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Purpose: This study was performed fracture strength test by conducted change of abutment and coping shape for suggesting monolithic all ceramic crown which has thin thickness and superior strength of the occlusal surface. Methods: The specimens on the four kinds abutment was made according to thickness of occlusal surface and angle of axis surface. And All ceramic coping specimens of 6 different kinds was made by the CAD/CAM Method. Compression strength test using the UTM and the verification of compression-stress situation using the 3D finite element method were conducted under optimum conditions. Results: 516C specimen was showed the strongest compression-fracture strength, followed by 516FR, 516F45, specimens. Did not show significant differences between 516FR and 516F45. 516C of the universal testing machine the specimen's surface that are within the vertical load is small, finite element method of a uniformly distributed load, so the value received suggests otherwise. Conclusion: In conclusion, abutments of monolithic ziconia ceramic when having a same thickness of the occlusal, as the angle of occlusal edge is small, the stress is well dispersed and it can endure well in the fracture.

Purpose: The purpose of this study was to compare the tensile strength and mechanical properties of orthodontic wire joints made by gas soldering and laser welding, with and without filling material, to identify the effectiveness and potential clinical application of laser welded orthodontic wires. Methods: Three joint configurations of orthodontic wire were used: diameter 0.9 to 0.9 wire, diameter 0.9 to 0.5 wire and diameter 0.9 wire to band. The joints were made using three different methods: gas soldering, laser welding with and without filling material. For each kind of joint configuration or connecting method 7 specimens were carefully produced. The tensile strengths were measured with a universal testing machine (Zwick/Roell, Instron, USA). The hardness measurements were carried out with a hardness tester(Future-Tech Co. Tokyo, Japan). Data were analyzed by AVOVA(p= .05) and Turkey HD test(p= .05). Results: In all cases, gas soldering joints were ruptured on a low level on tensile bonding strength. Significant differences between laser welding and gas soldering(p< .05) were found in each joint configuration. The highest tensile strength means were observed for laser welding, with filling material, of 0.9 to 0.9 wire joint. Conclusion: In conclusion, the elastic modulus and tensile strength means of laser soldering with filling material were the highest, and the tensile strength means of laser soldering were higher than those of gas soldering.

Purpose: The aim of this study was to evaluate the effect of colored zirconia with different coloring liquids. Methods: Total 30 specimens were prepared. Specimens were classified into 6 groups: IPS e.max Ceram(P), Uncolored zirconia(C), VITA In-Ceram 2000 YZ LL1(L), Zirkonzahn coloring liquid(Z), Wieland coloring liquid(W), and Kuwotech coloring liquid(K). Four different types of zirconia coloring liquid, VITA In-Ceram 2000 YZ LL1(VITA Zahnfabrik, Germany), Zirkonzahn coloring liquid(Zirkonzahn, Italy), Wieland coloring liquid(Wieland, Germany), Kuwotech coloring liquid(Kuwotech, Korea) were used to fabricate colored zirconia by using infiltrating method and then completely sintered. The color of the all specimens was measured using the spectrophotometer(CM-2600d, Konica Minolta, Japan) and expressed in terms of the 3-coordinated values (CIE L*a*b*). Color differences were calculated using the equation ΔE*= [(ΔL*)2+(Δa*)2+(Δb*)2]1/2. Results: L*a*b* values of the colored zirconia were affected by the coloring liquids. The uncolored zirconia(C) group showed the highest L* value and zirkonzahn coloring liquid(Z) group showed the lowest L* value. Zirkonzahn coloring liquid(Z) showed the highest a* value and VITA In-Ceram 2000 YZ LL1(L) group showed the highest b* value. Generally, the color difference(ΔE*) in all groups showed higher than 3.7 except between IPS e.max Ceram(P) and wieland coloring liquid(W) group. Conclusion: Within the limitations of this study, various coloring liquids influenced the L*, a*, and b* values of colored zirconia. IPS e.max Ceram(P) and wieland coloring liquid(W) group did not show clinically perceiving color difference.

