• The Journal of Advanced Prosthodontics
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• 제8권6호
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• pp.472-478
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• 2016

PURPOSE. The aim of this study was to analyze the shapes of lingual polished surfaces in lower complete dentures formed by polished surface impressions and to provide reference data for use when manufacturing edentulous trays and lower complete dentures. MATERIALS AND METHODS. Twenty-six patients with mandibular edentulism were studied. After lower wax dentures were fabricated, wax was removed from the lingual side of the wax denture and a lingual polished surface impression was obtained with tissue conditioner. The definitive denture was scanned with a three-dimensional scanner, and scanned images were obtained. At the cross-sections of the lingual frenum, lateral incisors, first premolars, first molars, and anterior border of the retromolar pads, three points were marked and eight measurements were taken. The Kruskal-Wallis test and a post hoc analysis with the Mann-Whitney test were performed. RESULTS. Each patient showed similar values for the same areas on the left and right sides without a statistically significant difference. The height of the contour of the lingual polished surface at the lingual frenum was halfway between the occlusal plane and lingual border, it moved gradually in a downward direction. The angle from the occlusal plane to the height of the contour of the lingual polished surface was increased as it progressed from the lingual frenum towards the retromolar pads. CONCLUSION. The shape of the mandibular lingual polished surface was convex at the lingual frenum, lateral incisors and gradually flattened towards the first molars and retromolar pads.

• 대한치과보철학회지
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• 제41권2호
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• pp.243-257
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• 2003

The purpose of this study was to search the influences of the increase of the contents of sodium alginate in the experimental alginates on the some mechanical properties. 3 commercial alginates were selected for the purpose of comparison of the results of experiments. 7 experimental alginates were manufactured with the rise of contents of sodium alginate from 8.8% to 18.3% with the decrease of contents of diatomaceous earth and with the constant contents of calcium sulfate 12.5%. sodium phosphate 2.2%, zinc fluoride 2.0%. Splitable metal mold with 12.5mm diameter and 20.0mm height was filled with mixed alginate to prepare the cylinder shaped specimens. Strain in compression, elastic recovery, compressive strength were tested using the ISO specification number 1563, alginate impression material. Experimental groups were 7, and 10 specimens were used for each test items and each groups. Following results were obtained ; 1. Strain in compression was decreased with the increase of sodium alginate contents (p=0.0077, r2 = 0.6302). 2. Elastic recovery was decreased with the increase of sodium alginate contents but was not significant(p=0.0639, r2=0.7449). 3. Compressive strength was increased with the increase of sodium alginate contents (p<0.0001, r2 = 0.9617). These results mean that the increase of sodium alginate contents make alginate harder but may result the increased permanent deformation.

• The Journal of Advanced Prosthodontics
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• 제13권5호
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• pp.316-326
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• 2021

PURPOSE. Purpose of this in vitro study was to determine the accuracy of different intraoral scans versus laboratory scans of impressions and casts for the digitization of an edentulous maxilla. MATERIALS AND METHODS. A PEEK model of an edentulous maxilla, featuring four hemispheres on the alveolar ridges in region 13, 17, 23 and 27, was industrially digitized to obtain a reference dataset (REF). Intraoral scans using Cerec Primescan AC (PRI) and Cerec AC Omnicam (OMN), as well as conventional impressions (scannable polyvinyl siloxane) were carried out (n = 25). Conventional impressions (E5I) and referring plaster casts were scanned with the inEOS X5 (E5M). All datasets were exported in STL and analyzed (Geomagic Qualify). Linear and angular differences were evaluated by virtually constructed measurement points in the centers of the hemispheres (P13, P17, P23, P27) and lines between the points (P17-P13, P17-P23, P17-P27). Kolmogorov-Smirnov test and Shapiro-Wilk test were performed to test for normal distribution, Kruskal-Wallis-H test, and Mann-Whitney-U test to detect significant differences in trueness, followed by 2-sample Kolmogorov-Smirnov test to detect significant differences in precision (P < .008). RESULTS. Group PRI showed the highest trueness in linear and angular parameters (P < .001), while group E5I showed the highest precision (P < .001). CONCLUSION. Intraoral scan data obtained using Primescan showed the highest trueness while the indirect digitization of impressions showed the highest precision. To enhance the workflow, indirect digitization of the impression itself appears to be a reasonable technique, as it combines fast access to the digital workflow with the possibility of functional impression of mucosal areas.

• 한국가구학회지
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• 제12권2호
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• pp.61-71
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• 2001

In furniture design, it is very important to choose adequate materials. Transparent materials provide expectations and reveals unique effects unlike others. As transparent materials, glass and acrylic have light and fresh impression from their transparency, and are frequently used in structuring neat space. Despite its good merits, glass is not able to satisfy designers desire in making various shape and structure. It has defect in manufacturing process because it requires professional, specialized studio. Compared to glass, acrylic has its merit in processing and stability, and also is very economical. Acrylic is easily used with woodworking tool. In addition, acrylic has unique texture. This study is on the attempt to apply acrylic to the furniture as artistic element.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.268-271
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• 2010

In this paper, forward and reverse analysis is introduced in order to estimate the elastic-plastic properties from a power-law hardening bulk specimen materials with one simple spherical indentation impression test. In order to verify the reliability of the reverse analysis, we have simulated about a large range of materials that essentially cover all engineering materials, using ABAQUS(6.91) program. Then, we could obtained the fitting functions and plastic parameters from the numerical analysis results. Next, through the procedure of reverse analysis we can obtain the yield stress and power-law exponent. Finally, obtain good agreement between the result from reverse analysis and initial input data from experiment.

