• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.850-868
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• 1996

The accuracy and dimensional stability of impression materials are one of the most important factors for successful prosthodontic treatment. The purpose of this study was to evaluate the accuracy of several dental elastomeric impression materials used widely and clinically : Impregum-$F^{(R)},\;Permlastic^{(R)},\;Silascon^{(R)},\;Perfect^{(R)},\;Xantopren^{(R)}$. There have been many studies to evaluate the accuracy of impression materials. But it has not been decided yet, which method was most suitable for the evaluation of the accuracy. In this study, two resin teeth, #15 & 25, were prepared with rounded shoulder margin and 90 degree cavosurface angle. For the polysulfide rubber and polyether, the custom tray was made at least 24 hours prior to impression taking. For the silicone rubber materials, putty/wash impression technique was applied in taking impressions. Marginal openings of the castings on the master dies and prepared resin teeth were measured under stereomicroscope. The results were statistically analyzed and compared between tested impression materials. The results were as follows ; 1. In the overall accuracy of impression materials, polyether was the most accurate one, followed by polysulfide, additional silicone and condensation silicone. 2. On the first model pouring, condensation silicone had the largest discrepancies and there was significant difference compared to the other impression materials. 3. Polysulfide had the least discrepancies in the first model pouring, but showed larger discrepancies in the immediate second pouring than the first pouring. 4. On the immediate second pouring, the discrepancy of polyether was shown to be the smallest, while the largest one was additional silicone. 5. Polyether and polysulfide rubber using custom impression trays showed superior accuracy to silicone rubber, putty/wash impression technique.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.703-708
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• 2009

The present paper describes the application of an improved impression transfer vector method (Sakurai et al., 2007) to transform the three basic dimensions (Evaluation, Activity, and Potency) of higher-order impression. First, a set of shapes and surface textures of faces was represented by multi-dimensional vectors. Second, the variation among faces was coded in reduced parameters derived by applying principal component analysis. Third, a facial attribute along a given impression dimension was analyzed to select discriminative parameters from among principal components with higher sensitivity to impressions, and obtain an impression transfer vector. Finally, the parametric coordinates were changed by adding or subtracting the impression transfer vector and the image was manipulated so that its facial appearance clearly exhibits the transformed impression. A psychological rating experiment confirmed that the impression transfer vector modulated three dimensions of higher-order impression. We discussed the versatility of the impression transfer vector method.

• The Research Journal of the Costume Culture
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• v.7 no.1
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• pp.117-127
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• 1999

Clothes are a kind of silent language that tells someone who has in wear and has great influence on person perception and impression formation. Present paper aims, therefore, to investigate the tendency of its study to offer information that my assist future studies. Doctorial dissertations, master\`s theses and journal articles related with clothing and textiles in domestic are categorized according to period and subject. Analysed results are as follows: First, as for the periodic vicissitude, the number of study on impression formation was before 1990, but tend to increase in 1990\`s. Second, as for the subject, while the studies focused on impression formation wearer on the first half of 1990\`s, they were segmented and presented wearer\`s form and appearance in detail ; computer simulation was also made use of in various papers. In conclusion, impression formation seems to become a rather important subject for further study.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.7
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• pp.995-1006
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• 2004

This study examines the effects of clothing style and the order effect on impression formation. The instrument of this study consisted of response scales and stimuli. Fifty-one items of 7-point semantic differential scales, 9 items of demographic traits, and 4 items of subjective evaluation scales were developed. Stimuli were color pictures of a model wearing each of two clothing styles(mannish style, feminine style). The sample include 56 male and female subjects in their twenties and thirties. The experimental design was within-subject design and the half of the sample responded to the mannish style first and the other half responded to the feminine style first. Responses to the semantic differential scales were factor analyzed, and seven factors were identified: intellectuality, sensibility, activity, modesty, competence, display, keenness. There were significant differences between mannish style and feminine style in impression of wearer＇s age, job, and physical attractiveness as well as wearer＇s intellectuality and sensibility. It was revealed that the first impression and second impression of wearer＇s intellectuality, sensibility, modesty, competence, display were differed by the function of the order of stimuli shown to the subjects. Both primacy effect and recency effect of order effect were confirmed, and especially negativity effect was influenced prominently on impression formation.

• The Journal of Advanced Prosthodontics
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• v.10 no.4
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• pp.265-270
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• 2018

PURPOSE. The purpose of this in vitro study was to evaluate the accuracy of a new implant impression technique using bite impression coping and a dual arch tray. MATERIALS AND METHODS. Two implant fixtures were placed on maxillary left second premolar and first molar area in dentoform model. The model with two fixtures was used as the reference. The impression was divided into 2 groups, n=10 each. In group 1, heavy/light body silicone impression was made with pick up impression copings and open tray. In group 2, putty/light body silicone impression was made with bite impression copings and dual arch tray. The reference model and the master casts with implant scan bodies were scanned by a laboratory scanner. Surface tessellation language (STL) datasets from test groups was superimposed with STL dataset of reference model using inspection software. The three-dimensional deviation between the reference model and impression models was calculated and illustrated as a color-map. Data was analyzed by independent samples T-test of variance at ${\alpha}=.05$. RESULTS. The mean 3D implant deviations of pick up impression group (group 1) and dual arch impression group (group 2) were 0.029 mm and 0.034 mm, respectively. The difference in 3D deviations between groups 1 and 2 was not statistically significant (P=.075). CONCLUSION. Within limitations of this study, the accuracy of implant impression using a bite impression coping and dual arch tray is comparable to that of conventional pick-up impression.