Purpose: This report intend to provide basic materials of Musculoskeletal diseases prevention program development and preventive measures establishing by surveying Musculoskeletal symptoms. Musculoskeletal disease and Musculoskeletal disease prevention act about dental technician in Daegu. Methods: From October. 2012 to November. 2012 by conducting self - survey using questionnaire and use unit490 final analysis data. Results: In dental Technicians, as the musculoskeletal symptoms back or waist pain rate appear such as 28.2% and as the musculoskeletal disorders, the shoulder region pain complaint rate appear highly such as 87.4%. Musculoskeletal disease prevention act was highly appeared man more than women, the married than the unmarried, over 10 years dental experience, fewer working hours per day, the average monthly income is greater regular medical check-up dental technician than technician who do not. As working environment, In case working in laboratory whch dust is well ventilated and with a barrier, Musculoskeletal disease prevention act rate was highly appeared more than another technician who do not. Conclusion: We must prepare an effective preventive measures. To development Musculoskeletal disease prevention program suitable for dental technic working and make obliged to practice.

Purpose: The purpose of this study is to analyze denture satisfaction by burdened cost types. Methods: All 588 subjects in Gyeongsangnam-do, Korea was surveyed randomly. The study was conducted for about 24 days from March 28th to April 20th, 2014. The objects who participated in the survey were offered selfreport questionnaires for this study. Results: Satisfaction with Half Price of the National Health Insurance Support Denture patients appears the highest point of 2.98 0.22, and The Governor Pledge Free Denture appears 2.90 0.17 the lowest. Also Pay Denture appears 2.96 0.21. Provincial authority regulated medical carelessness inefficiently and at all during the procedure, without having to pay the cost of individual. also provincial authority support low budget. This is the result from the lowest satisfaction of The Governor Pledge Free Denture patient. Conclusion: According to the survey results, The Governor Pledge Free Denture and The Total Pay Denture's satisfaction are higher than The National Health Insurance Support Denture. and The National Health Insurance Support Denture are more uncomfortable than pay denture to use.

Purpose: This study intends to set standard for organizing the curriculum of short-term dental technicians and the change of job environment, as well as the knowledge & training, by identifying the importance and actual job performance of dental technicians following job analysis in the university education of Dept. of Dental Laboratory Technology, and furthermore to foster junior executives to cope with modernization and globalization. Methods: The tools used in this study are based on the job analysis of research report suggested by National Health Personnel Licensing Examination Board(Lee Gyu-seon, 2011), and it consists of general characteristic 7 items. Every competence duty was measured through Likert 5 point gauging, and internal consistency through Cronbach’s Alpha. The competence importance of entire questionnaire was .984 and its performance was .874, reflecting considerably high level, and in terms of each competence duty, high credibility was proved and high internal consistency was verified with competence importance ranging from the minimum .655 to the maximum .966 and its performance ranging from the minimum .677 to the maximum .993. Results: Competence importance and its performance in each duty on the job analysis of dental technicians were measured. In competence importance in each duty, the highest was “checking design order form”(average, 4.52), followed by “selling dental prosthesis°”(average 4.49), “making removable orthodontic appliance”(average, 4.48), “open managing dental laboratory”(average, 4.46) in order. However, “making complete denture” was found the lowest(average, 4.23), with importance of all competence dutys was considerably high level. In the performance of its competence duty, “checking design order form”(average, 4.04) was found to be the most importance competence, followed by “making conservative restoration”(average, 4.00), “making porcelain” (average 3.98), “checking working cast”(average, 3.90) in order. However it was found out that “making fixed orthodontic appliance”(average, 3.12) was the lowest, and the importance of all competence dutys was quite high level. Conclusion: The duties of dental technicians consist of 13 kinds, in total, and it was found out that “checking design order form”(average, 4.52) was the most important in the competence importance and job performance. In particular, it was revealed that there was a great difference between the competence importance and its performance in the order of “selling dental prosthesis”, “open managing dental laboratory”, “making removable orthodontic appliance”, “making CAD/CAM prosthesis”, and then “making fixed orthodontic appliance”.