• 한국의류학회지
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• 제21권6호
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• pp.1060-1071
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• 1997

The purpose of this study is to identify the effect of clothing cues(sleeve and skirt width, length) on female impressions. The experimental materials developed for this study are a set of stimuli and response scales. The stimuli are 16 pictures manipulated with sleeve and skirt width · length variations by computer drawing. The experimental design consists of 3 factorial design: (1) sleeve shapes(plain, upper expanded, below expanded, all expanded) (2) skirt width (wide, narrow) (3) skirt length(long, short) The 7-point semantic differential response scale designed for visual evaluation of female' s impression formation on sleeve shape and skirt width · length is 27 bipolar adjectives. The results of this study are as follows: 1. When we analize the impressions of female figure by sleeve shape and width · length of skirt, it becomes clear that maturity, modernity, attention, elegance and tenderness are proved to be important. Among these five factors, maturity, modernity and attention are identified as more important ones. 2. Sleeve shape have an effect on all factors except maturity and the effects of sleeve on the four factors are not striking. ' Width of skirt are most influential to the maturity and attention, but it does not have any effect on modernity. However two factor, that is width of skirt and sleeve have an effects on modernity, attention and tenderness. ' The length of skirt has an effects on the tenderness, elegance and modernity, but it dose not have any effect on attention. But width and length of skirt have an effects on attention, tenderness and modernity The length of skirt and sleeve have an effect on tenderness.

• 구강회복응용과학지
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• 제22권4호
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• pp.317-328
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• 2006

Purpose: This study was performed to measure the accuracy of adjustable dental impression trays by a scanning laser three-dimensional digitizer. Materials and Methods: Metal stock tray and adjustable stock trays were used for 40 stone casts(10 casts each) duplicated a resin master model of mandible and maxilla. The type IV dental stone was poured in a allginate impressions and allowed to set for one hour. The casts were digitized using an optical digitizer. The distance between the reference points were measured and analyzed on the graphic image of 3-D graphic software (CATIA version 5.0). The statistical significance of the differences between the groups was determined by a two-way ANOVA. Results: There were no significant differences between the accuracies of the adjustable stock tray and the master model except anterior arch width of the upper arch and the diagonal arch length and arch length(one side) of the lower arch. Conclusion: The adjustable stock trays showed clinically acceptable accuracies of the study casts produced by them.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3483-3486
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• 2014

Background: To evaluate the overtreatment rate with the see and treat approach in the management of women with abnormal cervical cytology. Materials and Methods: A retrospective review of patients with abnormal cervical cytology who underwent S&T at MSMC between January 2008 and December 2012 was conducted. Loop electrosurgical excision procedure (LEEP), histological results, cytology and colposcopic impression were analyzed to evaluate overtreatment rate, cyto-histologic correlation and related factors. Results: Average age of S&T cases was 42 years. Ninety seven percents were referred from affiliated health care providers. The study revealed 83.2% patients had HSIL or higher from cervical cytology. Correlation between HSIL and final histology was relatively low at 75% compared to other studies. Overtreatment rate was 28%. Conclusions: S&T was done in 197 patients in a tertiary care health facility with patient satisfaction. Overtreatment occurred, but the rate can be reduced with appropriate recommendations. HSIL Pap smears should be reexamined before S&T while low grade and lesser colposcopic impression groups should obtain conventional colposcopic approach for patient future reproductive benefit.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.483-496
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• 1993

Dentin hypersensitivity medicaments such as Gluma, Scotchbond 2, All-Bond 2, which are resin adhesives, were used to compare the sealing effects of dentinal tubule under mechanical stress. Topical application of above medicaments on the dentin surfaces of extracted teeth followed by artificial tooth brushing for 6 weeks was performed for the comparison. The following conclusions on the degree of dentinal tubule exposure versus time by were reached by using polyvinyl siloxane impression material for taking the impression, epoxy resin for the duplication and SEM for observing the surface. 1. SEM was used to compare the accuracy of the duplicated surface, but no differences were found when teeth samples and the duplicated surfaces were observed. 2. After comparing the degree of dentinal tubules exposure with varnish applied contrast group, resin adhesive materials showed much less exposure as time went by. 3. The results indicated that AU-Bond 2 adhesive, under mechanical stress, showed lesser exposure of dentinal tubules comparing with Gluma and Scotchbond 2 adhesives After the results were put together, it was demonstrated that resin replica method is an useful way to evaluate the treatment effects of the dentinal tubule hypersensitivity medicaments. Also, it was noticed that under mechanical stress, All-Bond 2, classified as fourth generation, illustrated the best dentinal tubules sealing effects.

• 한국의류학회지
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• 제27권3_4호
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• pp.395-406
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• 2003

The Purpose of this study is to find out the effect of clothing style and color, tone combination on impressions formation. The experimental materials developed for this study are a set of stimuli and response scale(The 7-point semantic). The stimuli are 36pictures manipulated with clothing style, color and tone variation by computer drawing. The subjects are 216 female undergraduate students and 216 female of middle age(40~50) in Chin-ji city. The resulte of this study are as follows : Impression factor of the stimulus was consisted of the 5 different demensions(attractiveness, elegance, activity, revealation, tenderness). Among there, attractiveness and elegance factors proved to be more important. In the attractiveness and tenderness, clothing style, color, tone combinations and perceiver's age had the significant effect. In the elegance and revealation, color and perceiver's age had the significant effect but in the activity, only color did not have the significant effect. Significant interaction effects of clothing style and color, style and tone combination, and color and perceiver's age on attractiveness and revealation were found. Interaction effect of color and tone combination was significant on the elegance and revealation, and that of color and perceiver's age was significant on tenderness.