• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.150-160
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• 2005

Background: For normalization of displaced anatomical structure by large cyst, two-step procedure (decompression and enucleation afterward) has been recommended. However, the histological transformation after cystotomy for decompression was shown frequently in secondary enucleation. Therefore, analyses about effects and histological changes after decompression have been necessary. Methods: 48 cases diagnosed as large odontogenic cyst in the jaw and treated by decompression and secondary enucleation were retrospectively analyzed in clinical, rediographical, and histological aspects. Results: In dentigerous cyst, decompression was much useful. Impacted permanent teeth were erupted and reduction rate was higher than that of odontogenic keratocyst (OKC) and apical periodontal cyst. In OKC, among the 29 cases, 11 cases showed no-keratosis, proliferation and rete-ridge elongation after decompression. 4 cases showed no-keratosis, only. 7 cases showed orthokeratosis and rete-ridge elongation and 6 cases showed reteridge elongation, only. 1 case had no change. And the recurrence rate for OKCs was 10.3%. For all odontogenic cysts in this study, dysplasia was not found in cystic lining after decompression. Conclusions: This study implied that decompression for large odontogenic cyst was useful treatment modality because it was conservative treatment and recurrence rate was low although long treatment period was required.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.27-37
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• 1993

The purpose of this study was to determine the fluroide release levels of new fluoride-containing liner/base cements and the fluoride uptake by dentin surfaces. Ten specimens of each brand (Fuji ionomer Type III, Fuji Lining LC, Timeline, Vitrebond and XR ionomer) were made, polymerized and placed in fluoride-free distilled water at $37^{\circ}C$, 100% relative humidity for 24 hours. The extracting solution of specimen was exchanged and fluoride release was measured daily for the 30 days. For fluoride uptake study, twenty-five extracted human lower molars were sectioned longitudinally in the mesiodistal direction with a diamond disc. Five teeth were filled with each material and then stored at $37^{\circ}C$, 100% humidity for 4 weeks. Fluoride uptake by dentin from the test materials was evaluated using electron probe micro X-ray analyzer. The following results were obtained : 1. The amounts of fluoride release showed no significant difference between Fuji ionomer Type III and Fuji Lining LC, but showed significant difference between other groups. XR ionomer released significantly greater fluoride than any other group(P<.001). 2. All the materials have a burst effect which more fluoride released in then first 3 day and showed significant decrease over the test period (P<0.001). 3. XR ionomer group showed fluoride penetration to approximately $50{\mu}m$ deep in dentin. But other material groups showed very little fluoride uptake by dentin.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.16.1-16.11
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• 2022

Background: Antimony is used in catalysts, pesticides, brake systems, pharmaceuticals, and synthetic fire retardants in the plastic, paint, and rubber industries. Accumulation of trivalent antimony compounds in the body can cause cardiotoxic effects and increase the risk of electrocardiogram (ECG) abnormalities and sudden death. Antimony exposure can result in action potential prolongation, causing a cardiac repolarization delay, which appears as QTc prolongation and T-wave abnormalities on the ECG. There are no studies on antimony-associated cardiac toxicity in Korea. Case presentation: Accordingly, the present study reports cases of ECG abnormalities in workers handling antimony trisulfide at a company located in the Gyeongsangbuk-do region. Nineteen workers employed at an automobile brake lining manufacturer were exposed to antimony trisulfide dust through thermoforming, grinding, and drilling processes. In 2020, the workers were reported to work 12-hour shifts, 5 days a week. The time-weighted average (TWA) of antimony trisulfide exposure measured in workers was 0.0028 mg/m³. Two workers were excluded from the analysis due to pre-existing medical conditions (cardiovascular disease). Of the remaining 17 workers, ECG abnormalities were found in 41% (seven out of 17: four with QTc prolongation and T-wave abnormalities; two with only T-wave abnormalities; and one with only QTc prolongation). Conclusions: This case report outlines the first few cases in Korea in which potential cardiac toxicity caused by occupational exposure to antimony was identified. However, data regarding cardiac toxicity caused by antimony exposure are still lacking in Korea; thus, additional studies are needed to identify causal relationships.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.259-267
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• 2008

This in vitro study aimed to investigate the influence of flowable composite lining with different thicknesses on the marginal quality. One hundred twenty cavities, each preparated with proximal boxtype( 3mm of bucco-lingual width, 2mm of mesio-distal depth and gingival margin of 1mm supra-CEJ) were randomly dived into four groups. group I : Tetric ceram filling alone(control group) group II: 0.5mm thickness Tetric flow + Tetric ceram filling group III: 1.5mm thickness Tetric flow + Tetric ceram filling group IV: 2.5mm thickness Tetric flow + Tetric ceram filling The followings are the results: 1. Group II showed significantly less microleakage compared to group I(control group)(p<0.05). 2. There was no statistically significant difference between group III, IV and group I(p>0.05). 3. Group II showed significantly less microleakage compared to group III, IV(p<0.05). 4. There was microleakage more or less in all group. It was concluded that 0.5mm flowable composite lining improved cavity adaptation and marginal sealing.

