• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.18-26
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• 2021

Purpose: Generally, patients are noticed to store denture in water when removed from the mouth. However, few studies have reported the advantage of volumetric change in underwater storage over dry storage. To be a reference in defining the proper denture storage method, this study aims to evaluate the volumetric change and dimensional deformation in case of underwater and dry storage. Materials and methods: Definitive casts were scanned by a model scanner, and denture bases were designed with computer-aided design (CAD) software. Twelve denture bases (upper 6, lower 6) were printed with 3D printer. Printed denture bases were invested and flasked with heat-curing method. 6 upper and 6 lower dentures were divided into group A and B, and each group contains 3 upper and 3 lower dentures. Group A was stored dry at room temperature, group B was stored underwater. Group B was scanned at every 24 hours for 28 days and scanned data was saved as stereolithography (SLA) file. These SLA files were analyzed to measure the difference in volumetric change of a month and Kruskal-Wallis test were used for statistical analysis. Best-fit algorithm was used to overlap and 3-dimensional color-coded map was used to observe the changing pattern of impression surface. Results: No significant difference was found in volumetric changes regardless of the storage methods. In dry-stored denture base, significant changes were found in the palate of upper jaw and posterior lingual border of lower jaw in direction away from the underlying tissue, maxillary tuberosity of upper jaw and retromolar pad area of lower jaw in direction towards the underlying tissue. Conclusion: Storing the denture underwater shows less volumetric change of impression surface than storing in the dry air.

• Journal of the Korean Orthopaedic Association
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• v.55 no.5
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• pp.383-396
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• 2020

Purpose: This study compared the injury mechanism, site, type, initial management approach of orthopedic injury, and outcomes according to the injury severity in moderate-to-severe injured patients. Materials and Methods: During 57-month, excluding the period when the authors' emergency/trauma center was not operating, from 2014 to 2019, a retrospective study was conducted on 778 patients with orthopedic injuries among patients with an Injury Severity Score (ISS)>9 scored. The patients were classified into moderate-injured group (group-1, 679) and severe-injured group (group-2, 99) according to the injury severity based on the ISS and physiologic parameters. The injury mechanism and non-orthopedic injury were evaluated. Orthopedic injuries were assessed according to the injury pattern and the number of anatomical regions and bone sites involved. The management approach for the orthopedic injuries in two groups was compared. Outcomes (hospital stay, systemic complications, and in-hospital mortality) were evaluated, and the risk factors for mortality were analyzed. Results: In group-2, the incidence of younger males, high-energy mechanisms, and accompanying injuries was significantly higher than in group-1. The number of anatomical regions and bone sites involved increased in group-2. The involvement of the pelvis, spine, and upper extremity was significantly higher in group-2, whereas group-1 was involved mainly by the lower extremities. Depending on the patient's condition, definitive or staged management for orthopedic injuries may be used. Group-1 was treated mainly with definite fixation after the physiological stabilization process, and group-2 was treated with staged management using temporary external fixation. The hospital stay was significantly longer in group-2. The overall systematic complications and in-hospital mortality was approximately 4.9% and 4.5%. A higher injury severity was associated with higher in-hospital mortality (2.9%, 15.2%; p<0.0001). Increasing age and high ISS are independent risk factors for mortality. Conclusion: A higher severity of injury was associated with a higher incidence of high-energy mechanism, younger, male, accompanying injuries, and the frequency and severity of orthopedic injuries. Severe polytrauma patients were treated mainly with a staged approach, such as external fixation. The hospital stay, systematic complications, and in-hospital mortality were significantly higher in severe-injured patients. Age and ISS are strong predictors of in-hospital mortality in polytrauma.

