• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.1-10
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• 2008

The purpose of this study was to compare the oral health status of elderly people living in nursing home with private home in Busan, Kimhae and Jinju in Gyeongnam province for development oral healthy policy of elderly people. 253 elderly subjects aged more than 65 in a hall for the aged and special medical treatment hospital are made up questions. The date was analysed using the SPSS 13.0 program. The obtained result were as follows. 1. 39.5 percent elder people recognize that their subjective oral health is not good. In the case of above three times in brushing tooth a day, 29 percent people are less their oral health is good. As the number of times of brushing tooth decreases, the percent feeling their oral status good decrease(p<.05). 2. The respondents who have visited the dentist within one year are less than people with no visit. Also the percent having a mind that their oral health status is good is higher in the respondents having scaling than them without scaling(p<.05). The respondents who answer that their diet is not bad is most in the ratio of people feeling subjective oral health status good(p<.001). 3. The portion of people feeling their oral status not healthy is highest in the respondents without tooth(p<.05). 4. Among the respondents answering their subjective oral health is not good, the some problem of conversation due to no tooth or denture and relation with others is issued each(p<.001). This study suggests that perceived toothbrusing frequency and periodic scaling with oral health among the elderly. The finding of this study will helpful to policy makers to design plants to increase the oral health related quality of life among the elderly.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.150-156
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• 2020

The purpose of this study was to evaluate the factors affecting self - esteem of orthodontic patients. The factors affecting the self - esteem of the orthodontic patients were monthly incomes, and the factors influencing the necessity of orthodontic treatment were the highest at 20-25 years of age. The factors affecting the self - esteem of the orthodontic patients were the order of correction (β= 0.186), dental treatment satisfaction (β= 0.236), interpersonal relationship (β= 0.407), and the explanatory power of the model was 27.6%. Based on these results, it is necessary to continuously study the psychological characteristics to improve the recognition of the need for correction of orthodontic patients, the satisfaction of dental treatment, and the interpersonal relationship.

• Journal of Technologic Dentistry
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• v.26 no.1
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• pp.97-104
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• 2004

A new Ti-10Ta-10Nb alloy has designed and examined some possibility of forming more passive oxide film by oxidation treatment which is closely related to corrosion resistance and biocompatibility. Ti-6Al-4V and Ti-10Ta-10Nb alloys were prepared by consumable vacuum arc melting and homogenized at 1050$^{\circ}C$ for 24hours. Alloy specimens were oxidized at the temperature range of 400 to 750$^{\circ}C$ for 30minutes, and the oxide films on Ti alloys were analysed by optical microscope, SEM, XPS and TGA. Cytotoxicity test was performed in MTT assay treated L929 fibroblast cell culture by indirect method. It is found out that the oxide film on Ti-10Ta-10Nb alloy is denser and thinner compared to Ti-6Al-4V alloy. The weight gain during the oxidation was increased rapidly at the temperature above 650$^{\circ}C$ for Ti-6Al-4V alloy and above 700$^{\circ}C$ for Ti-10Ta-10Nb alloy respectively. It was analysed that the passive film of the Ti alloys consisted of TiO2 through X-ray photoelectron spectroscopy (XPS) analysis. It is found out by cytotoxicity test that moderate oxidation treatment lowers cell toxicity, and Ti-10Ta-10Nb alloy showed better result compared to Ti-6Al-4V alloy.

• Journal of Technologic Dentistry
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• v.40 no.3
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• pp.125-131
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• 2018

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 $100{\mu}m$ and a Ni-Cr alloy powder had a circle shape with an average diameter of about $50{\mu}m$. 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 $100{\mu}m$, Ni-Cr alloy powder was found to have the form of sphere having an average diameter $50{\mu}m$. 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.

• Journal of Technologic Dentistry
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• v.28 no.1
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• pp.103-120
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• 2006

In this study, we investigated the growth rate on the basis of the sex and the year among the subjects of the licensed dental technicians from the year 1970 to 2003 in Korea. In line with this investigation, this study aims to provide a basic material with regard to the state of dental technician workforce by sex and to suggest a need to reassignment of workforce by sex in accordance with the specific job description. The results of the study are as follows; First, among the licensed dental technicians from 1970 to 2003, males came to 11,589 and females, 5,976, which shows the number of males are 1.9 times higher than that of females. To put the mean sexual composite from 1970 to 2003, male was 82.9% and female 17.1%, indicating the number of males are 4.8 higher than that of females. Second, Of the mean increasing rate until the year 2003 in contrast to 1970, male was about 351 and female was about 181, which shows the number of males increased 1.94 times higher than the females. Comparing to the mean increasing rate of the last year, female came to 25.56% and male 10.73%, which reveals that the females were about 2.4 times higher than the males. In the case of the growth rate, females increased by 1,196,20 times and the males, 26,41. As a result the growth of females are about 45.3 times higher than the males. Third, in the case of the growth rate from 1980 to 2003, females came to 47.85 times and males 9.16, which shows the growth rate of the females was about 5.2 times higher than the males. In contrast to the year 1987, the growth rate until 2003 shows that the females came to 5,13 times and the males 2.70, which indicates the growth rate of females was about 1.9 times higher than males. Fourth, Compared to the year 1990, the growth rate until 2003 shows that females came to 3.40 times and males 2.03 indicating the growth rate of the females was about 1.7 times higher than males. In contrast to the year 2000, the growth rate till 2003 shows that females was 1,34 times and males 1.15 times increased. Fifth, the ratio of sex by the year among the licensed dental technicians is as follows; ratio of male to female in 1970 was 91.2 to 1. In 2003 the ratio came to 2.0 to 1. The number of growth by sex in 1970 came to 24.0 males to 1 female. But the figure was equalled in 2003.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.196-201
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• 2000

