• The Journal of Korean Academy of Prosthodontics
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• v.38 no.3
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• pp.360-365
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• 2000

The completely edentulous patient has few treatment options in conventional dentistry. When implants are considered, treatment plans range from a 2-implant overdenture to a completely implant-supported prosthesis. Fixed prosthesis is often the preferred selection of the edentulous patient. fixed full-arch cert amo-metal restorations can be a predictable implant treatment modality for the edentulous patient. Implant-supported fixed prosthesis has several advantages: predictability, fixedness, retrievability, improved function, lower maintenance of prosthesis, long-term published success. Edentulous patients with a severely resorbed mandible often experience problems with their dentures. Treatment concepts involving two to four implants for the support of an overdenture have been proposed. There seems to be no need to insert more than two endosteal implants to support an overdenture, however, long-term prospective studies are needed to support this notion. Using short endosseous implants and an overdenture in the extremely resorbed mandible is a justified treatment option because of the relative simplicity and low morbidity of this treatment strategy. Implant-supported overdenture has several advantages: Cost, retrievability, hygiene access, profile and contour control, increased retention and stability, implant installed in a predicted region(ant. mandible).

• Journal of Welding and Joining
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• v.34 no.1
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• pp.68-74
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• 2016

Adoption of narrow gap welding shall be increased for the butt joint of thick plate, because the deformation and welding cost is reduced by decrease of cross-sectional area. However, sometimes narrow gap causes defects such as lack of fusion since it has small groove angle and narrow groove width. Therefore, GMAW, GTAW and SAW process shall be adopted to narrow gap welding with small bead hight and low deposition rate. In this study, Super-TIG welding using C-type strip was applied to semi-narrow gap butt joint in order to increase the welding productivity. High deposition rate 10kg/hr was obtained by high current 600A without undercut, humping bead and other welding defects. Measuring the mean and standard deviation of the melting depth to evaluate the developed processes, the fusion line type was determined by measuring the difference between maximum and minium melting depth. Furthermore, a model on arch fusion line and linear fusion line was suggested in order to prevent LF on groove wall in narrow gap butt welding.

• The Journal of the Korean bone and joint tumor society
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• v.5 no.1
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• pp.76-81
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• 1999

Aneurysmal bone cysts are uncommon bony lesions of the spine. Approximately 3-20% of the aneurysmal bone cysts occur in the spine, predominantly in the lumbar region, but they may occur at the any level of the spine. These lesions commonly arise from the neural arch and occasionally invade the pedicle and the vertebral body. The clinical diagnosis of a spinal lesion can be very difficult in the early stages of the disease because specific symptoms and signs are usually absent or only amount to back pain. However, depending on the level of involvement and the extent of neurological compression, a wide variety of neurological symptoms and signs may appear, ranging from mild radicular symptoms to complete paraplegia or tetraplegia. Available treatment options include complete excision or curettage of the lesion with bone graft, but where excision cannot be achieved, low dose radiation or arterial embolization may be used. We report a case of aneurysmal bone cyst in the pedicle of the T10 spine with nonstructural scoliosis of $40^{\circ}$ Cobb's angle which was treated successfully with only curettage of the lesion.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.258-264
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• 1985

The experience with operative treatment for total correction of Fallot at the department of Thoracic and Cardiovascular Surgery, Keimyung University Dong San Medical Center from July 1980 to July 1984 was reviewed. There were 37 males and 12 females and their ages ranged from 3 years to 30 years, with the average age of 12.2 years. Sixty nine point four percent of patients were younger than 15 years of age. The most frequent type of right ventricular outflow stenosis was the combined type [pulmonary valvular and infundibular stenosis] containing 41 patients [83.7%] and there were 9 deaths in this group. The major associated lesions included Patent foramen ovale in 20 patients [40.8%], Atrial septal defect in 7 patients [14.3%], Left superior vena cava in 4 patients [8.2%], Right sided aortic arch in 2 patients [4.1%] and Patent ductus arteriosus in 11 patient [2.0%]. The pulmonary valvotomy was performed in 41 patients and patch graft reconstruction of the right ventricular outflow tract was performed in 23 patients. In 11 patients the monocusp patches were used. Thirty-five patients [71.4%] had the right bundle branch block postoperatively. There were 11 postoperative deaths with hospital mortality rate of 22.4% and the leading causes of death were low output syndrome, bleeding, and cerebral embolism.

• Journal of Chest Surgery
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• v.23 no.2
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• pp.253-259
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• 1990

Between January, 1970 and August, 1989, a total of 81 patients whose age were more than 20 years of life, received total correction for tetralogy of Fallot. This report analyzed 70 patients among them and excluded the remaining 11 patients whose clinical data could not be found. Their mean age was 25.750.39 years[range 20 \ulcorner50]. The clinical manifestations were cyanosis and clubbing [64 pts], frequent URI[40 pts], anoxic spell [19 pts], infective endo-carditis[4 pts], brain abscess[3 pts], pulmonary tuberculosis[3 pts] and CHF, chest tightness, nephrotic syndrome, left hemiplegia, and tamponade. The types of right ventricular outflow tract obstruction were combined[46 pts], pure infundibular [21 pts] and pure valvular[3 pts]. Associated cardiovascular anomalies were PFO [27 pts], ASDi8 pts], LSVC[8 pts], aortic regurgitation [5 pts], right aortic arch, coronary artery anomalies, PDA and dextrocardia. Hospital mortality was 5.7%. The causes of death ware low cardiac output [2 pts], aggravation of CRF[1 pts] and brain damage[1 pts]. There was one late death because of residual intracardiac shunt and congestive heart failure. During the follow-up period, 16 patients were lost and the remaining 49 patients were asymptomatic and leading normal lives. Residual intracardiac shunt was detected in 5 patients with radionuclide single pass study but all of them had Qp / Qs ratio less than 1.5.

