• 구강회복응용과학지
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• 제24권2호
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• pp.193-201
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• 2008

하악 완전 무치악 환자의 보철수복에 있어 임플란트 식립 후 피개의치의 제작은 첫 번째 치료 옵션으로 고려되어질 수 있다. 임플란트 지지 텔레스코프 피개의치를 제작하는 경우 인공치 및 유지 장치의 배열을 위한 악간 공간이 필요하다. 임플란트 상부 보철물의 passive한 fit은 보철물의 기계적 실패를 막는 중요한 요소이다. Gold electroforming system을 이용하여 제작한 telescopic attachment는 우수한 마진 적합도 및 passive한 fit을 보이며 얇은 코핑 두께로 인하여 좁은 악간 공간에서도 사용이 가능한 장점이 있다. 본 증례에서는 4개의 임플란트 식립 후 Gold electroforming system을 이용하여 telescopic overdenture를 제작하여 기능 및 심미적으로 좋은 결과를 나타내었다.

• 대한치과보철학회지
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• 제38권4호
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• pp.402-411
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• 2000

The dental profession is currently experiencing a technology explosion. Processes are being replaced by modern, inexpensive, and precise techniques that can be used to solve complex restorative problems. Electrical discharge machining(EDM, known as spark erosion in Europe) is a nonconventional, industrial technique that has application in dentistry. EDM may be defined as a metal removal process using a series of sparks to erode material from a workpiece in a liquid medium under carefully controlled conditions. EDM is recently adopted in the dental laboratory to fabricate precision attachments, hybrid tele-scope crowns, Ti-ceramic crowns. EDM has also been used to achieve a passive precision metal-to-metal fit between the substructure bar and the removable superstructure and to correct the fit of implant retained restorations. In this article, a brief history and explanation of EDM is discussed and a description of the use of this process for fabricating attachments and crowns or for correcting the fit of cast restorations is presented.

• The Journal of Advanced Prosthodontics
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• 제12권3호
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• pp.167-172
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• 2020

PURPOSE. The aim of the present study was to investigate the passive fit of metal substructure after repetitive firing processes in implant-supposed prosthesis. MATERIALS AND METHODS. Five implants (4 mm diameter and 10 mm length) were placed into the resin-based mandibular model and 1-piece of screw-retained metal substructure was produced with the direct metal laser sintering (DMSL) method using Co-Cr compound (n = 10). The distance between the marked points on the multiunit supports and the marginal end of the substructure was measured using a scanning electron microscope (SEM) at each stage (metal, opaque, dentin, and glaze). 15 measurements were taken from each prosthesis, and 150 measurements from 10 samples were obtained. In total, 600 measurements were carried out at 4 stages. One-way ANOVA test was used for statistical evaluation of the data. RESULTS. When the obtained marginal range values were examined, differences between groups were found to be statistically significant (P<.001). The lowest values were found in the metal stage (172.4 ± 76.5 ㎛) and the highest values (238.03 ± 118.92 ㎛) were determined after glaze application. When the interval values for groups are compared with pairs, the differences between metal with dentin, metal with glaze, opaque with dentin, opaque with glaze, and dentin with glaze were found to be significant (P<.05), whereas the difference between opaque with metal was found to be insignificant (P=.992). CONCLUSION. Passive fit of 1-piece designed implant-retained fixed prosthesis that is supported by multiple implants is negatively affected by repetitive firing processes.

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2000년도 추계학술대회
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• pp.27-28
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• 2000

• 한국운동역학회지
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• 제21권1호
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• pp.25-29
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• 2011

The purpose of this study was to analyze quantitative and qualitative differences according to shoe type for the grand jete landing in ballet. The subjects for this study were 9 female ballet majors with an average of 12 years of experience. Subjects jumped, performing a front split, and landed on 1 foot, a movement called the grand jete. Analysis was performed on the students' landing. Independent variables were 3 shoe types: split sole, traditional out sole, and 5-toed forefoot shoes, with bare feet as a control group. Dependent variables were vertical passive ground reaction force and qualitative elements. Passive ground reaction force variables(maximum passive peak value, number of passive peaks, passive force-time integral, and center of pressure) were measured by the Kistler 9281B Force Platform. Qualitative elements were comfort, cushioning, pain, and fit. Statistical analysis included both 1-way ANOVA and Tukey's test for follow-up. Finalized data demonstrated that the 5-toed forefoot shoe allows the forefoot to expand and the toes to individually press down upon landing, increasing foot contact with the surface. Five-toed forefoot shoes minimize passive peaks and pain, while increasing comfort, cushioning, and fit. Most ballet movements are composed of jumping, balancing, landing, and spinning. Wearing 5-toed forefoot shoes allows for a natural range of movement in each toe, to improve both technique and balance. Pain and injuries from ballet can be minimized by wearing the correct shoe type. According to this analysis, it is possible to customized ballet shoes to increase the efficiency of techniques and movements.

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2000년도 춘계학술대회
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• pp.43-43
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• 2000

• 대한치과보철학회:학술대회논문집
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• 대한치과보철학회 2004년도 추계학술대회
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• pp.65-65
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• 2004

• 구강회복응용과학지
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• 제17권4호
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• pp.307-314
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• 2001

To evaluate the effect of misfit in two implant-supported fixed partial dentures in the posterior of the mandible, variations of the standard finite element models were made by changing the location of the gap as follows: 1) no gap present; 2) located between the gold cylinder and the abutment on the distal implant; 3) gap located between the gold cylinder and the abutment on the mesial implant. The results of this study were as follows: 1. When the location of the gap was close to the load applied on the prosthesis, the stress in the prosthesis, implant components and surrounding bone increased. 2. The presence of cantilever increased the stress in the prosthesis, implant and surrounding bone significantly, regardless of the presence of the gap. 3. When there was a gap between the prosthesis and abutment, the stress in the bone around the implant increased. 4. When passive fit was achieved, the stress was distributed widely in each component with less peak stress in each component. 5. The inner structures of the implant components, the gold screw and the abutment screw bear more stress when the prosthesis did not exhibit passive fit with the abutments than when passive fit was present.

• ETRI Journal
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• 제31권3호
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• pp.348-350
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• 2009

To fit the limited volume and power consumption of the passive radio frequency transmission system of the electronic time fuze, an improved coded mark inversion (CMI) is proposed in this letter. From the performance analysis, the energy transmission efficiency of this encoding method is at least 50% higher than that of CMI and NRZ. Finally, the experiment results show that by adopting this improved CMI, the change of DC voltage through magnetic coupling is lower than 0.2 V when the accuracy of data transmission is above 99.5%.

• 한국안전학회지
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• 제19권1호
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• pp.102-107
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• 2004

Performance based design is a recent evolutionary step in the process of designing fire protection systems. In essence, it is a logical design process resulting in a solution that achieves a specified performance. Sometimes the prescriptive solutions presented in various codes and standards are too expensive or inflexible. Often the solutions do not and enables optimization of a solution for cost and function. In this study, performance based design was carried out to determine the extent of passive fire protection for oil terminal facilities. The results of performance based design were compared with those of prescriptive code based design. Performance based design is not always more economic than prescriptive code based design but provides more reliable and effective design that is fit for the purpose.