• Journal of the Korean Academy of Esthetic Dentistry
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• v.4 no.1
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• pp.23-36
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• 1995

The purpose of this artic1e is to compare soft tissue profiles between Korean adults with normal occ1usion and malocclusin and to identify the differences between them. The subjects of this cephalometric study were 40 males with normal occlusion(Group 1), 27 females with normal occlusion(Group 2), 28 adults with Angle's Class II malocclusion(Group 3) and 41 adults with Angle's Class III malocclusion(Group 4). The results of this study were as follows ; 1) People with Angle's Class II malocclusion had tendency to have more labial tipping of lower teeth than people with normal occ1usion. Through NOA angle measurement, it was determined that people with Angle's Class II malocclusion had more protruding midface than people with normal occlusion and people with Angle's Class III malocclusion had retruding midface. 2) Through Powell's esthetic triangle analysis, it was determined that people with Angle's Class II malocclusion had retruding chin and protruding nose. 3) No significant differences between people with normal occlusion and maloclusion could be identified by measuring soft tissue profile angle basis of S-NS plane. 4) There were significant differences between groups with normal occlusion and malocclusion by measuring Facial convexity angle(Significance level 99%). 5) By measuring the distance between each landmark basis of N-Pog plane, People with Angle's Class II malocclusion were identified as having more protruding midface, but there were no significant differences between people with normal occlusion and Angle's Class III malocclusion. 6) By measuring the vertical dimension of the face, it was determined that the lower facial height was higher than the upper facial height in all groups, particularly in group with Angle's Class III malocclusion. 7) By measuring the lips basis of E-line and S-line, it was determined that people with Angle's Class III malocclusion had more, protruding lower lips than people with normal occlusion, while people with normal occlusion, while people with Angle's Class II malocclusion had more protruding upper lips. By measuring the distance between the superior sulcus and inferior sulcus basis of H-line, people with Angle's Class II malocclusion had thicker upper lips than the other's.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.218-233
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• 2013

This study used SPSSS 18.0 on 237 university students in Busan for frequency, factorial and reliability, correlation, and regression analyses to determine the effect relationship of coffee shop service quality on perceived value and behavioral intention. Multiple regression analysis for hypothesis testing showed that among the four service quality factors, confidence in employees and primary coffee quality had a non-significant effect on esthetic value, while menu characteristics besides coffee (${\beta}$=.293, p<.001) and physical environment (${\beta}$=.293, p<.001) were analyzed to be significant, partially supporting the study hypothesis. Regarding the effect of service quality on practical value, confidence in employees (${\beta}$=.264 p<.001), primary coffee quality (${\beta}$=.463, p<.001), menu characteristics besides coffee (${\beta}$=.139, p<.05) and physical environment (${\beta}$=.110, p<.05) were all significantly analyzed, supporting the study hypothesis. Regarding the effect of service quality on behavioral intention, confidence in employees (${\beta}$=.262 p<.001), primary coffee quality (${\beta}$=.411, p<.001), menu characteristics besides coffee (${\beta}$=.157, p<.01) and physical environment (${\beta}$=.137, p<.05) were all significantly analyzed, supporting the study hypothesis. In addition, regarding the effect of perceived value on behavioral intention, esthetic value (${\beta}$=.265, p<.001) and practical value (${\beta}$=.536, p<.001) were both significantly analyzed, showing a causal relationship with behavioral intention.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.174-181
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• 2009

Statement of problem: There is a reduction of dentin bonding strength when the bonding procedure is carried out immediately after bleaching with peroxides. Purpose: The aim of this study is to evaluate a proper time interval for in-office bleaching technique using 35% hydrogen peroxide. Material and methods: Fifty extracted non-caries human third molars were used in this study. Buccal enamel of each tooth was removed and polished by 600 grits silicone carbide paper. They were randomly divided into five groups and bleached 35% hydrogen peroxide except control group. All groups were bonded with Single Bond/Z 350 after each time intervals ; Group-A: control, no bleaching treatment. Group-B: resin bonding immediately after bleaching. Group-C: resin bonding 1day after bleaching. Group-D: resin bonding 2 days after bleaching. Group-E: resin bonding 7days after bleaching. Shear bond strengths were measured with a cross-head speed of 1.0 mm/min using an Instron machine. The data of results were statistically analyzed by analysis of variance(ANOVA) and Tukey multiple comparison test.(P=.05) Results: There were significant decreases in mean shear strength in immediately bonding group after bleaching. The reduction of bond strengths was 78% compared with the group of no bleaching treatment. Group C showed the recovery of 51%, and Group D showed recovery of 63%. Both of them have no statistical difference with non-bleaching group. Group E showed no statistical difference with no bleaching treatment group. Conclusion: Dentin bonding strength is significantly reduced when bonding is performed immediately after bleaching for in-office bleaching regimens using 35% hydrogen peroxide, and increases as time goes by. One week of elapsed time between bleaching and resin bonding significantly increases bonding strengths for the in-office bleaching technique.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.318-327
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• 2019

