• 대한치과기공학회지
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• 제24권1호
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• pp.95-104
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• 2002

For biomedical applications, Ti-X%Zr-Y%Nb-0.2%Pd(X:10$\sim$20, Y:2$\sim$8) alloys not containing harmful Al and V were newly designed, and the effect of alloy composition and heat treatment on the microstructure and mechanical properties was investigated. From the results, it was shown that the mechanical properties were enhanced with the addition of Zr or Nb. The effect of heat treating on room temperature strength was investigated by aging treatment after solution treatment. The mechanical properties of Ti-20%Zr-4%Nb-0.2%Pd alloy aged at 400$^{\circ}C$ for 10hrs was found to be superior to those of the pure Ti and Ti-6%Al-4%V ELI alloy.

• 대한치과기공학회지
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• 제8권1호
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• pp.45-50
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• 1986

This study investigated the effect of burnout temperature on the castability of some nickelchromium alloys for porcelain fused to metal system and the effect of beryllium on the castability. Four alloys were evaluated: two contained beryllium(rexillium III, Super I) and two nonberyllium(Unibond, NNB). five burnout temperature, ranging form 100$^{\circ}F$ to 1800$^{\circ}F$, were aet at 200$^{\circ}F$ intervals for this study. The results obtained were as follows: 1. Beryllium-containing alloys were more castable than nonberyllium-containing alloys. 2. There was an optimal burnout temperature of range from 1400$^{\circ}F$ to 1600$^{\circ}F$ for the berylliumcontaining alloys studied. 3. An optimal burnout temperature for the nonberyllium alloys was not established.

• 대한치과기공학회지
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• 제21권1호
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• pp.97-114
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• 1999

The first function of occlusion is mastication. Therefore the functional restoration of occlusal surface is very important. The restoration of occlusal surface is three method as wax bite technique, F.G.P. technique, cone technique. Many dental technician is using compound method. I have knew common point on each teeth during I have waxing up wax pattern. So I studied on the design waxup technique for maxillary molar occlusion. The results of the study were as follows ; 1. The dam wax up method can restore axial contour of teeth very easy and make short working time of wax pattern. 2. The height of dam must be same with cusp of adjacent teeth. 3. Automatically the contour of tooth is appeared if the contour of dam is relationship with cuspid line of adjacent teeth. 4. The height of contour of buccal, lingual surface is formed natural curve to add fluid wax by gravitation. 5. The development groove of Maxillary premolar is appeared V form. 6. The development groove of Maxillary molar is appeared W form. 7. The embrasure is formed to carve around contact point area as round convex. It affects to axial form of tooth. 8. I was knew that the lingual groove and stuart's groove of molar runs parallel with oblique ridge. 9. The buccal groove of molar is formed parallel with direction of teeth arrangement.

• 대한치과기공학회지
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• 제18권1호
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• pp.5-13
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• 1996

Among investment for dental casting, we selected 4 kinds of investment(2 Gypsum-bonded and 2 Phosphate-bonded) and prepard 120 specimen by dividing into two cast of using Ring and Ringless case from $0^{\circ}C$ to $30^{\circ}C$ at interval of $10^{\circ}C$ to invest in fluence on the fitness of casting body according to the liquid temperature of Gypsum-bonded and Phosphate-bonded investment. The result was as follows; 1. Gypsum-bonded investment showed best fitness at $30^{\circ}C$ representing difference of singnificance in order of $20^{\circ}C$, $10^{\circ}C$, and $0^{\circ}C$, From the difference of investment, Deguvest was proved superior than Cristobalite. 2. Phosphate-bonded investment showed no severe difference at $10^{\circ}C$ and $20^{\circ}C$, but showed better fitness at $10^{\circ}C$, representing difference of significance in order of $0^{\circ}C$, $30^{\circ}C$, difference of significance was shown between investment also. 3. In Ringless investing method, there were no difference of significance in Deguvest CF and Unovest. 4. When using a Ring with a Sheet of asbestos liner installed, there was some difference of significance representing superiority of Ringless investing method.

