• 대한치과기공학회지
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• 제42권2호
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• pp.81-89
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• 2020

Purpose: This in vitro study was conducted to evaluate the marginal and internal fit of three-unit Co-Cr frameworks fabricated by computer-aided metal milling and direct metal laser sintering(DMLS) systems in comparison to conventional casting method. Methods: Three-unit Co-Cr frameworks were fabricated by conventional wax up with casting(CWC), computer-aided metal milling(MM) and direct metal laser sintering(DMLS)(n=10 each). The marginal and internal fit of specimens were examined using a light-body silicone impression material. The thickness of light-body silicone was measured at eight reference points each, divided in the mesio distal and bucco lingual directions. All measurements were conducted by a stereomicroscope. Digital photos were taken at 150× magnification and then analyzed using a measurement software. The Kruskal-Wallis test and Bonferroni correction were used for analyzing the results. Results: The mean(SD) is ㎛ for fabrication methods, the mean marginal fit were recorded respectively, DMLS 39(27), followed by CWC 63(38), MM 220(128). and the mean internal fit CWC 95(47), DMLS 116(49), MM 210(152). In addition, the largest gap was found in the occlusal surface area among the internal measurement areas of all groups. Conclusion: As a result, the direct metal laser sintering method showed better marginal and internal fit than the metal milling method. The marginal and internal fit were statistically different according to the three fabrication methods(p<0.001). Except the MM group, the marginal fit of the CWC and DMLS groups was below the clinical standard of 120 ㎛. Based on the results of this study, it can be applied to clinical use in the future.

• The Journal of Advanced Prosthodontics
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• 제9권4호
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• pp.265-270
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• 2017

PURPOSE. This study is to evaluate the internal fit of the crown manufactured by CAD/CAM milling method and 3D printing method. MATERIALS AND METHODS. The master model was fabricated with stainless steel by using CNC machine and the work model was created from the vinyl-polysiloxane impression. After scanning the working model, the design software is used to design the crown. The saved STL file is used on the CAD/CAM milling method and two types of 3D printing method to produce 10 interim crowns per group. Internal discrepancy measurement uses the silicon replica method and the measured data are analyzed with One-way ANOVA to verify the statistic significance. RESULTS. The discrepancy means (standard deviation) of the 3 groups are $171.6\;(97.4){\mu}m$ for the crown manufactured by the milling system and 149.1 (65.9) and $91.1\;(36.4){\mu}m$, respectively, for the crowns manufactured with the two types of 3D printing system. There was a statistically significant difference and the 3D printing system group showed more outstanding value than the milling system group. CONCLUSION. The marginal and internal fit of the interim restoration has more outstanding 3D printing method than the CAD/CAM milling method. Therefore, the 3D printing method is considered as applicable for not only the interim restoration production, but also in the dental prosthesis production with a higher level of completion.

• The Journal of Advanced Prosthodontics
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• 제10권5호
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• pp.367-373
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• 2018

PURPOSE. To evaluate the fit of a crown produced based on a 3D printed model and to investigate its clinical applicability. MATERIALS AND METHODS. A master die was fabricated with epoxy. Stone dies were fabricated from conventional impressions (Conventional stone die group: CS, n=10). Digital virtual dies were fabricated by making digital impressions (Digital Virtual die group: VD, n=10). 3D data obtained from the digital impression was used to fabricate 3D printed models (DLP die group: DD, n=10, PolyJet die group: PD, n=10). A total of 40 crowns were fabricated with a milling machine, based on CS, VD, DD and PD. The inner surface of all crowns was superimposed with the master die files by the "Best-fit alignment" method using the analysis software. One-way and 2-way ANOVA were performed to identify significant differences among the groups and areas and their interactive effects (${\alpha}=.05$). Tukey's HSD was used for post-hoc analysis. RESULTS. One-way ANOVA results revealed a significantly higher RMS value in the 3D printed models (DD and PD) than in the CS and DV. The RMS values of PD were the largest among the four groups. Statistically significant differences among groups (P<.001) and between areas (P<.001) were further revealed by 2-way ANOVA. CONCLUSION. Although the fit of crowns fabricated based on the 3D printed models (DD and PD) was inferior to that of crowns prepared with CS and DV, the values of all four groups were within the clinically acceptable range (<$120{\mu}m$).