The purpose of this study was to identify which combination of zirconia crowns and cements is most similar in color to the maxillary primary incisors by varying the color of zirconia crowns, crown thickness, and shade of cements. Prefabricated zirconia crowns in 3 shades and crowns fabricated using 6 types of zirconia blocks were used in this study. These were filled with A2-shade or translucent-shade resin cement and the $L^*$, $a^*$, and $b^*$ values were calculated using a spectrophotometer. The color differences between the natural teeth and the zirconia crowns were assessed. The shade of the final restoration was more similar to that of the natural teeth using A2-shade than translucent-shade resin cement. Application of A2-shade cement to a 0.5-mm-thick crown fabricated from a smile series 2 zirconia block resulted in the color most similar to that of the natural teeth. A2-shade resin cement is recommended for zirconia crown restoration in anterior primary teeth compared to TR-shade resin cement for more esthetic restoration. Since restorations with Nu-smile zirconia crowns were not esthetically favorable in terms of shade, improvement of the shade characteristics of the product or development of a new kind of zirconia crown is required.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.132-140
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• 2010

Purpose: The aim of this study is to identify the usefulness of unilateral mandibular angle ostectomy, so-called "Lateral Angle Reduction", in asymmetric prognathism patients by the assessment of postoperative stability and esthetic results Patients and methods: For the retrospective study, 10 skeletal class III mandibular asymmetry patients who were performed SSRO and unilateral mandibular angle ostectomy, Lateral Angle Reduction, was selected. Lateral and posterioanterior cephalogram was taken before surgery (T0), 1day after surgery (T1) and 6month after surgery (T2). To know the esthetic results the facial width and lateral facial contour were examined on posterioanterior cephalogram and to know the postoperative stability B point and Incisor inferius was examined on lateral cephalogram. Statistical analysis was performed. Results: From T0 to T1, Intergonial width was significantly decreased, dominantly at shortened side but no significant changes at lengthened side. Those were well-maintained during 6 months. Lateral facial angle and Ramus angle was significantly decreased on only shortened side from T0 to T1. As a result, after surgery, there were no significant differences in all measurements between shortened side and lengthened side. Ramus deviation angle in shortened side and ramus angle in lengthened side which reflect the angulation of ramus on frontal plane didn't show significant changes after surgery and during postsurgical periods. Lower dental midline showed no statistical changes during postsurgical period. The relapse rate on B-point was 11.92%. Conclusion: Unilateral "Lateral angle reduction" in the asymmetric mandible is valuable to obtain the narrow lower face and symmetric facial contour with a good stability.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.2
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• pp.171-179
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• 2017

Severely worn dentition is frequently multifactorial. It is crucial that the etiology of excessive wear be determined, but accurately diagnosing the factors responsible for tooth wear is often confusing. Before initiating the treatment of these cases, meticulous examination and determining vertical dimension are essential. A 69-year-old male patient had the chief complaint that he has worn dentition and functional and esthetic discomfort. Based on model analysis and diagnostic wax up, new vertical dimension had been determined. Provisional restorations were cemented and after 5 months permanent prostheses were fabricated. This case reports a satisfactory functional and esthetic clinical outcome achieved by restoring the vertical dimension.

