lung cancer patients. To evaluate the possibility of a molecular diagnosis of lung cancer using peripheral blood, the mRNA expression level of MMP-9 and STR-3 was measured using a reverse transcriptase-polymerase chain reaction (RT-PCR) in patients with lung cancer. Methods : Ninety six patients(44 patients with lung cancer, 19 pulmonary infection, and 33 control) were included. To detect MMP-9 and STR-3 mRNA expression, RT-PCR was performed in peripheral blood mononuclear cells. ELISA was also used to measure the serum level of MMP-9. Results : MMP-9 was expressed more frequently in patients with a pulmonary infection(18/19, 94.7%) compared to lung cancer patients(26/44, 59.1%) or the controls (23/33, 69.7%) (p=0.018). On the other hand, STR-3 expression was observed more frequently in patients with lung cancer(37/44, 84.1%) compared to the lung infection patients(8/19, 42.1%) or control(20/33, 60.6%) (p=0.003). Among the lung cancer patients, MMP-9 was expressed more frequently when a tumor invaded the lymph nodes(17/24, 70.8%) compared to when a tumor did not(3/13, 23.1%) (p=0.005). The MMP-9 and STR-3 expression levels had no relationship with age, sex, tumor size, distant metastasis, or tumor histology. The serum MMP-9 concentration was not higher in lung cancer patients compared to patients with a pulmonary infection or the control subjects. Conclusion : STR-3 may be used as a diagnostic marker in the peripheral blood of lung cancer patients using RT-PCR. Further studies to evaluate the clinical significance of elevated STR-3 expression in lung cancer patients is recommended.

• Tuberculosis and Respiratory Diseases
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• v.49 no.5
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• pp.624-632
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• 2000

Background : Home ventilation can decrease hospital-acquired infection, increase physical activity, improve nutritional status, enhance quality of life, and reduce medical costs. The number of patient using home ventilators has been increasing, particularly in Europe and United States. Although the number of patients with home ventilation has been increasing in Korea, the current status of these patients is not well known. This study was undertaken to obtain basic information upon these patients in addition to evaluating any problems related to patients' home care in our country. Methods : A register of 92 patients with home ventilators in Seoul and Kyunggi Province were obtained from commercial ventilator supply companies. The patients were contacted by phone and 29 of them accepted our visit. Information concerning education about home care before discharge, equipment cost, and problems related to home care were documented. The mode and preset variables of the home ventilator were checked; tidal volume (TV), peak airway pressure, and oxygen saturation were measured. Results : There were 26 males (90%) and their mean age was 48.0 (${\pm}20.1$) years. The underlying diseases were : 21 neuromuscular disorders, 2 spinal cord injuries, 6 chronic lung diseases. Among the caregivers, spouses (n=14) predominated. Education for home care before discharge was performed primarily by intensive care unit nurses and the education for ventilator management by commercial companies. Twenty-five of the 29 patients had tracheostomies. Volume targeted type (VTT ; n=20, 69%) was more frequently used than the pressure targeted type (PTT). Twenty-three of the 29 patients purchased a ventilator privately, which cost 7,450,000 (${\pm}$3,290,000) won for a PTT, and 14,280.000 (${\pm}$3,130,000) won for a VTT. Total cost for the equipment was 11,430,000 (${\pm}$634,000) won. The average cost required for home care per month was 1,120,000 (${\pm}$1,360, 000) won. Conclusion : The commonest underlying disease of the patients was neuromuscular disease. The VTT ventilator was primarily used with tracheostomy. Patients and their families considered the financial difficulties associated with purchasing and maintaining equipment for home care an urgent problem. Some patients were aided by a visiting nurse, however most patients were neglected and left without professional medical supervision.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.855-864
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• 1998

