• The Journal of Korean Academy of Prosthodontics
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• v.42 no.4
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• pp.443-457
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• 2004

Purpose: The purpose of this study was to analyze and estimate whether each company may produce the color of artificial teeth as it stands, in the standard of vita classical shade guide using ShadeScan$^{TM}$ System. Material and methods: we chose the products of 6 companies -EFUCERA, IVOCLAR, ENDURA, TRUBYTE, DURADENT, and DURACROSS- estimated the shade value of each fixed point(cervical, body, and incisal area) of artificial tooth, and verified the equality among the samples from the same company. Results: First, the variation appeared significant at cervical and incisal area. It means that there were significant differences between cervical and incisal area although the most similar artificial teeth to the patients’natural teeth were provided. Second, the results in the body area showed that the variation between artificial and natural teeth was finite(p<0.05) in that area. Conclusion: it shows that the reproduction of colors of artificial teeth might be successful regarding the body is the most important part for a determination of the color of artificial teeth. However, more complements are necessary for the better reproduction of the color of artificial teeth between cervical and incisal area.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.41.1-41.7
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• 2020

Objectives: This study aimed to evaluate the ability of lithium disilicate ceramics to reproduce the A2 shade and to mask A4 substrates. Materials and Methods: Twenty-four discs (8 mm in diameter, shade A2) of high translucency (groups 1-3) and low translucency (groups 4-6) of IPS e.max ceramic with different thicknesses (0.5, 0.75, and 1 mm) were fabricated as monolithic structures. In addition, discs of medium opacity (group 7-8) with different core/veneer combinations (0.3 mm/0.7 mm and 0.5 mm/0.5 mm) were fabricated as bilayer structures. Specimens were superimposed on an A4 substrate (complex). The color changes of the complex were measured using a spectrophotometer on a black background, and the ΔE values of the complex were compared with either the A4 substrate or the A2 shade tab. One-way analysis of variance, the Tukey honest significant difference test, and the Fisher test were used to analyze the data (p < 0.05). Results: Significant between-group differences were found for comparisons to both the A4 substrate and the A2 shade (p < 0.05). When compared with the A4 substrate, the ΔE values in all groups were in the non-acceptable range. When compared with the A2 shade, the ΔE values in all groups, except groups 2 and 3, were in the clinically acceptable range. Conclusions: All translucencies and thicknesses masked the underlying dark substrate. However, the low-translucency IPS e.max Press better reproduced the A2 shade.

• The Journal of the Korea Contents Association
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• v.14 no.2
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• pp.84-93
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• 2014

Comics uses words to convey its content and meaning, while the comic image conveys the content as a narrative function to represent how language is combined with the text. This paper makes a comparison and analysis of the comics of Japan and South Korea, in terms of words and image expression, narrative techniques, and the way of communication, to study the characteristics of image narrative. The comic image of Jing ke is the other as a flow of narrative and getting rid of the current screen, to resonate with the readers. Go U-yeong's comics and Sumeragi Natsuki's set up a virtual narrative time and space through the line, surface, space and shade, to realize the reproduction of unhistorical facts and the significance of narrative with the artist's imagination. Sumeragi Natsuki's comics uses historical facts to represent exquisite narrative like still-life paintings. She focuses on the description of the objective facts of history, to seek the sensitive comic image beyond reality. The image narration of Go U-yeong's comics is a clash between his historical narrative among the subjective romantic image and the readers' awareness narrative flow that they insist inside. Therefore, he tries to keep balance. The instant image in his comics is not a reproduction of the historical real moment, but a reproduction image of the reality reconstructed by his own pursuit of narrative.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.100-105
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• 2020

Northern pipevine (Aristolochia contorta) commonly inhabits marginal areas between waterside and terrestrial vegetation. In particular, A. contorta is ecologically important in the marginal areas as a food plant of dragon swallowtail butterfly (Sericinus montela), which is designated as vulnerable species in the Republic of Korea. For long-term sustainability of the plant population, assessment of the genetic diversity of exist populations should be conducted. Genomic DNA of A. contorta leaf samples were extracted from four populations where the vigorous growth were observed in the South Korea. Intra-population genetic diversity and inter-population genetic distance were assessed using randomly amplified polymorphic DNA (RAPD) with five polymorphic random primers. Overall genetic diversity was lower, compared to other wetland species (h: 0.0607 ~ 0.1401; I: 0.0819 ~ 0.1759), while GP showed the highest intra-population genetic diversity. Despite of the geographical distance, GP showed the larger genetic distance from other populations. This result seemed to be caused by the fragmented habitat and lower sexual reproduction of A. controta. Mixture of the different source populations and construction of the proper environmental condition such as shade and physical support for sexual reproduction should be considered for conservation of A. contorta population.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.99-105
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• 2005

We investigated oviposition and colony development of Bombus ignitus and B. terrestris depending on different pollen. In five kinds of pollen blend, the colony development in fresh-freezing pollen blend produced in Korea (Korea-FFP) was the best performance, although egg-laying characteristics is lower than that of pollen blend for oviposition imported from Korppert company (Kopport-FOP). The Kopport-FOP proved that it was suitable to use for oviposition of bumblebees. The Korea-FFDP, freezing dried-fresh pollen blend produced in Korea, is lower rather than the Korea-FDP although it is similar to the KopportFOP in colony development. It is not efficient to use commercial pollen for bumblebee because it is expensive in cost. The dried pollen blend for honeybee feeding imported from China (China-DP) was not suitable for rearing of bumblebee because it did not form colony although the worker emerged. In types of pollen, the oviposition and colony development of B. ignitus were not affected by the fresh-freezing pollen and dried-freezing pollen. This result also indicated that dried pollen, dried in the shade for 5 - 6 days, is possible to use as commercial pollen for bumblebee reproduction.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.3
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• pp.262-275
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• 2015

The treatment of areas demanding esthetic requirements, such as maxillary anterior teeth, should take into account the achievement of a healthy, harmonious to the surrounding tissue, and an attractive smile line. In this case report, smile line, soft tissue and hard tissue morphology, and the anatomy and proportion of the tooth, must be considered. In patients with unesthetic maxillary anterior ratio due to inadequate gingival contour and diastema caused by peg lateralis, it would be challenging to achieve an esthetic restoration by orthodontic treatment alone. In such case, after orthodontic treatment, dento-gingivo-facial compositional diagnosis and analysis, followed by gingivectomy and prosthodontic restoration is needed to improve the interdental mesial/distal, width/length ratio to achieve a satisfactory esthetic result. In addition, when improving the tooth proportion of peg lateralis by prosthodontic treatment, Porcelain laminate veneer (PLV), which results in less tooth structure loss, reproduction of similar shade to that of the proximal tooth and high transparency, is recommended. This case report demonstrates esthetic improvements by prosthodontic restoration through systematic diagnosis and treatment procedure in patients with unesthetic maxillary anterior proportion after orthodontic treatment due to peg lateralis by means of two female patients aged twenty years old.