• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.3
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• pp.7-11
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• 2011

In this paper, we proposed a simple and high-yield printing process for source and drain electrodes of organic thin film transistor (OTFT). The surface energy of PVP (poly 4-vinylphenol) gate dielectric was decreased from 56 $mJ/m^2$ to 45 $mJ/m^2$ by adding fluoride of 3000ppm into it. Meanwhile the surface energy of source and drain (S/D) electrodes area on the PVP was increased to 87 $mJ/m^2$ by treating the areas, which was patterned by photolithography, with oxygen plasma, maximizing the surface energy difference from the other areas. A conductive polymer, G-PEDOT:PSS, was deposited on the S/D electrode areas by brushing painting process. With such a simple process we could obtain a high yield of above 90 % in $16{\times}16$ arrays of OTFTs. The performance of OTFTs with the fluoride-added PVP was similar to that of OTFTs with the ordinary PVP without fluoride, generating the mobility of 0.1 $cm^2/V.sec$, which was sufficient enough to drive electrophoretic display (EPD) sheet. The EPD panel employing the OTFT-backpane successfully demonstrated to display some patterns on it.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.603-613
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• 1995

The purpose of this investigation was to evaluate on the biodegradability, biocompatibility and tissue regenerative capacity of synthetic bioabsorbable membranes in beagle dogs. For animal study, 9 adult beagle dogs were used to examination, on the surgical implantation of membranes and histological analysis. In each animal, the 3rd and 4th premolars of the both sides of the mandible were selected as test teeth. Two types of bioresorbable membranes including "Guidor membrane", "S-membranes" were used to examining for biological activity, and also Gore-tex membranes was used for positive control. Surgically created defects were made in 2 premolars of both sides of the mandible at $3{\times}4mm^2$ in size and tested membranes were implanted in the defected area. A plaque control regimen was instituted with daily tooth brushing with a 0.1% chlorhexidine digluconate during experimental periods. All the experimental animals were sacrificed after 2, 4, and 8 weeks from surgery and undecalcified slides were prepared using the "sawing and grinding" technique described by Donath and Breuner". In biodegradability, all the membranes were started their biodegradation from two weeks after implantation and gradually demolished of their frame morphology from eight weeks. However, demolition of membranes in 8 weeks after implantation was highest in Guidor membranes and followed by S-membranes. Biocompatibilityof two kinds of biodegradable membranes including Guidor and S-mambrane were shown to be well tolerated to the surrounding tissue, and were minimal accumulation of inflammatory cell infiltration around the implanted membranes to compare with Gore-tex membrane. Regeneration of defected alveolar bone was initiated from two weeks of membrane implantation and new bone formation was gradually increased from that time. However, pattern of new bone formation on the defected areas of two kinds of biodegrable membranes was almost similar and quite competitive comparing with Gore-tex membrane. These results implicate that bioresorbable membranes should be highly useful tool for guided tissue regeneration of periodontal defects.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.1-10
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• 2008

The purpose of this study was to develop the wireless pH telemetry lasting longer than 24 hours in the mouth to overcome the limits of conventional wire telemetry previously used for salivary and plaque pH measurement, and to assess its effectiveness. We developed a wireless pH telemeter which can measure and store the pH profile data during more than 24 hours. It was composed of intraoral part; pH sensor of antimony electrode, battery and microprocessor for data storage, and extraoral part; control/data receiver and data analyzing software which was newly made for this device. After inspecting wireless electrode for accurate measurement, it was attached to the removable intraoral appliance and delivered to the volunteer who was told to wear except brushing time, retrieved after 24 hours and finally the pH profile data was extracted and analyzed. When compared with conventional wire telemetry, this device showed similar results and induced less discomfort to examinees. The data showed pH changes at same time when examinees ate various scheduled foods and beverages. With this method it became possible to accurately measure pH changes within mouth for long time in accordance with individual's lifestyle, definitely reducing the discomfort inflicted to the examinees' life.

