• 대한심미치과학회지
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• 제23권2호
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• pp.77-79
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• 2014

There are several factors affected fractures of full contour zirconia (FCZ) dental prosthesis in laboratory process. First, residual moisture can cause zirconia cracks. Complete dry is requisite before zirconia sintering to prevent zirconia cracks. Second, slow cooling rate is essential to prevent cracks during zirconia sintering process. Cracks in bridge pontic area, thick dental implant prosthesis can be prevented by slow cooling rate such as 3 degree Celsius per minute during zirconia sintering. Third, slow heating rate and slow cooling rate during staining and glazing procedure is necessary to inhibit thermal shock of sintered dental zirconia. Lower preheat temperature of porcelain furnace is recommended. Finally, using diamond disc to open embrasure can lead cracks.

• 대한치과기공학회지
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• 제12권1호
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• pp.67-72
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• 1990

The purpose of this study was to find job maturity of dental technology students in Taegu area. In order to accomplish the objectives stated above, the following research methods were utilized : 1. The related literatures including previous studies and journal were reviewed to develop the questionnaire for this purpose. 2. Field survey and questionnaire survey were conducted to collect data from 360 students sampled and analyzed by frequency percentage $X^2$-score. In consquence of analysis of the responses, the finding were as follows : 1. The job maturity of students was shown high. The grade point of 98.6 percent students as a whole was above three point. 2. As compared by academic year of sophomore students was higher than that of freshmen's, and male students were shown greater score than female students.

• 대한치과기공학회지
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• 제41권1호
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• pp.31-41
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• 2019

Purpose: This provides basic data for improving educational effectiveness by selecting and applying basic vocational competency applicable to dental technology's sub-major curricula by determining and researching dental technicians' awareness levels concerning the basic vocational competency's importance. Methods: 170 dental technicians working in Daegu, Korea were surveyed using a self-administered questionnaire between 9 January 2018 and 23 February 2018. Results: 1. The highest level of the basic vocational competency elements by the awareness levels of importance in dental technology laboratories was shown in the occupational ethics, followed by technological skills, interpersonal skills, self-development levels, problem-solving skills, information skills, resource management skills and skills for understanding groups, communication skills, and mathematical skills. 2. Female dental technicians put relatively higher importance on writing documents and managing time, while males stressing on basic statistics. 3. Dental laboratory CEOs and managers put high values on resource management skills, while head technicians valuing information skills more. 4. The awareness levels concerning the basic vocational competency importance in some dental technology fields did not match those of the dental technology laboratories in the fields of porcelain, crown and bridge, and orthodontics. Conclusion : This study demonstrates that the awareness levels concerning basic vocational competency's importance in some fields of dental technology differ from those of dental technology laboratories. Developing a basic vocational competency curriculum, it seems necessary to find ways to increase educational effectiveness by selecting and applying the basic vocational competency for the respective fields of dental technology.

• 대한치과기공학회지
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• 제14권1호
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• pp.15-21
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• 1992

• 대한치과기공학회지
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• 제2권1호
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• pp.61-62
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• 1980

• 대한치과기공학회지
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• 제41권2호
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• pp.93-100
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• 2019

Purpose: This study is making a dog dental prosthesis using digital dental technology. The mechanical strength of the prosthetic material was observed in terms of compressive strength and fracture pattern. Methods: The experiment was performed using dog mandibular molars. The teeth were scanned and modeled. The specimens were made of zirconia, PMMA and Ni-Cr. The specimens were subjected to a vertical compression test with an artificial cancellous bone in UTM tester. Vertical compressive strength and fracture behavior of specimen were observed. Results: The result of observing the compressive load between specimen and artificial bone were $184.8{\pm}5.7N$ in the zirconia specimen, $185.6{\pm}8.9N$ in the PMMA specimen, and $184.4{\pm}4.0N$ in the Ni-Cr alloy specimen. Compression marks of artificial bones were observed. The fracture strength of specimen was observed. The fracture strength of the zirconia specimen was an average of 1,381.4N. The fracture strength of the PMMA specimen was an average of 572.2N. Conclusion: The crown made of three kinds(zirconia, PMMA, Ni-Cr alloy) of materials has the strength to chew about the artificial bone. zirconia and PMMA have vertical compressive strength applicable to medium dog dental prosthetic materials.