• Journal of the Korean Burn Society
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• v.24 no.2
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• pp.21-29
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• 2021

Purpose: Frostbite is a hazard to people exposed to cold environments. With the progression of modern industrial development and change of leisure behavior encountering cold environments, frequent accidental exposure to frostbite injury during work and human behavior is increasing, and the predisposing factors of frostbite were greatly changed than before. The purpose of this study was to make epidemiological analysis, and to review the treatment outcomes of frostbite. Methods: From March 2010 to February 2021, this study has included 27 patients with second- to third-degree frostbite injuries in Advanced Burn Reconstruction Center, Bundang Jesaeng Hosptial. A retrospective study was made about the distribution of age, gender, predisposing factors, prevalent area, type of managements, and the length of treatment period. Results: In our institution, acute management of frostbite patients has included rewarming, anticoagulation therapy (acetylsalicylic acid), and agents to improve vascular perfusion (lipo-prostaglandin E1 [Eglandin^®]). The 25 frostbite patients with second-degree frostbite (92.6%) were successfully managed by the conservative treatment alone with a mean of 20.3 days healing time. Two patients with third-degree frostbite (7.4%) also showed good outcomes after surgical reconstruction with a mean of 59 days healing time. In our clinical experiences of third-degree frostbite, definitive surgical reconstruction should be recommended to wait for more than 4~6 weeks for identification of clear demarcation of necrotic tissue caused by frostbite. In this study, 43 frostbite injuries site in 27 frostbite patients occurred. Among them, 15 patients (55.6%) had multiple-site frostbite injury. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments (40.8%), misapplying ice pack for treatment purposes (7.4%), barefoot walking on the cold ground (3.7%), and loss of consciousness in cold grounds (3.7%). The most prevalent sites of frostbite injuries revealed as the hand (58.1%), followed by the foot (32.6%), face (7.0%), and abdomen (2.3%). And in the winter season from the November to March, the incidence rate of frostbite injuries was high at 74.1%. Conclusion: This study included 27 frostbite patients with 43 frostbite sites since last decade in a single institution at the community hospital. The frostbite patients with second-degree frostbite (92.6%) were successfully healed by the conservative treatment alone with a mean of 20.3 days healing time. The most common predisposing cause of frostbite was refrigerant gas accidents (44.4%), followed by outdoor activity in cold environments, etc. The most prevalent site of frostbite injuries was the hand (58.1%). And the most prevalent seasonal incidence of frostbite was from November to March (74.1%).

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.72-81
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• 2024

Purpose: This study aimed to assess the marginal and internal fit of 3-unit monolithic zirconia fixed partial dentures (FPDs) fabricated via computer-aided design and computer-aided manufacturing (CAD/CAM) from solid working casts and removable die system. Materials and Methods: The tooth preparation protocol for a zirconia crown was executed on the mandibular right first premolar and mandibular right first molar, with the creation of a reference cast featuring an absent mandibular right second premolar. The reference cast was duplicated using polyvinyl siloxane impression, from which 20 working casts were fabricated following typical dental laboratory procedures. For comparative analysis, 10 FPDs were produced from a removable die system (RD group) and the remaining 10 FPDs from the solid working casts (S group). The casts were digitized using a dental desktop scanner to establish virtual casts and design the FPDs using CAD. The definitive 3-unit monolithic zirconia FPDs were fabricated via a CAM milling process. The seated FPDs on the reference cast underwent digital evaluation for marginal and internal fit. The Mann-Whitney U test was applied for statistical comparison between the two groups (α = 0.05). Results: The RD group showed significantly higher discrepancies in fit for both premolars and molars compared to the S group (P < 0.05), particularly in terms of marginal and occlusal gaps. Color mapping also highlighted more significant deviations in the RD group, especially in the marginal and occlusal regions. Conclusion: The study found that the discrepancies in marginal and occlusal fits of 3-unit monolithic zirconia FPDs were primarily associated with those fabricated using the removable die system. This indicates the significant impact of the fabrication method on the accuracy of FPDs.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.91-98
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• 2011