• 대한치과기공학회지
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• 제5권1호
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• pp.31-34
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• 1983

1) 종래의 activator 보다 간결한 장치. 2) 상.하악체를 고정한 불편을 덜고 심미적인 면에서 우수하였다. 3) 저작기능을 회복하여 하시에도 장착이 가능하였다. 4) 짧은 시간에 소기의 효과를 얻을 수 있었음. 장착 2주부터 교합관계 Reduction 및 순측 pushed wire bow로 수정하였고 6주부터 현저한 변화를 얻었다. 5) 복잡한 appliance가 요구되지 않았으며 비용 역시 경감되고 수번의 수정이 요구되지 않았음.

• 대한치과기공학회지
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• 제20권1호
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• pp.139-143
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• 1998

This study was carried out to collect basic dates on fluoride intake from drinking water, and the apperance of mottled teeth after taking samples form 5 selected waterways from Iksan region's reservoir to the filtration plant for examination of the fluoride content. The results are as follows. 1. It indicatied that from Hoojung reservoir $2.17{\pm}0.95ppm$, Bulsan reservoir $1.93{\pm}0.23ppm$ and Yoolso reservoir $2.19{\pm}0.10ppm$. 2. Significances were found between Shinhung reservoir $2.57{\pm}1.22ppm$ and Uhwoo reservoir $0.80{\pm}0.55ppm$. 3. Except for the Uhwoo reservoir, the remaining 4 reservoir exceeded the standard fluoride content of 0.50-1.00ppm. For the residents in the region where they use natural water with fluoride content exceeding the standard 1.00ppm as their drinking water and the apperance of mottled teeth should be carried out.

• 대한치과기공학회지
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• 제12권1호
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• pp.121-124
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• 1990

The purpose of this study was to evaluate the effect of three different retention forms on the bond strength when complete denture repaired. Total 75 samples were divided into 3 groups(Dove-tail form, bevel form, rabbit form). The completed resin samples were compressed in Instron Testing Machine until gross fracture occurred to examine the effect on the bond strength of resin base. The results of the experiment were as follows : 1. The difference of bond strength according to three retention forms were not statistically significant(P>0.05). 2. Dove-tail form was strongest to bond strength among the three retention forms.

• 대한통합의학회지
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• 제3권3호
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• pp.43-47
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• 2015

Purpose : The aim of this study was to report a follow-up study on the prognosis following the arthrocentsis for the painful temporomandibular dysfunction not responsible to the conservative splint therapies. Arthrocentsis of TMJ is a simple precedure that can be performed in the out-patient clinic under the local anesthesia without any reported complications. Method : Seventy patients had been followed after the arthrocentsis for over 6 months. Maximum mouth opening, TMJ pain, TMJ noise, and their changes by time were examined and compared statistically. The effectiveness of the treatment was evaluated in terms of the postoperative range of maximal mouth opening (MMO) and the degree of postoperative pain score. Predictors which was analyzed were age, duration of painful locking, MMO, the degree of pain, preoperative clicking and the amounts of irrigation fluid. Result : The result of this study were as follow; 1) Mouth opening was improved from 32.6 mm to 42.4 mm in the maximum inter-incisal distance. 2) TMJ pain was decreased in 45.7%. 3) TMJ clicking and noise disappeared in 60.0%, but recurred in 40.0%. Conclusion : Amounts of irrigated solution recovered to normal MMO and the appeareance of perioperative clkicking may be predictors of the successful results of arthrocenetesis of ADD without reduction of TMJ.

