• The Journal of Korean Academy of Prosthodontics
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• v.56 no.3
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• pp.206-211
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• 2018

Purpose: Recently, a method of forming a slot in the prosthesis lingual has been introduced to solve the occlusal and aesthetic disadvantages of screw-retained prosthesis in the manufacture of implant-fixed prosthesis and to ensure retrievability in cement retained prostheses. The purpose of this study is to investigate the effect of the internal gap on the removal of the prosthesis in the preparation of cement-retained implant prostheses with lingual slots. Materials and methods: Titanium abutment and internal gap of the zirconia prosthesis to be attached to the upper part were set to 30, 35, and $50{\mu}m$, respectively. Three for each type total 15 were produced for each type. The zirconia prosthesis formed a retrievable cement-type slot with a space of 1 mm at the location where the titanium abutment meets the shelf area. Autocatalytic resin cement was used for bonding of abutment and zirconia prosthesis, and the maximum removal stress value was measured in units of Ncm by using the customized equipment of the cemented specimen. The Kruskal-Wallis test was used to compare the three groups by statistical analysis (${\alpha}=.05$), modified by post hoc test the Mann-Whitney U-test and the Bonferroni correction method were used to compare the two methods (${\alpha}=.017$). Results: There was no statistically significant difference in removal stress between the $30{\mu}m$ group and the $35{\mu}m$ group in the internal gap (P = .032), and there was a significant difference between the $30{\mu}m$ group and the $50{\mu}m$ group, between the $35{\mu}m$ group and the $50{\mu}m$ group (P < .017). Conclusion: Thus, the internal gap of computer-aided design affected the retention between the zirconia prosthesis and the titanium abutment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1560-1570
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• 2007

The purpose of this study was to investigate the differences according to lifestyle in anthropometric measurement, dietary attitude, health-related behaviors and nutrient intake among the college students. The subjects were 994 nation-wide college students (male: 385, female: 609) and divided into 7 clusters (PEAO: passive economy/appearance-oriented type, NCPR: non-consumption/pursuit of relationship type, PTA: pursuit of traditional actuality type, PAT: pursuit of active health type, UO: utility-oriented type, POF: pursuit of open fashion type, PFR: pursuit of family relations type). A cross-sectional survey was conducted using a self administered questionnaire, and the data were collected via Internet or by mail. The nutrient intake data collected from food record were analyzed by the Computer Aided Nutritional Analysis Program. Data were analyzed by a SPSS 12.0 program. Average age of male and female college students were 23.7 years and 21.6 years, respectively. Most of the college students had poor eating habits. In particular, about 60% of the PEAO group has irregularity in meal time. The students in PAH and POF groups showed significantly higher consumption frequency of fruits, meat products and foods cooked with oil compared to the other groups. As for exercise, drinking and smoking, there were significant differences between PAH and the other groups. Asked for the reason for body weight control, 16.2% of NCPR group answered "for health", but 24.8% of PEAO group and 26.3% of POF group answered "for appearance". Calorie, vitamin A, vitamin $B_2$, calcium and iron intakes of all the groups were lower than the Korean DRIs. Female students in PTA group showed significantly lower vitamin $B_1$ and niacin intakes compared to the PFR group. Therefore, these results provide nation-wide information on health-related behaviors and nutrient intake according to lifestyles among Korean college students.