Purpose: To assess the usefulness of implanted fiducial markers in the setup of hypofractionated radiotherapy for prostate cancer patients by comparing a fiducial marker matched setup with a pelvic bone match. Materials and Methods: Four prostate cancer patients treated with definitive hypofractionated radiotherapy between September 2009 and August 2010 were enrolled in this study. Three gold fiducial markers were implanted into the prostate and through the rectum under ultrasound guidance around a week before radiotherapy. Glycerin enemas were given prior to each radiotherapy planning CT and every radiotherapy session. Hypofractionated radiotherapy was planned for a total dose of 59.5 Gy in daily 3.5 Gy with using the Novalis system. Orthogonal kV X-rays were taken before radiotherapy. Treatment positions were adjusted according to the results from the fusion of the fiducial markers on digitally reconstructed radiographs of a radiotherapy plan with those on orthogonal kV X-rays. When the difference in the coordinates from the fiducial marker fusion was less than 1 mm, the patient position was approved for radiotherapy. A virtual bone matching was carried out at the fiducial marker matched position, and then a setup difference between the fiducial marker matching and bone matching was evaluated. Results: Three patients received a planned 17-fractionated radiotherapy and the rest underwent 16 fractionations. The setup error of the fiducial marker matching was $0.94{\pm}0.62$ mm (range, 0.09 to 3.01 mm; median, 0.81 mm), and the means of the lateral, craniocaudal, and anteroposterior errors were $0.39{\pm}0.34$ mm, $0.46{\pm}0.34$ mm, and $0.57{\pm}0.59$ mm, respectively. The setup error of the pelvic bony matching was $3.15{\pm}2.03$ mm (range, 0.25 to 8.23 mm; median, 2.95 mm), and the error of craniocaudal direction ($2.29{\pm}1.95$ mm) was significantly larger than those of anteroposterior ($1.73{\pm}1.31$ mm) and lateral directions ($0.45{\pm}0.37$ mm), respectively (p<0.05). Incidences of over 3 mm and 5 mm in setup difference among the fractionations were 1.5% and 0% in the fiducial marker matching, respectively, and 49.3% and 17.9% in the pelvic bone matching, respectively. Conclusion: The more precise setup of hypofractionated radiotherapy for prostate cancer patients is feasible with the implanted fiducial marker matching compared with the pelvic bony matching. Therefore, a less marginal expansion of planning target volume produces less radiation exposure to adjacent normal tissues, which could ultimately make hypofractionated radiotherapy safer.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.164-171
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• 1997

Heart transplantation is now accepted as a definitive therapeutic modality in patients with terminal hear failure. The first successful heart transplantation in humans was done in 1967 and the first case in Korea was performed in november, 1992. Since the first case in 1992, more than 50 cases have been performed in Korea. A total of 20 patients underwent orthotopic heart transplantation since November, 1992 in Asan Medicla Center. The purpose of this study is to evaluate the early results and the follow-up course of 20 cases of heart transplantation done in Asan Medical Center. The average age of 20 patients was 39.9$\pm$11.8 years old(20~58). The mean follow-up duration was 14.4$\pm$11.2 months(1~41). All patients are alive till now. The blood type was identical in 14 and compatible in 6 patients. ihe original heart disease was dilated cardiomyopathy in 16, valvular heart disease in 2, ischemic cardiomyopathy in 1, and giant cell myocarditis in 1 patient. HLA cross matching for recipient and donor was done in 18 cases and the results were negative for T-cell and B-cell in 16 patients, pos tive for warm B-cell in 2 patients. Among 6 loci of A, B, and DR, one locus was matched in 8 cases, 2 loci in 5 cases, and 3 loci matched in 1 case. The number of acute allograft rejection averaged 2.8$\pm$0.5 (0~6) per case and the number of acute allograft rejection requiring treatment averaged 1.0$\pm$0.9 (1~3) per case. The time interval from operation to the first acute rejection requiring treatment was 35.5$\pm$20.4 days (5~60). Acute humoral rejection was suspected strongly in 1 case and was successfully treated. The left ventricular ejection fraction measured by echocardiography and/or MUGA scan was dramatically increased from 17.5$\pm$6.8 (9~32)% to 58.9$\pm$2.0 (55~62)% after heart transplantation. Temporary pacing was needed in 5 patients over 24 hours but normal sinus rhythm appeared within 7 days in all cases. One patient has been taken permanent pacemaker implantation due to complete AV block appearing 140 days after heart transplantaion. One patient had cyclosporine-associated n urotoxicity during the immediate postoperative period and was recovered after 27 hours. The heart transplantation of Asan Medical Center is on a developing stage but the early result is comparable to that of well established centers in other countries, even though the long-term follow-up result must be reevaluated. We can conclude that the heart transplantion is a promising therapeutic option in patients with terminal heart failure.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.2
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• pp.129-146
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• 2008