• Clinical and Experimental Pediatrics
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• 제49권7호
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• pp.796-799
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• 2006

편측성 다낭성 신 이형성증과 폐의 선천성 낭성 선종양 기형은 각각 독립된 질환으로 배아 시기에 발생 과정의 문제로 생긴다고 알려져 있다. 폐의 선천성 낭성 선종양 기형에서 폐 외의 기형으로 신장 기형이 동반될 수 있으나 생존 가능성이 적어 사산아로 출생되는 경우가 많다. 저자들은 위장관염으로 입원한 21개월 남아에서 우연히 편측성 다낭성 신 이형성증을 발견했고, 이 과정에서 폐의 선천성 낭성 선종양 기형도 발견하였기에 보고하는 바이다.

• 한국조경학회지
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• 제44권5호
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• pp.38-46
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• 2016

본 연구의 목적은 실내조경공간에서의 수경시설의 도입이 이용자의 심리 및 생리에 미치는 효과를 정량적으로 분석하는 것이었다. 실험을 위해 실내에 식물로 구성된 조경공간과 수경시설이 추가된 조경공간을 조성하였다. 피험자에게 스트레스를 부여하고, 각각의 공간에서 휴식을 취하게 한 뒤 생리 및 심리적 변화를 비교한 결과, 수경시설이 설치된 조경공간에서 휴식을 취했을 때가 수축기 확장기 혈압이 유의하게 낮아졌다. SD법에 의한 의미평가에서도 수경시설이 설치된 공간이 '활기'와 '동적임', '생명력'과 '유쾌함' 등과 같은 긍정적인 의미를 주는 것으로 나타났으며, POMS(Profile of Mood States)에서는 수경요소가 심리적으로 피로 감소 및 활력 증강에 기여하였다. 이를 통해 실내조경에서 수경시설의 도입은 혈압 감소라는 생리적 변화에 기여하며, 심리 및 기분변화에도 긍정적인 효과를 보임으로써 건강에 편익을 주는 것으로 나타났다.

• 대한두경부종양학회지
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• 제35권2호
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• pp.35-38
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• 2019

Oncocytic lipoadenoma is a rare salivary gland tumor composed of adipose tissue and oncocytic epithelial cells in varied proportions. We report a case of an oncocytic lipoadenoma of the submandibular gland, which presented as a submandibular gland mass. The patient was a 65-year-old woman with a right submandibular mass measuring 2 × 2 × 1.6 cm. As a sonographic evaluation and computed tomograph scan gave us the impression of benign submandibular gland tumor such as pleomorphic adenoma, we resected the right side submandibular gland. Grossly, the tumor was well circumscribed with yellow to brown cut surface. Microscopically, the tumor was surrounded by a thin, fibrous capsule and composed of oncocytic epithelial cells admixed with mature adipose tissue. Final diagnosis was an oncocytic lipoadenoma. We discussed here radiologic and pathologic finding of this rare salivary gland tumor.

• 한국콘텐츠학회논문지
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• 제12권2호
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• pp.182-195
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• 2012

사진은 다양한 목적으로 활용되지만 특히 설득의 도구로 큰 역할을 한다. 사진은 실제를 재현하는 매체라는 독특한 특성 때문에 비교적 설득이 용이하다. 본 논문은 의사 결정에 있어 중요한 역할을 하는 감성을 사진이라는 매체에 대입하여 설득의 역할을 강화하는데 그 목적이 있다. 이를 위해 사진 이미지의 감성구조를 파악하여 긍정적인 감성을 유발하는 요인을 구체적으로 도출하고자 하였다. 특히 사진 이미지의 감성을 구성하는 여러 가지 요인들에 내포적 의미를 부여하고 다양한 요인에 대해 우선순위를 정하여 서열화하는 연구를 수행하여 연구 결과에 대한 실질적인 활용도를 높일 수 있도록 하였다. 사진의 감성은 다양한 원인에 따라 다르게 인지되는데, 사진을 촬영한 대상과 사진을 구성하고 있는 구체적인 화질 속성의 영향이 크다. 따라서 본 논문에서는 다양한 촬영 대상과 화질 속성을 갖는 이미지를 실험 자극으로 활용하여 보다 범용적이고 구체적인 결과를 얻을 수 있도록 하였다.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.120-130
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• 1994