• Journal of the korean academy of Pediatric Dentistry
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• v.5 no.1
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• pp.64-75
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• 1978

In order to know cephalometric norms for the preschool children, this roentgeno cephalometric study was undertaken in each 50 Korean male and female children of primary dentition age from 4 to 5 year. The following results were obtained. 1. In the skeletal analysis, there was no significant difference between male and female in angular measurement and the linear measument of the male was generally greater than that of the female. 2. Saddle angle was $122.3^{\circ}$, articular angle was $147.6^{\circ}$, gonial angle was $119.4^{\circ}$ and the sum of each angle was $396.1^{\circ}$ in male and $396.6^{\circ}$ in female. 3. The ratio of mandibular body to anterior cranial base was about 1 : 0.91. 4. In the primary dentition, suggested that the nasion and point A move forward relative to sella turcica in a fashion, pogonion and point B are equal in angular position relative to plan S-N, bony chin and chin button was yet underdeveloped, and the forward growth of mandible was seen rapid than maxilla after 4 years. 5. Suggested that the percentage of anterior facial height to the posterior facial height were 64.4% in male and 64.1% in female. 6. Maxillary primary incisors was more upright than the permanent incisors, mandibular primary incisors was inclined lingually relative to the permanent incisor, and primary incisors was more upright than the permanent incisors. 7. Maxillary primary incisors in female was inclined labially than male. 8. In the the relationship of the upper lip and lower lip to the esthetic line, the upper lip was 2.11mm and the lower lip was 2.33mm front of the esthetic line.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.427-433
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• 2014

PURPOSE. Surface color is one of the main criteria to obtain an ideal esthetic. Many factors such as the type of the material, surface specifications, number of firings, firing temperature and thickness of the porcelain are all important to provide an unchanged surface color in dental ceramics. The aim of this study was to evaluate the color changes in dental ceramics according to the material type and glazing methods, during the multiple firings. MATERIALS AND METHODS. Three different types of dental ceramics (IPS Classical metal ceramic, Empress Esthetic and Empress 2 ceramics) were used in the study. Porcelains were evaluated under five main groups according to glaze and natural glaze methods. Color changes (${\Delta}E$) and changes in color parameters (${\Delta}L$, ${\Delta}a$, ${\Delta}b$) were determined using colorimeter during the control, the first, third, fifth, and seventh firings. The statistical analysis of the results was performed using ANOVA and Tukey test. RESULTS. The color changes which occurred upon material-method-firing interaction were statistically significant (P<.05). ${\Delta}E$, ${\Delta}L$, ${\Delta}a$ and ${\Delta}b$ values also demonstrated a negative trend. The MC-G group was less affected in terms of color changes compared to other groups. In all-ceramic specimens, the surface color was significantly affected by multiple firings. CONCLUSION. Firing detrimentally affected the structure of the porcelain surface and hence caused fading of the color and prominence of yellow and red characters. Compressible all-ceramics were remarkably affected by repeated firings due to their crystalline structure.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.13 no.1
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• pp.19-24
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• 2004

This study is intended to provide a referable information of exposed amount of maxillary central incisor of Korean by ages and gender under rest position. The result of this study will give guidelines for making prothesis. The subjects of this study are patients of Charmgoun Dental Hospital in Busan, Korea. A statistical analysis was conducted after taking digital photos of patients' teeth with a ruler and measuring the length of teeth on the computer program. The results of this study were as follows : 1. The length of maxillary central incisor that exposed under upper lip is decreased by increasing age in rest position.; the average length is 3.455mm in 20s, 2.525mm in 30s, and 1.543mm in 40s. 2. The exposal length in females is more than males, average length is 2.796mm in female and 2.342mm in male. However, there is not significant difference between the genders. 3. The exposed average length of maxiallry central incisor under upper lip is 2.618mm at rest. 4. The clinical crown average length of maxillary central incisor is 10.195mm, but incresing age, there is no significant defference. 5. There is significant difference between the genders in the clinical crown length of maxillary central incisor.; the length is 10.637mm in men, 9.90mm in women.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.28 no.1
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• pp.54-60
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• 2019

Objective: Dental fear is a feeling of anxiety and fear without intervention during a dental visit, mainly due to past negative dental treatment experiences, and in adults, despite the recognition of the need for dental treatment, it can lead to avoidance of dental treatment, which may cause deterioration of oral health. Therefore, this study was conducted to measure dental fear and anxiety level in some adults, and to identify related factors and their causes. Methods: This study used Kleinknecht's Dental Fear Survey scale and the SPSS 21 program (IBM SPSS Statistics 21) was used for analysis. Result: When the dental fear was the higher, the "access to the dental clinic" was found to be the highest, followed by "sitting in dental unit chair" and "smell of dental clinic" in that order. Conclusions: Dentists and dental hygienists should be able to understand the fear, anxiety, and concerns of the dentist office and to find various ways to provide systematic medical services.