• 치위생과학회지
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• 제8권2호
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• pp.51-56
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• 2008

이 연구의 목적은 치과의료 소비자가 원하는 서비스의 중요도를 정확히 파악한 후, 치과의료서비스의 개선을 위한 자료를 얻는데 있다. 본 연구는 2008년 3월 17일부터 3월 25일까지 수원시 소재 대학의 치기공과에 재학 중인 1,2,3학년 학생 261명을 대상으로 각각 3부씩의 설문지를 배부하고, 학생 본인을 포함하여 가족과 지인에게 설문하는 방법으로 조사하였으며, 배부된 783부의 설문지 중 584부를 회수하여 분석한 결과 다음과 같은 결론을 얻었다. 치과의료기관을 선택할 때 고려하는 의료서비스와 관련된 변수들의 피어슨 상관관계를 산출한 결과 모든 영역별로 정의 상관관계가 있는 것으로 나타났으며, 각 세부영역 중 병원의 물리적 환경과 치과의사의 외향적 자질과의 상관관계가 가장 높게 나타났으며, 그 다음으로 교통의 편의성과 병원의 기본요소, 병원의 물리적 환경과 병원의 기본요소, 치과의사의 외향적 자질과 병원의 기본요소, 교통편의성과 병원의 물리적 환경, 교통편의성과 치과의사의 외향적 자질 순으로 유의한 정의 상관관계를 나타냈다. 전체 변수들 간의 고려사항 역시 정의 상관관계가 있으며, 병원의 물리적 환경을 가장 중요하게 생각하고, 병원의 기본요소, 교통 편의성, 치과의사의 외향적 자질 순으로 중요하게 생각하는 것으로 나타났다.

• 대한치과기공학회지
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• 제43권3호
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• pp.71-76
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• 2021

Purpose: In this study, thermal properties were observed by measuring the extent of thermal expansion and the amount of thermal residue that appears upon burnout on a workpiece made by using a dental digital light processing (DLP) three-dimensional (3D) printer. Methods: Thermal properties of workpieces manufactured by using two 3D printers were observed. The specimens were designed in cylindrical form with dimensions 10 mm in diameter and 10 mm in height. The control specimen was made of wax, and the experimental specimen was made of resin. The thermal expansion rate was measured by applying heat to three types of specimens, and burnout residue was measured. Results: The thermal expansion rate of the wax pattern (WP) specimen was 0.93%±0.05%, of the RP1 specimen was 1.30%±0.08%, and of the RP2 specimen was 1.20%±0.09%. Measuring the recovered residue yielded residual amounts of 0.2% for the WP specimen, 1.1% for the RP2 specimen, and 1.8% for the RP1 specimen. Conclusion: 1. From measurements of the workpieces manufactured by dental DLP 3D printing, the thermal expansion rate was found to be higher than that of wax. 2. As a result of measuring burnout residues on the workpieces manufactured by dental DLP 3D printing, the required summoning temperature to obtain suitable castings was determined to >750℃.

• 대한치과기공학회지
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• 제43권4호
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• pp.145-152
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• 2021

Purpose: This study aimed to produce resin prosthetics using a dental barrel finishing machine. For dental resin grinding, the ingredients of the barrel finishing media were analyzed, and surface residues of the resin were observed. Methods: Two types of barrel finishing media for dental resin grinding were tested. Specimens were made from thermal polymerized, auto polymerized, and photopolymerized resins. Finishing media were analyzed through energy-dispersive X-ray spectroscopy (EDS) component analysis and inductively coupled plasma-optical emission spectrometry (ICP-OES) component analysis. Then, the prepared specimen was barrel finished for 25 minutes using two types of barrel finishing media, and scanning electron microscope was photographed to observe the surface residues. Results: As a result of EDS component analysis, both types of finishing media were analyzed for the components of C, O, Zr and Al elements, and industry media (IM) was further analyzed for the components of Si and Mg elements. In the ICP-OES component analysis, Cd and As, which are harmful elements, were detected in IM, and no harmful elements were detected in manufacturing media (MM). Because of observation of surface residues, no residues were observed in the three types of resin specimens that were barrel finished with two types of finishing media. Conclusion: Surface residue wasn't observed on the specimens polished using two types of finishing media. However, in IM, Cd and As, which are harmful elements, were detected, making it inappropriate for clinical use. In MM, harmful elements were not detected; therefore, clinical use will be possible.

• 대한치과의료관리학회지
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• 제11권1호
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• pp.28-37
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• 2023

In this study, in order to analyze the effects of dental technology students' degree of satisfaction with their major and sense of self-esteem on college life stress, we conducted a self-administered questionnaire for 270 dental technology students. conducted a frequency analysis, t-test, one-way ANOVA, correlation analysis, and multiple regression analysis, and the results are as follows. As a result of analyzing the degree of major satisfaction, there was a significant difference in the department satisfaction (p<.05). The average score in major satisfaction was relatively high at 3.68. As a result of analyzing the level of self-esteem, there was a significant difference in grade and department satisfaction (p<.05). The average score in self-esteem question was relatively high at 3.75. As a result of analyzing the level of college life stress, there was a significant difference in the department satisfaction (p<.05). The average score for each college life stress area was relatively low at 1.97. As a result of analyzing the correlation between college life stress, major satisfaction, and self-esteem, college life stress was found to have a significant negative (-) correlation with major satisfaction and self-esteem. As a result of a regression analysis conducted on the effect of self-esteem and major satisfaction on college life stress, the variable that most influenced college life stress was found to be the self-esteem factor.