Earticle

Purpose: The purpose of this study was establishing process of manufacturing dental prosthesis by using eZIS system(DDS Inc.,Korea). Methods: To evaluate accuracy verification, the test was practiced two ways. First, Comparison of 3D printing models and stone models was practiced by using 3D superimposing software. #36 prepared master model was scanned by eZIS system and three ‘Veltz3D’ 3D printing models and three ‘Bio3D’ 3D printing models were manufactured. three stone models were manufactured by conventional impression technique. Second, Fitness test was practiced. the 3D printing models and the stone models was compared by manufacturing same resin crown. #36 prepared master model was scanned 9 times and manufactured (milled) 9 resin crowns by eZIS system. These crowns were cemented three ‘Veltz3D’ 3D printing models, three ‘Bio3D’ 3D printing models and three stone models. These crowns were sliced mesiodistal axis and gaps were measured by digital microscope. Results: The average accuracy of Bio3D models were 65.75%. Veltz3D(Hebsiba) models were 60.11% Stone models were 41.00%. Conclusion : This study results showed 3D printing model is similar with stone model. So it was under clinical allow, didn’t affect final dental prothesis. There were no significant differences in the appearance of the three types of milling crowns.

Purpose: Automatic dental prosthesis manufacturing process was accelerated by the spread of dental CAD / CAM system. The CAD / CAM system with milling alloys were needed supplement. So, sintered alloy blocks were introduced. In this study, we want to study sintered alloy block. And to evaluate the alloy block manufacture and alloy properties. Methods: The alloy powders were prepared by high pressure water dispersion method. The sintered alloy blocks were prepared by low temperature pressing method. Their components observation were EDX, and the alloy structure was observed by XRD. Results: Co-Cr alloy powders were observed to have a circle shape with an average diameter of about 100㎛ and a Ni-Cr alloy powder had a circle shape with an average diameter of about 50㎛. The Co-Cr alloy block is composed of Co (34.62 wt%), Cr (17.33 wt%), Mo (2.98 wt%), Si (0.36 wt%) and C (44.17 wt%). The Ni-Cr alloy powder was composed of Ni (40.29 wt%), Cr (19.37 wt%), Mo (3.53 wt%), Si (0.52 wt%) and C (33.18 wt%). The peak of the Co and CoCr peaks were observed in the CoCr alloy body by the means of XRD study. Cr2Ni3 of the peak was observed in the Ni-Cr alloy material. Conclusion : As a result, the following conclusions were obtained. 1. Prepared by high-pressure water-law Co-Cr alloy powder has an average diameter 100㎛, Ni-Cr alloy powder was found to have the form of sphere having an average diameter 50㎛. 2. Co-Cr alloy and Ni-Cr alloy block produced by low-temperature processing showed a certain ratio. 3. In the XRD study, Co phase appeared in Co-Cr alloy block after sintering. and Cr2Ni3 phase appeared in Ni-Cr alloy block after sintering.

Purpose: In this study, we aim to provide primary source of data for developing a learning program that enhances the students’ learning by critically analyzing and adopting the effective class participation factors of the students. Methods: A questionnaire survey has been conducted from the beginning of May to the end of October, 2017. Subjects of the survey was the dental technology students living in W-city et al by random sampling method along with written informed consent. Out of 630 distributed questionnaires, 584 results were used for our analysis. Results: Firstly, the average score of the class participation of all the subjects was 3.08 points out of 5.0, which was broken down into class activity (3.53 points), passion about class (3.51 points), communication factors (2.88 points), class preparation (2.77 points), class extension (2.76 points). Secondly, statistically significant correlations were found between class participation and class satisfaction as shown in (p<.01). Class participation factors that affect the class satisfaction were class preparation(p<.001), class activities(p<.001), passion about class(p<.001), which reveals positive and meaningful results. Explanatory power of the model turned out 50.3%. Conclusion : Considering that class preparation, class activities, and passion about class played a key role in class satisfaction of the student, teachers need to be open minded to reflect the learners’ personalized demands and needs in preparing and managing their class. Additionally should be in tandem that provides the students with various routes of class participation.