• The Journal of Advanced Prosthodontics
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• v.10 no.5
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• pp.335-339
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• 2018

PURPOSE. The purpose of the present study was to compare scanning trueness and precision between an abutment impression and a stone model according to dental computer-aided design/computer-aided manufacturing (CAD/CAM) evaluation standards. MATERIALS AND METHODS. To evaluate trueness, the abutment impression and stone model were scanned to obtain the first 3-dimensional (3-D) stereolithography (STL) file. Next, the abutment impression or stone model was removed from the scanner and re-fixed on the table; scanning was then repeated so that 11 files were obtained for each scan type. To evaluate precision, the abutment impression or stone model was scanned to obtain the first 3-D STL file. Without moving it, scanning was performed 10 more times, so that 11 files were obtained for each scan type. By superimposing the first scanned STL file onto the other STL files one by one, 10 color-difference maps and reports were obtained; i.e., 10 experimental scans per type. The independent t-test was used to compare root mean square (RMS) data between the groups (${\alpha}=.05$). RESULTS. The $RMS{\pm}SD$ values of scanning trueness of the abutment impression and stone model were $22.4{\pm}4.4$ and $17.4{\pm}3.5{\mu}m$, respectively (P<.012). The $RMS{\pm}SD$ values of scanning precision of the abutment impression and stone model were $16.4{\pm}2.9$ and $14.6{\pm}1.6{\mu}m$, respectively (P=.108). CONCLUSION. There was a significant difference in scanning trueness between the abutment impression and stone model, as evaluated according to dental CAD/CAM standards. However, all scans showed high trueness and precision.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.817-827
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• 2001

This study tried to investigate whether characteristics of the perceiver and image of ideal woman made differences in the important factors for the selection clothing and the preference of clothing. A poll of 650 men & women between the ages of 20-39 living in Daegu was taken for this study. Factor analysis, cluster analysis, frequency, ANOVA-test, t-test, and $\chi$$^2$-test were implemented with the SPSS-package. The characteristics of clothing types used in this study included: sexy, masculine, feminine, dramatic, elegant-classic, and casual. The results were as follows. 1. In the situation of first impression formation, the characteristics of the perceiver made differences in the selection of clothing types. Women took self-satisfaction and fashion factors to be more important than men, so did persons in their 20s than 30s. And the unmarried took self-satisfaction factor to be more important than the married. 2. Men and women had different images of the ideal woman. Under special situations of first impression formation, such as, formal blind dates on the condition of marriage and casual blind dates, there were differences in clothing preference.

• Journal of the Korean Society of Clothing and Textiles
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• v.6 no.1
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• pp.27-38
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• 1982

The purpose of this research was to find out the effects of the person and costume on the formation of first impression. 4 Models were choosen who had sporty, intellectual, social and cute impression. Tried on them sporty, intellectual, social and cute costumes, 16 pictures of them were taken four ty four method, and those were shown to 640 college girl students in Seoul to check the change of impression. The results are as follows : 1) The sporty costume to he perceived as sporty than either the social or intellectual and cute costume. 2) The social person to he perceived as social than either the sporty on intellectual and cute person. 3) The intellectual costume to be perceived as intellectual than either the sporty or social & cute costume. 4) The cute costume to be perceived as cute than either the sporty or social and intellectual costume.

• Journal of Dental Rehabilitation and Applied Science
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• v.21 no.1
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• pp.83-93
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• 2005

This study was designed to investigate the fitness of adjustable dental impression trays. The size and shape of these trays were designed from the results of the dental arch size of Korean adults. Tray samples were made by CAD-CAM working. A hundred dental students(male:50, female:50) were selected for taking irreversible hydrocolloid impression using these trays. The author measured the width and length of impression material on the several measuring points. The results obtained were as follows : 1. Uniform impression material thickness was achieved by controlling the width of the tray using stops and beveled guides. 2. In the upper tray, the impression material thickness was measured to be rather great showing thickness of the labial vestibule 8.3 mm and the midpalatal part 8.6 mm. 3. In the lower tray, length of the impression material of the labial vestibule of first, second premolar contact point was 7.8 mm, and thickness of the lingual part of premolars(1.8 mm) and molars(1.9 mm) showed small values. 4. In the lower tray, the impression material thickness of the buccal shelf area(0.2 mm) and the retromolar pad area(0.6 mm) was measured to be too small.

• The Journal of Advanced Prosthodontics
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• v.3 no.1
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• pp.33-36
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• 2011

In process of fabrication of a fixed partial denture, dies are trimmed to expose margins of the preparations. The need for the soft tissue cast is quite evident as the soft tissue emergence profile that surrounds the prepared tooth is destroyed in the process of fabrication. This article describes a modified technique to fabricate the soft tissue cast for the conventional fixed partial denture. The impression made with the polyvinylsiloxane was first poured to prepare the die cast. After retrieval of the cast, the same impression was poured second time with the resin based resilient material to cover the facial and proximal gingival areas. The remaining portion of the impression was poured with the gypsum material. This technique does not require additional clinical appointment, second impression procedure, technique sensitive manipulations with impression, or cumbersome laboratory procedures. The simplicity of this technique facilitates and justifies its routine use in fabrication of the fixed partial denture.