The aim of this study was to compare and analyze wear resistance of acrylic resin tooth in denture opposing to different types of restoration materials. Also, it aimed to compare and analyze the hardness of three various types of resin artificial teeth when using five different types of denture detergents. In this study three types of artificial teeth were used. As ordinary acrylic resin tooth $Trubyte^{(R)}Biotone^{(R)}$ (Dentsply, U.S.A.) was used, and as high hardness resin tooth Endura $Posterio^{(R)}$ (Shofu, Japan) and Physio $Duracross^{(R)}$ (Nissin, Japan) were used. To compare wear resistance, gold alloy, dental porcelain, and composite resin were used as opposing restorations. In addition, with three types of resin tooth stated above, five types of denture detergents, which are $Yuhanrox^{(R)}$ (Yuhanclorox, Korea), $Polident^{(R)}$ (Yuhan Co., Korea), $Cidex^{(R)}OPA$ (Johnson & Johnson Medical Co., Korea), $Hexamedin^{(R)}$ (Bukwang Pharm Co., Korea) and Daihan sterile $water^{(R)}$ (Daihan Pharm Co., Korea) were used to compare and analyze the effects denture detergents have on the surface hardness. The results of this study were as follow : 1. When composite resin and dental porcelain were used as the opposing restorations, $Trubyte^{(R)}$ $Biotone^{(R)}$, Endura $Posterio^{(R)}$, Physio $Duracross^{(R)}$ in ascending order showed decrease of cusp height with significant difference (p<0.05). 2. When gold alloy was used as opposing restoration, there was decrease in the cusp height in order of $Trubyte^{(R)}Biotone^{(R)}$, Endura $Posterio^{(R)}$, Physio $Duracross^{(R)}$ and $Trubyte^{(R)}$ $Biotone^{(R)}$ especially showed significant decrease in high cusp height as compared to two other types of artificial tooth (p<0.05). 3. When composite resin, gold alloy and dental porcelain were used as opposing restorations, $Trubyte^{(R)}$ $Biotone^{(R)}$, Endura $Posterio^{(R)}$, Physio $Duracross^{(R)}$ in order decreased greatly in weight and these three materials showed significant difference (p<0.05). 4. Comparing the experiment values, decrease in strength had significant difference in all resin artificial teeth before and after the denture detergents were used (p<0.05). 5. When resin artificial teeth were subsided in $Yuhanrox^{(R)}$, $Cidex^{(R)}OPA$, and $Hexamedin^{(R)}$, $Trubyte^{(R)}$ $Biotone^{(R)}$, Endura $Posterio^{(R)}$, Physio $Duracross^{(R)}$ in order showed decrease in hardness, and $Trubyte^{(R)}$ $Biotone^{(R)}$ especially showed significant high decrease hardness as to other two types of artificial teeth (p<0.05). Therefore, Physio $Duracross^{(R)}$ seems to have superior wear resistance, and together with Endura $Posterio^{(R)}$, it presents excellent hardness as compared to $Trubyte^{(R)}$ $Biotone^{(R)}$. However, since this study is fragmentary, it should be given careful consideration and more study need to be done before making a definitive conclusion.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.139-146
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• 2002