• Journal of Chest Surgery
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• v.24 no.2
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• pp.153-160
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• 1991

Tetralogy of Fallot was repaired by a transatrial-transpulmonary approach in 91 of 250 patients treated surgically [including redo operations] between April 1986 and December 1989. Their age ranged from 6 months to 14 years [mean 39.7 months]. Associated cardiovascular anomalies were right aortic arch [n=22], ASD [n=12], PDA [n=5], persistent left SVC [n=5], and others [n=6]. PA index was measured pre-operatively since 1987 to estimate pulmonary artery size and safe total correction[mean 289$\pm$110mm2/BSA]. Eight patients received previous shunt take down procedure concomitantly. Pulmonary arteriotomy was extended through small pulmonary annulus to a minimal distance upon the right ventricular infundibulum and transannular patch was applied in 38 patients [41.3%], in 31 of them monocuspid patch was utilized. pRV/LV was measured at operation room in 77 patients [mean 0.58$\pm$0.36]. Operative mortality was 6.6% [6/91]. The causes of death were low cardiac output [n=5], arrhythmia[n=1] and respiratory failure [n=1]. At follow-up between 12 months and 57 months [mean 30.8 months] most patients were in New York Heart Association class I without cardiac medication. There was no late death, but reoperations were required in 3 patients to relieve residual right ventricular outflow obstruction. Thus successful repair of tetralogy of Fallot can be accomplished in most patients including infants by transatrial-transpulmonary approach and the better result can be anticipated with respect to postoperative right ventricular function and arrhythmia than the conventional transventricular approach.

• The korean journal of orthodontics
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• v.17 no.1
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• pp.33-45
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• 1987

This study was designed to examine relations between posture and size of the tongue and dentoalveolar pattern. The sample was consisted of three groups, the 34 subjects of Normal occlusion, the 31 subjects of Bimaxillary protrusion and the 31 subjects of Class III malocclusion. On the cephalograms, lengths, heights and areas of the tongue and intermaxillary space and on the study model, arch length, intercanine width, intermolar width and palatal height were measured. These data from measuring cephalograms and models were statistically analyzed. The results of the study were as follows; 1. Length of the tongue was the greatest in Bimaxillary protrusion and in order of Normal occlusion and Class III malocclusion. 2. Posture of the tongue was the lowest in Class III malocclusion and in order of Bimaxillary protrusion and Normal occlusion. 3. There were a tendency to be larger area of tongue and intermaxillary space in Class III malocclusion compared to Normal occlusion and Bimaxillary protrusion. 4. Size of the tongue and intermaxillary space showed low correlations with the dentoalveolar pattern.

• The korean journal of orthodontics
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• v.16 no.2
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• pp.43-51
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• 1986

The highly accurate laser holographic interferemotry method was used to determine in what way low-magnitude forces during maxillary expansion are transmitted to the entire maxillary complex and its surrounding structures. The experiments were carried out on a dryed human skull which had a perfectly preserved, normally aligned maxillary dental arch and intact alveolar process. The skull was fixed within a constructed metal frame which ensured maximal stability of the object. The optical equipment and the object were mounted on antivibration table. Interferograms were taken on the lateral and frontal sides of the maxillary complex, using the 10mW He-Ne laser and the double-exposure method. Analysis of the fringe pattern on the recorded object surface was performed by graphically determining the deformation curves related to the bony surface in selected horizontal and vertical planes. On the basis of this study, the following conclusions can be drawn: 1. The density of the interference fringes was gradually increased with the degree of expansion force. 2. Mechanical reactions on the maxillary complex, circummaxillary sutures, and surrounding bones were clearly visible, even with the lowest loading degree. 3. The amount of bone displacement was greater in application of the force after $90^{\circ}$ turn than in initial application of the same force. 4. The direction of interference fringes on the bony surface was similar at all loading degrees.

• Imaging Science in Dentistry
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• v.38 no.2
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• pp.103-107
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• 2008

Purpose: The purpose of this study was to evaluate the relationship between the position of mesiodens and its complications. Materials and Methods: The subjects for this study consisted of 172 patients with mesiodens. Panoramic radiographs and cross-sectional tomography were taken of all of the subjects. Their clinical records and radiographs were analyzed in order to study the direction and vertical and sagittal position of mesiodens, as well as complications caused by mesiodens. Results: The number of mesiodens was one in 112 cases (65.1%) and two in 60 cases (34.9%). Complications were found in 121 mesiodentes (52.2%), with being median diastema the most frequent. The incidence of complications was high in erupted mesiodens (75.0%), in horizontal mesiodens (89.8%) and in mesiodens located within the arch (75.7%), but was low in mesiodens impacted above apex (29.8%), in normal position (34.4%) and in palatally positioned mesiodens (46.5%). Conclusion: It was suggested that the frequency of complications was different according to the vertical position, the direction of the crown and the sagittal position.

• Tunnel and Underground Space
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• v.25 no.3
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• pp.244-254
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• 2015

The tunnel is excavated through the alluvial layer composed of sand and gravel with groundwater deposited on rock. A portion of upper part of the tunnel is located in the alluvial layer and there are several buildings just above the curved section of the tunnel. It is necessary to prevent from sand-flowing into the tunnel due to low strength of the alluvial, high groundwater level and shallow depth of the tunnel from the ground surface. For this, the alluvial around the tunnel is pre-reinforced by umbrella arch method with multi-stage grouting through large diameter steel pipes or jet grouting before excavating the tunnel. The effect of the pre-reinforcement of the tunnel and the safety of the buildings are monitored by measurement of ground deformation occurred during tunnelling.