Purpose: The main purpose of this study is to develop assessment measures for the quality of service for dental labs. Methods: In order to construct the measure of service quality assessment for dental labs, relevant modifications were extracted around theoretical studies, and the survey was conducted on dental technician workers through internet survey. final scale questions were extracted through exploratory factor analysis and confirmed factor analysis of measurement variables, the demographic characteristics of the subjects and the perceptual difference of dental labs were analyzed for the extracted variables. Results: The final five variants of the interactive factor analysis that include the ability to change employee growth, reliability, responsiveness, materiality, interoperability, confirmatory factor analysis excludes variations in employee growth wages, welfare benefits, by changing its name to network capabilities, the quality of service factors for the final dental labs consisted of five variations: network competence, reliability, responsiveness, materiality and interoperability. Conclusion : The service quality of the dental labs showed that the reliability of the product related to the dental materials and the product production responsiveness related to the production order, the Materiality of the materials and equipment of the dental labs, the Interoperability responsiveness related to dental orders, And the importance of network capability to form a mutual network.

Purpose: The research comprehends learning attitude level of Dental Technology Department students, searches variable element to affect and is trying to provide basic material of method arrangement to induce change of positive learning attitude. Methods: It was conducted survey 410 students, who understand purpose of the research, consentient to involve research, in universities which is located in Daegu area, Daejeon City, Gangwon province from Aug., 1stto Nov.,10th2017, Questionnaires were distributed to 410 students totally. it was finally analyzed 374 questionnaires except 36 questionnaires that answer was not sufficient. Results: The positive answer over ‘Average (3)’ among study attitude factors was presented highly in order of ‘Targeting & Execution’ (3.351). ‘Effective Content Summary’ (3.307), ‘Study Plan’ (3.173), ‘Priority and Self-Management’ (3.116), and ‘Study Habit & Enhancement’ (2.925) showed negative trend under average. The five sub-factors of learning attitude were examined according to general characteristics and there were statistically significant differences according to gender, grade, high school of origin, academic aptitude(p<0.01, p<0.001). Conclusion : As male students show more positive learning attitude than female students, we need to develop more special programs to encourage them. Meanwhile we also need to find out a motive to bring positive effect to change the academic aptitude and learning attitude of female students, or methods to improve their learning attitude in a complementary way by their high school, gender and grade.

Purpose: The purpose of this study was to verify the remake rate and cause of dental prosthesis and to investigate major factors of remake of dental prosthesis. Methods: This study carried out self-administered questionnaire survey from 126 nationwide dental laboratory CEO and directors, which was conducted from September to October in 2016. Results: Total remake rate of dental prosthesis was 10.1% at the nationwide dental laboratories. It was in order of remake rate of dental prosthesis 11.8% for CAD/CAM, 11.5% for porcelain and 11.0% for implant prosthesis. Error of clinical impression was the highest remake cause(63.7%). Nevertheless, dental laboratory take the responsibility of expense for remake of dental prosthesis, regardless of remake cause(67.4%). There was no relation between dental laboratory characteristics and the remake rate of dental prosthesis(p>.05). Conclusion : The remake rate of dental prostheses should be reduced to minimize the economic loss of dental laboratories and raise dental prosthesis satisfaction. It is required to communicate of dentist, dental technicians, and patients, moreover, undistorted information about oral environment should be provided to the dental technicians.

Purpose: The purpose of this study was to evaluated the process of model analysis, design, and production for a full mouth prosthetic rehabilitation of function, esthetics, and pronunciation. Methods: This is a case report of class III malocclusion with a severe anterior incisor occlusion and a prosthetic treatment of patient with poor occlusion of posterior teeth. A provisional restoration based on the diagnostic wax-up was applied to the patient. And then functions, esthetics, and occlusal stability were observed during 4 week tracking period. Final restorations were delivered and evaluated based on a systematic analysis, diagnosis and treatment plan. Results: We confirms that this case study obtained the satisfactory results in terms of functions and esthetics. Conclusion : If we can give the patient the continuous evaluation and progress monitoring, we expect the dentist and the dental technician to design the prosthesis successfully.