• 대한치과기공학회지
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• 제23권2호
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• pp.17-47
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• 2002

The purpose of this study was to examine the 2001 curricula in 17 departments of dental technology across the nation in an attempt to find out the educational realities of the departments by term and school year and serve as a basis for the development of more advanced, efficient dental technology curriculum and common educational objectives. For that purpose, the 2001 curricula of the three-year dental laboratory technology departments were analyzed by school year and term to calculate the amount of required credit, the number of subjects, and the weekly classes for electives and major. The findings of this study could be listed as below: 1. The departments of dental laboratory technology nationwide investigated require students to get 120 to 135 credits in total. Out of the credits, 10 to 25 credits are assigned to the electives, and 106 to 11 8 credits are given to the major. 2. There are 50 to 68 subjects in the departments of dental technology. 5 to 16 subjects are the electives, and 41 to 59 are the major. 3. There are 150 to 196 classes per week, which consist of 10 to 30 ones for the electives and 137 to In for the major. 4. The curricula for the first semester of the first year are as follows: 1) 20 to 24 credits are required. 4 to 11 credits are alloted to the electives, and 9 to 19 credits are assigned to the major. 2) The number of subject is 9 to 13, which are composed of 2 to 7 for the electives and 4 to 9 for the major. 3) The weekly classes are 22 to 29. The classes for the electives range from 4 to 14 per week, and 10 to 20 classes a week are for the major. 5. The curricula for the second semester of the first year are as below: 1) There are 20 to 25 credits. 3 to 12 credits are assigned to the electives, and 12 to 19 credits are for the major. 2) The number of subject is 10 to 14, which consist of 2 to 6 for the electives and 6 to 10 for the major. 3) The weekly classes are 22 to 29. and 3 to 12 classes a week are for the electives, and 15 to 24 classes are for the major. 6. The curricula for the first semester of the second year are as below: 1) The number of credits ranges from 20 to 24. Only six colleges offer 2 credits for the electives and the major account for 18 to 24 ones. 2) There are 8 to 12 subjects. Only six colleges offer one or two electives, and 8 to 12 are the major. 3) The weekly classes are 23 to 33. Only six colleges offer 2 or 3 classes a week for the electives, and 21 to 33 classes are for the major. 7. The curricula for the second semester of the second year are as below: 1) The number of credits ranges from 19 to 24. Only two colleges offer 2 credits for the electives and the major account for 18 to 24 ones. 2) There are 7 to 12 subjects. Only two colleges offer one or two electives, and 8 to 12 are the major. 3) The weekly classes are 24 to 36. Only two colleges offer 2 classes a week for the electives, and 24 to 36 classes are for the major. 8. The curricula for the first semester Of the third year are as below: 1) There are 16 to 24 credits. Just a college assigns 2 credits to the electives, and 16 to 24 credits are given to the major. 2) The number of subject is 5 to 12. Only a college offers one elective for optional course, and 5 to 12 are the major. 3) The weekly classes range from 18 to 39. Just a college offer 2 classes a week for the electives, and 18 to 39 classes are for the major. 9. The curricula for the second semester of the third year are as below: 1) There are 16 to 23 credits. Just a college assigns 2 credits to the electives, and 16 to 23 credits are given to the major. 2) The number of subject is 5 to 12. Only a college offers one elective for optional course, and 5 to 12 are the major. 3) The weekly classes range from 18 to 39. Just a college offer 2 classes a week for the electives, and 18 to 39 classes are for the major.

• 대한치과기공학회지
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• 제10권1호
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• pp.177-183
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• 1988

This paper aims to examine ceramic shade prescriptions for work authorizations in all its aspectclincal information, recording information, technical considerations, extended application, practical applications. The results are as follows : 1. The basic application provides essential data for ceramic veneer fabrication. 2.Three-dimensional information divides the space for body and enamel components. 3. The second body shade selection improves shade matching in the middle one-third of the tooth and enhences the appearance of the enamel component. 4. Ceramists are encouraged to recognize the influence each component has upon the total shade composition. 5. A format is established for recording clinical information. 6. The use of available ceramic systems is seemingly unlimited. The method presented provides flexisility for recording the most detailed shade information in simple graphic and verbal terms. 7. Technical simplification is a by-product of complete, precise work information.