Purpose : This study evaluated the treatment outcomes, patterns of failure, and treatment related complications of primary lymphoma patients who received definitive radiation therapy. Materials and Methods : A retrospective analysis was undertaken for 31 patients with primary orbital lymphoma at the Asan Medical Center between February 1991 and April 2001. There were 18 males and 13 females with ages ranging from 3 to 73 years (median, 44 years). The involved sites were 9 conjunctivae, 12 eyelids and 10 other orbits. The histological types were 28 MALT lymphomas (low-grade B-cell lymphoma of mucosa-associated lymphoid tissue type), 1 diffuse large B-cell lymphoma, 1 anaplastic large cell lymphoma and 1 lymphoblastic lymphoma. The Ann Arbor stages were all IE $(100\%)$. Ann Arbor stage III or IV patients were excluded from this study, Bilateral orbital involvement occurred in 6 cases. Radiation therapy was given with one anterior port of high energy electrons $(6\~16\;MeV)$ for the lesions located at the anterior structures like the conjunctivae or eyelids. Lesions with a posterior extension or other orbital lesions were treated with 4 or 6 MeV photons with appropriately arranged portals. In particular, lens blocks composed of lead alloy were used in conjunctival or eyelid lesions. Twelve patients received chemotherapy. The median follow-up period was 53 months. Results : The 5-year overall, cause-specific, and disease-free survival was $91\%,\;96\%,\;and\;80\%$, respectively. The complete response rate 6 months after radiation therapy was $100\%$. Local recurrences were observed in 2 patients at 16 and 18 months after completion of radiation treatment. They were salvaged with additional radiation therapy. Two patients developed distant metastases. A MALT lymphoma patient with a lung relapse was successfully salvaged with radiotherapy, but the other lymphoblastic lymphoma patient with bone marrow relapse expired. There were no severe complications but 5 patients developed radiation-induced cataracts and 2 patients developed dry eye. Conclusion : Most primary orbital lymphomas consisted of MALT lymphomas. Radiation therapy was a successful treatment modality for orbital lymphoma without any severe complications. In cases of local relapses, radiation therapy is also a very successful salvage treatment modality.

• Korean Security Journal
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• no.1
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• pp.371-408
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• 1997

This article is the reserch on actual condition of crime of arson which occurs in Korea and its countermeasures. The the presented problem in this article are that (1) we have generally very low rate concern about the crime of arson contrary to realistic problems of rapid increase of crime of arson (2) as such criminal motives became so diverse as to the economic or criminal purpose unlike characteristic and mental deficiency of old days, and to countermeasure these problems effectively it presentation the necessity of systemantic research. Based on analysis of reality of arson, the tendency of this arson in Korea in the ratio of increase is said to be higher than those in violence crime or general fire rate. and further its rate is far more greater than those of the U.S.A. and Japan. Arson is considered to be a method of using fire as crime and in case of presently residence to be the abject, it is a public offense crime which aqccompany fatality in human life. This is the well It now fact to all of us. And further in order to presentation to the crime of arson, strictness of criminal law (criminal law No, 164 and 169, and fire protection law No. 110 and 111) and classification of arsonist as felony are institutionary reinforced to punish with certainty of possibility, Therefore, as tendency of arson has been increased compared to other nations, it is necessary to supplement strategical policy to bring out overall concerns of the seriousness of risk and damage of arson, which have been resulted from the lack of understanding. In characteristics analysis of crime of arson, (1) It is now reveald that, in the past such crime rate appeared far more within the boundary of town or city areas in the past, presently increased rate of arsons in rural areas are far more than in the town or small city areas, thereby showing characteristics of crime of arson extending nation wide. (2) general timetable of arson shows that night more than day time rate, and reveald that is trait behavior in secrecy.(3) arsonists are usually arrested at site or by victim or report of third person(82,9%).Investigation activities or self surrenders rate only 11.2%. The time span of arrest is normally the same day of arson and at times it takes more than one year to arrest. This reveals its necessity to prepare for long period of time for arrest, (4) age rate of arson is in their thirties mostly as compared to homicide, robbery and adultery, and considerable numbers of arsons are in old age of over fifties. It reveals age rate is increased (5) Over half of the arsonists are below the junior high school (6) the rate of convicts by thier records is based on first offenders primarily and secondly more than 4 time convicts. This apparently shows necessity of effective correctional education policy for their social assimilation together with re-investigation of human education at the primary and secondary education system in thier life. The examples of motivation for arosnits, such as personal animosity, fury, monetary swindle, luscious purpose and other aims of destroying of proof, and other social resistance, violence including ways of threatening, beside the motives of individual defects, are diverse and arsonic suicide and specifically suicidal accompany together keenly manifested. When we take this fact with the criminal theory, it really reveals arsons of crime are increasing and its casualities are serious and a point as a way of suicide is the anomie theory of Durkheim and comensurate with the theory of that of Merton, Specifically in the arson of industrial complex, it is revealed that one with revolutionary motive or revolting motive would do the arsonic act. For the policy of prevention of arsons, professional research work in organizational cooperation for preventive activities is conducted in municipal or city wise functions in the name of Parson Taskforces and beside a variety of research institutes in federal government have been operating effectively to countermeasure in many fields of research. Franch and Sweden beside the U.S. set up a overall operation of fire prevention research funtions and have obtained very successful result. Japan also put their research likewise for countermeasure. In this research as a way of preventive fire policy, first, it is necessary to accomodate the legal preventitive activities for fire prevention in judicial side and as an administrative side, (1) precise statistic management of crime of arson (2) establishment of professional research functions or a corporate (3) improvement of system for cooperative structural team for investigation of fires and menpower organization of professional members. Secondly, social mentality in individual prospect, recognition of fires by arson and youth education of such effect, educational program for development and practical promotion. Thirdly, in view of environmental side, the ways of actual performance by programming with the establishment of cooperative advancement in local social function elements with administrative office, habitants, school facilities and newspapers measures (2) establishment of personal protection where weak menpowers are displayed in special fire prevention measures. These measures are presented for prevention of crime of arson. The control of crime and prevention shall be prepared as a means of self defence by the principle of self responsibility Specifically arsonists usually aims at the comparatively weak control of fire prevention is prevalent and it is therefore necessary to prepare individual facilities with their spontaneous management of fire prevention instead of public municipal funtures of local geverment. As Clifford L. Karchmer asserted instead of concerns about who would commit arson, what portion of area would be the target of the arson. It is effective to minister spontaveously the fire prevention measure in his facility with the consideration of characteristics of arson. On the other hand, it is necessary for the concerned personnel of local goverment and groups to distribute to the local society in timely manner for new information about the fire prevention, thus contribute to effective result of fire prevention result. In consideration of these factors, it is inevitable to never let coincide with the phemonemon of arsons in similar or mimic features as recognized that these could prevail just an epedemic as a strong imitational attitude. In processing of policy to encounter these problems, it is necessary to place priority of city policy to enhancement of overall concerns toward the definitive essense of crime of arson.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.1 no.1
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• pp.53-68
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• 1981