The purpose of the present investigation was to compare the effectiveness of porous hydroxyapatite (PHA) and coralline based porous calcium carbonate(PCC) as implant materials in human periodontal osseous defects. 10 adult patients having periodontitis and 2 similar angular osseous defects ${\ge}$5mm as verified by radiographic analysis and clinical probing depth ${\ge}$4mm were selected. The measurements were recorded just before surgery and after 6 month. Clinical parameters used in this study included gingival recession, pocket depth, probing attachment level, Sulcus Bleeding Index, Plaque Index, tooth mobility and bone defect depth measurements. After initial therapy, patients were treated with mucoperiosteal flap surgery. The contralateral bony defects in each patient randomly assigned to either bone graft material, one with PHA(Interpore 200) and the other with coralline based calcium carbonate(Biocoral). After 6 month both groups showed statistically significant reduction of pocket depth, Sulcus Bleeding Index, Plaque Index and significant improvement in probing attachment level. No statistically significant differences were found between the groups. There were 3.0mm or 68% of bone repair with PHA and 3.1mm, 61% with PCC. These values were likewise not significantly different. The data and clinical impression strongly suggest that both PHA and PCC are alloplastic implants with clinically apparent acceptance by the soft and hard tissue and that they can be used as bone graft materials successfully.

• The Journal of Advanced Prosthodontics
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• 제6권6호
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• pp.468-473
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• 2014

PURPOSE. This study aimed to evaluate the accuracy of digitizing dental impressions of abutment teeth using a white light scanner and to compare the findings among teeth types. MATERIALS AND METHODS. To assess precision, impressions of the canine, premolar, and molar prepared to receive all-ceramic crowns were repeatedly scanned to obtain five sets of 3-D data (STL files). Point clouds were compared and error sizes were measured (n=10 per type). Next, to evaluate trueness, impressions of teeth were rotated by $10^{\circ}-20^{\circ}$ and scanned. The obtained data were compared with the first set of data for precision assessment, and the error sizes were measured (n=5 per type). The Kruskal-Wallis test was performed to evaluate precision and trueness among three teeth types, and post-hoc comparisons were performed using the Mann-Whitney U test with Bonferroni correction (${\alpha}=.05$). RESULTS. Precision discrepancies for the canine, premolar, and molar were $3.7{\mu}m$, $3.2{\mu}m$, and $7.3{\mu}m$, respectively, indicating the poorest precision for the molar (P<.001). Trueness discrepancies for teeth types were $6.2{\mu}m$, $11.2{\mu}m$, and $21.8{\mu}m$, respectively, indicating the poorest trueness for the molar (P=.007). CONCLUSION. In respect to accuracy the molar showed the largest discrepancies compared with the canine and premolar. Digitizing of dental impressions of abutment teeth using a white light scanner was assessed to be a highly accurate method and provided discrepancy values in a clinically acceptable range. Further study is needed to improve digitizing performance of white light scanning in axial wall.

• 한국임상수의학회지
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• 제29권2호
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• pp.173-176
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• 2012

6 년령의 수컷 시츄 견이 복부 팽만을 주 호소로 내원하였다. 복부 방사선 검사와 초음파 검사에서 많은 양의 액체를 포함하고 있는 연부조직 밀도의 종괴가 발견되었다. 종괴의 세포학적 검사를 위해 초음파 유도 세침흡인을 실시하였으며, 세포학적 검사 결과 섬유화가 동반된 육아조직이 의심되었다. 종괴의 확인과 수술적 제거를 위해 진단적 개복술을 실시하였다. 개복시 원위 공장부위에 인접한 장간막의 뿌리에서 유래한 종괴가 확인되었고 종괴는 원위공장 부위에 부착되어 있었다. 종괴와 부착 부위의 분리가 어려웠기 때문에 종괴와 부착 부위를 모두 수술적으로 제거하였으며 장문합술을 실시하였다. 종괴의 조직병리학적 검사 결과 저 악성도 점액육종이 진단되었으며, 종양 세포는 알시안 블루 염색에 양성 반응을 보였다. 추가로 실시한 Ki67 항체를 이용한 면역조직화학 염색 결과 Ki-67 지수는 2.5 였다. 환축은 절제술 실시 후 현재까지 30개월 동안 전이와 재발의 증거 없이 살고 있다.