This study was conducted to investigate various flavor components of barley meju during fermentation. The change of PH was $5.2{\sim}5.6$. L-value and b-value gradually decreased. a-value gradually increased until fifth day and then decreased. Among 75 flavor compounds identified in barley meju, 10 aldehydes and 10 ketones were most in number followed by 9 acids, 9 phenols, 7 hydrocarbons, 7 alcohols and 6 esters. The contents of ethyl acetate $(67.8{\sim}89.1%)$ was more than those of any ether component followed by hexadecanoic acid $(1.21{\sim}12.00%)$ and tetramethylpyrazine $(0.06{\sim}12.30%$).

• The Journal of the Convergence on Culture Technology
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• v.4 no.1
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• pp.57-65
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• 2018

The purpose of this study was to investigate the factors affecting the actual condition and effectiveness of orthodontic treatment among some dental hygienists and students. This study was carried out from September to December, 2016 to describe the purpose of the study and the method of writing the questionnaire for some dental hygienists and students. The final 430 sections were analyzed and analyzed using PASW Statistics 18.0. First, the duration of orthodontic treatment was 34.4% for college students, 36.9% for orthodontic treatment for less than 2 ~ 3 years, and 62.3% for internal motivation. The factors affecting the orthodontic treatment effect were the patient's cooperativeness and the hospital's scale was the lowest. The higher the grade level, the more the clinical experience and dental part-time experience were, the higher the correlation between dental specialty and dental hygienist's medical service, education and counseling was .521(P<0.001). The higher the level of cooperation, the higher the grade level, the more dental treatment and orthodontic treatment experience, the lower the level of family co - operation. Therefore, it is important to emphasize the importance of cooperation of orthodontic patients and to develop a strategic program for each individual patient.

• Journal of Technologic Dentistry
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• v.8 no.1
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• pp.37-43
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• 1986

The purpose of this study is to evalute the effects of melting and casting procedures on the castability of some N-Cr and Ag-Pd alloys. One Ag-Pd alloy and two Ni-Cr alloys were chosen for study, and the first casting group of these alloys were used as the control, and with which the castability of the first recase group and the mixture group of the first recast and as much amount of the first casting alloy was compared. The results of this study were as follows: 1. The castability of the first recast alloys veried significantly depending upon the presence or abscence of the first casting alloy and the kind of alloys. 2. When the first recast alloy was mixed with as much amount of the first casting alloy, there was no significant difference in castabilityh between the first recast group and the first casting group. 3. When the first recast alloy was used alone, the castability veried significantly depending upon the kind of alloys, i.e., the castability of Rexillium III and Palliag M was decreased significantly when compared with that of the first casting groups, while that of C & B Alloy was not.

• Journal of Technologic Dentistry
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• v.36 no.3
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• pp.141-147
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• 2014

Purpose: Dental casting #Gr I (Co-25Cr-5Mo-3Sn-1Mn-1Si), #Gr II (Co-25Cr-5Mo-5Cu-1Mn -1Si) and #Gr III (Co-25Cr-5Mo-3Sn-5Cu-1Mn-1Si) master alloys of granule type were manufactured the same as manufacturing processes for dental casting Ni-Cr and Co-Cr-Mo based alloys of ingot type. These alloys were analyzed melting processes with heating time of high frequency induction centrifugal casting machine using infrared thermal image analyzer. Methods: These alloys were manufactured such as; alloy design, the first master alloy manufatured using vacuum arc casting machine, melting metal setting in crucible, melting in VIM, pouring in the mold of bar type, cutting the gate and runner bar and polishing. These alloys were put about 30g/charge in the ceramic crucible of high frequency induction centrifugal casting machine and heat, Infrared thermal image analyzer indicated alloys in the crucible were set and operated. Results: The melting temperatures of these alloys measuring infrared thermal image analyzer were decreased in comparison with remanium$^{(R)}$ GM 800+, vera PDI$^{TM}$, Biosil$^{(R)}$ f, WISIL$^{(R)}$ M type V, Ticonium 2000 alloys of ingot type and vera PDS$^{TM}$(Aabadent, USA), Regalloy alloys of shot type. Conclusion: Co-Cr-Mo based alloy in addition to Sn(#Gr I alloy) were decreased the melting temperature with heating time of high frequency induction centrifugal casting machine using infrared thermal image analyzer.

• Journal of Technologic Dentistry
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• v.6 no.1
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• pp.19-26
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• 1984

This Experimental study was performed to study the effect of the heat soaking and the diameter of pattern on the casting ability of three nonprecious alloys manufactured for porcelain-metal restorations, with respect to their ability to reproduce test pieces by casting over a selected range of uniform diameters. Samples of total 60 were constructed and divided into 6 groups according to the two variables, the diameter and the heat soaking. The completed cast samples were examined visually and measured with a caliper calibrated to 0.05mm. The results obtained were as follows: 1. Length cast was significantly related to the diameter to be cast, especially in the case of the marrowest diameter of 230m. 2. Length cast not significantly related to the heat soaking. 3. The completeness of casting was significantly related to the diameter to be cast, particularly in the case of the narrowest diameter of 230m. 4. The completeness of casting was not significantly related to the heat soaking. 5. All of the three nonprecious alloys used for this experiment were significantly different from an ideal alloy in the completeness of casting.