Most clays under sustained load exhibit time-dependent deformation because of creep movement of soil particles and many investigators have attempted to relate their findings to the creep behavior of natural ground and to the long-term stability of slopes. Since the creep behavior of clays may assume a variety of forms depending on such factors as soil plasticity, activity and water content, it is difficult and complicated to analyse the creep behavior of clays. Rheological models composed of linear springs in combination with linear or nonlinear dashpots and sliders, are generally used for the mathematical description of the time-dependent behavior of soils. Most rheological models, however, have been proposed to simulate the behavior of secondary compression for saturated clays and few definitive data exist that can evaluate the behavior of non-saturated clays under the action of sustained stress. The clays change gradually from a solid state through plastic state to a liquid state with increasing water content, therefore, the rheological models also change. On the other hand, creep is time-dependent, and also the effect of thixotropy is time-function. Consequently, there may be certain correlations between creep behavior and the effects of thixotropy in compacted clays. In addition, the states of clay depend on water content and hence the height of the specimen under drained conditions. Futhermore, based on present and past studies, because immediate elastic deformation occurs instantly after the pressure increment without time-delayed behavior, the factor representing immediate elastic deformations in the rheological model is necessary. The investigation described in this paper, based on rheological model, is designed to identify the immediate elastic deformations and the effects of thixotropy and height of clay specimens with varing water content and stress level on creep deformations. For these purposes, the uniaxial drain-type creep tests were performed. Test results and data for three compacted clays have shown that a linear top spring is needed to account for immediate elastic deformations in the rheological model, and at lower water content below the visco-plastic limit, the effects of thixotropy and height of clay specimens can be represented by the proposed rheological model not considering the effects. Therefore, the rheological model does not necessitate the other factors representing these effects. On the other hand, at water content higher than the visco-plastic limit, although the state behavior of clays is visco-plastic or viscous flow at the beginning of the test, the state behavior, in the case of the lower height sample, does not represent the same behavior during the process of the test, because of rapid drainage. In these cases, the rheological model does not coincide with the model in the case of the higher specimens.