The purposes of this study were to evaluate the cephalometric characteristics of Korean female patients with Class II division 2 malocclusion and to compare Korean females with Caucasian females who had same type of malocclusion. All of the samples had Class II division 2 malocclusion with deep overbite (more than 4mm) and full permanent dentition. These samples were divided into two groups according to the races: Group 1(N=16; Korean females; average age=18Y 2M) and Group 2 (N:20; Caucasian females; average age=14Y 2M). The pretreatment lateral cephalograms were measured, analyzed and compared by using 38 variables and independent t-test. And the results were as follows: 1. Although there were no differences in Overbite, SN to mandibular plane angle, Palatomandibular plane angle, and FMA between Group 1 and 2, the other vertical relation variables of maxilla and mandible (SN to palatal plane angle, SN to occlusal plane angle, ODI) of Group 1 showed more clockwise rotation tendency of occlusal plane and less hypodivergency tendency than those of Group 2. 2. There were no differences in mandibular body length and ramus height between Group 1 and 2 except small upper genial angle of Group 1. There was less counterclockwise rotation tendency of mandible in Group 1. 3. There were no statistical significant differences in UAFH/LAFH and PFH/AFH between Group 1 and 2. 4. Although there were no differences of overjet and anteroposterior position of mandible between Group 1 and 2, the position of maxilla of Group 1 was more retropositioned than that of Group 2. 5. Except the more protrusion of lower incisor to A-Pog of Group 1, there were no differences of inclination and distance of upper and lower incisors to basal plane between Group 1 and 2. 6. The distance from upper- first molar to palatal plane showed no difference between Group 1 and 2. But the distance from lower first molar to mandibular plane of Group 1 was greater than that of Group 2. So it may be partially related to the clockwise rotation of occlusal plane and the less counterclockwise rotation tendency of mandible of Group 1. 7. Group 1 had more protrusive upper and lower lips than Group 2.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.145-149
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• 2010

Purpose: Recently, $^{18}F$-FDG Fusion PET which has a high sensitivity for diagnosing cancer is being used for purpose of health examination. This study is to demonstrate that $^{18}F$-FDG fusion PET study is useful for diagnosing an early stage cancer. Materials and Methods: This research has been conducted with 2790 patients visited Seoul National University Hospital Healthcare System (SNUHHS) for $^{18}F$-FDG fusion PET study for a health examination from February, 2004 to December 2008. PET/CT images were acquired from skull base to femur after 1 hour from injecting $^{18}F$-FDG 0.14 mCi/kg to the patients. GEMINI GS (Philips, Netherlands) was used for scanning. Results: From February 2004 to December 2008, $^{18}F$-FDG Fusion PET study was performed for 99,009 patients among all patients who visited SNUHHS and 2,790 patients was performed. Diagnostic rate for malignant cancer was 0.95% for the patients who were not examined by $^{18}F$-FDG Fusion PET study. 1.94% was for the patients who were. The rate of malignant tumor was showed 10% and benign tumor was 90% among 542 patients who showed abnormality in the PET/CT images. Types and rates of malignant tumor showed thyroid cancer: 31.5%, lung cancer: 14.8%, stomach cancer: 9.3%, rectum cancer: 3.7%, breast cancer: 3.7%, metastasis cancer: 16.7%. Nonspecific lymph node in the mediastinum, physiologic uptake in the colon, diffuse mild hypermetabolism in bilateral thyroid gland were shown as a benign tumor. Conclusion: The diagnostic rate of malignant tumor with $^{18}F$-FDG Fusion PET for a purpose of health examination was relatively higher than general medical examination. Consequently, it is superior and useful for applying $^{18}F$-FDG Fusion PET study for health examination.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.149-156
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• 2005

Purpose : Acute septic arthritis and acute osteomyelitis are not rare diseases in pediatric population. But when the diagnosis is delayed or inappropriate treatments are given, permanent disabilities of joint or bone can be followed. We analysed clinical manifestations, laboratory findings, X-ray findings, causative microorganisms and antibiotic susceptibility results of the two diseases in children. Methods : During January 1992 and May 2002, we conducted a retrospective study of 103 children who were diagnosed as acute septic arthritis and acute osteomyelitis. We selected out 34 children who had positive culture results in the blood or involved sites. Results : 19 cases were diagnosed as acute septic arthritis and 15 cases were acute osteomyelitis. These diseases were most common in preschool children and next in neonates. Hip joints and tibia were the most common sites in each disease. X-ray findings showed abnormalities in 6 cases(36%) of acute septic arthritis and 7 cases(50%) of acute osteomyelitis on admission. The most common microorganism isolated from the involved sites was Staphylococcus aureus; 12 out of 14 cases in acute septic arthritis and 6 out of 13 cases in acute osteomyelitis. Conclusion : It is difficult to make a clear initial diagnosis of the two diseases. We could not find any differences between these two diseases on clinical manifestations such as fever, swelling, tenderness and limitation of movements in joint and bone. The most common microorganism was Staphylococcus aureus.