• The Journal of the Korean dental association
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• v.21 no.12 s.175
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• pp.991-995
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• 1983

A radicular cyst is a slowly-growing epithelial sac lining a pathologic cavity in the bone at the apex of a tooth. Large radicular cyst revealed by radiographic examination almost always appear to involved several teeth. The author observed a 31 year old woman with a labial swelling and palatal mucosal expansion of the maxillary anterior region. Radiographic examination indicated that the lesion extended from the left maxillary lateral incisor to the right lateral incisor. Cyst consisted of tan to gray yellow slightly firm to partly hard plaque like tissue measuring 3.4 x 2.2 x 0.3㎝. The author has treated the cyst by means of enucleation with apicoecomies of the involved teeth except the right central incisor. Recovery proceed satisfactorily and there were no clinical or radiologic signs of recurrence 8 months later.

• Proceedings of the Korean Geotechical Society Conference
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• 1990.10a
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• pp.35-50
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• 1990

This paper describes the importance of incorporating the titre-dependent deformation behaviour in the design and construction of tunnels in swelling rocks. Two tunnel projects, in which authors got involved in Canada, are chosen to demonstrate the importance. In diversion tunnels for Oldman River Dan Projects time-dependent deformation characteristics of the mudrocks obtained from teat tunnel program were neglected in the design and construction of the tunnels and several sectional of concrete lining in tunnels were cracked extensively. In SABNGS No.3 Projects an extensive experimental program was carried out to study time-dependent deformation behaviour of highly swelling Queenston shale, with the air of establishing the constitutional relationship for the rock-structure time interaction analysis.

• Geomechanics and Engineering
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• v.15 no.3
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• pp.911-917
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• 2018

This paper concerns a numerical investigation on the effect of construction sequence on three-arch (3-Arch) tunnel behavior. A three-arch tunnel section adopted in a railway tunnel construction site was considered in this study. A calibrated 3D finite element model was used to conduct a parametric study on a variety of construction scenarios. The results of analyses were examined in terms of tunnel and ground surface settlements, shotcrete lining stresses, loads and stresses developed in center column in relation to the tunnel construction sequence. In particular, the effect of the side tunnel construction sequence on the structural performance of the center structure was fully examined. The results indicated that the load, thus stress, in the center structure can be smaller when excavating two side tunnels from opposite direction than excavating in the same direction. Also revealed was that no face lagging distance between the two side tunnels impose less ground load to the center structure. Fundamental governing mechanism of three-arch tunnel behavior is also discussed based on the results.

• Journal of the Korean Home Economics Association
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• v.37 no.12 s.142
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• pp.141-151
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• 1999

This study was carried out to examine the effects of textile materials for thermal insulation value using a thermal manikin. Cotton, polyester, wool, silk and rayon were selected as outer wears like blouses, skirts, slacks, and one-pieces. Acetate was chosen as a lining. Brief and long sleeve upper underwear(cotton) were chosen as the inner wears. The results were as follows; There were no significant differences among the materials in skirts and blouse-skirt suits by the thermal manikin. However blouses, slacks, one-pieces and blouse-slacks suits were showed the effects of materials. Blouse-slacks suits was showed the highest thermal insulation value and one-piece had the lowest thermal insulation value.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.2
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• pp.178-181
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• 2008

Much has been written about the possibility that the lining of a dentigerous cyst might undergo neoplastic transformation to an ameloblastoma which is defined as mural ameloblastoma. Mural ameloblastomas are estimated to constitute 5% of all ameloblastomas. 85% of the mural ameloblastomas were associated with dentigerous cyst, all of which were observed before the age of 30. The frequency of recurrence after simple enucleation of the cyst containing this lesion is considerably lower than that for ameloblastomas in general that are treated in a similar manner. Therefore, further and more extensive surgery is not required for mural ameloblastoma. We diagnosed a cystic appearance of a 17 year-old female as dentigerous cyst and undergone marsupialization. For 2 years of period, no significant change was observed and therefore enucleation was undergone and diagnosed as ameloblastoma. We report this case with a review of related literatures.

• Clinics in Shoulder and Elbow
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• v.18 no.2
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• pp.102-104
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• 2015

In this report, a case of a 70-year-old man with a large ganglion cyst formed after anterior transposition of the left ulnar nerve is presented. Three months after the index surgery, the patient presented with a painless superficial ovoid, soft mass measuring $5{\times}4{\times}2cm$ in size located at the posteromedial aspect of the left elbow, the previously operated site. Magnetic resonance imaging showed a well demarcated cystic mass with a stalk connecting to the elbow joint. Excisional biopsy was performed and pathologic findings showed that the cystic wall had no definite lining cells with myxoid degeneration compatible with findings of ganglion cyst.