• Journal of the Korean Society of Radiology
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• v.7 no.6
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• pp.419-426
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• 2013

This study was performed in order to suggest the basic informations about the proper oral health babits for kindergarten children, through the investigation of the oral health survey and their oral haelth behaviors. 213 of kindergarten children age 6 were surveyed who has lived at Daegu city and the examined data were analysed by use of spss 18.0 ver.program. The children who had performed the toothbrushing for 3 or 4 times a day, were estimated as high level in voluntary under taking of toothbrushing. It revealed that the low of the caries experience rate in the group of the sabiects who performed toothbrushing at every after meals. On the other hands, both the caries experience index of children who had perfomed toothbrushing with the rolling method and the dental plague index of children who had performed the toothbrushing just the morning time of the oral examination day, wer reveealed as high scores, due to the lack of the abilities to perform the toothbrusing with the proper method. It was needed to educate children for practical performing the toothbrush as well as for traning it with the right way, in order to promote the oral health for kindergarten children.

• Journal of dental hygiene science
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• v.15 no.4
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• pp.399-406
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• 2015

The purpose of this study was to investigate the performance of dental infection control. This survey was performed on 158 of the dental hygienist in certain areas. The research was performed using a self-reported questionnaire and interview method from June to July, 2014. The collected data was analyzed by PASW Statistics ver. 18.0. Guideline of infection management, infection controller, regular infection control training, Sterilization of the handpiece/per head resulted 57~74% for dental hospital. It was higher than 13~20% for dental clinics (p<0.05). Infection control guidelines and vaccination recognition of dental were more performed in dental hospital. Patient's hand hygiene performed, tooth brushing before treatment, cross infection educational experience was less than 20%, research cooperation of medical history was over 90% (p<0.05). Performing rate of the dental hospital workers were investigated higher in protective personal devices, infection control of treatment room. A correlation analysis about institutional support, infection control of dental hygienists, patients with infection control cooperation showed a positive correlation statistically significant. Infection control can be enhanced when the medical staff, the patient, the organization combined cognitive and practice. Dental hygienist is required to recognize and practice the infection control guidelines through continuing education.

• Journal of dental hygiene science
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• v.11 no.5
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• pp.431-436
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• 2011

The aim of this study was to compare the effects of the short-term use of the desensitizing dentifrices marketed in Korea in vitro. Fifty human dentine specimens were wet ground with silicone carbide paper and etched with 6% citric acid for 90 seconds to allow complete opening of the dentinal tubule. Ten specimens from each group were brushed for 50 and 150 strokes with a V8 Cross Brushing Machine(Sabri Co., U. S. A). All the specimens were evaluated by SEM(${\times}3000$). The degree of occlusion of the dentinal tubules was quantified using an image analyzer. The results were analyzed by one-way ANOVA and Tukey's multiple comparisons using Window SPSS. The dentifrices containing nano-carbonate apatite, potassium nitrate and hydroxyapatite showed significantly higher occlusion effects than the other dentifrices after toothbrushing for 50 strokes(p<0.05). The Sensodyne freshmint$^{(R)}$dentifrice showed 34% fewer open tubular areas compared with the Sensodyne original$^{(R)}$dentifrice for 50 strokes. According to the short-term use of desensitizing dentifrices, the dentifrices containing nano-carbonate apatite, potassium nitrate and hydroxyapatite were most effective in occluding the dentinal tubules.

• Journal of dental hygiene science
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• v.8 no.1
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• pp.21-27
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• 2008

This research aims to investigate into company workers' general characteristics and their awareness of the hygiene of the mouth and practice of it, in order to prepare schemes to improve the hygiene of their mouth. The findings of the research are listed in the following: First, the workers have a high level of awareness of the effect of tooth-brushing to prevent periodontal diseases but a low degree of awareness of its effect to prevent decayed teeth and of the necessity of mouth hygienic supplies. Second, they have a high level of awareness of the necessity and importance of scaling, but most of them do not have their teeth scaled periodically. To repeat, they have a high level of awareness of the necessity of dental examination, but not many of them put such awareness of theirs into practice. Third, married workers have a higher level of awareness of the hygiene of their mouth than unmarried ones do. The higher concern they have about the hygiene of their mouth, the more awareness they have of the hygiene of their mouth. Fourth, the higher monthly average income they have, the more frequently they put into practice their awareness of the hygiene of their mouth. And the poorer hygiene of their mouth they have, the more strongly they put into practice their awareness of the hygiene of their mouth.

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.715-725
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• 2009

Objectives : The purpose of this study was to analyze the influence which the professional dental hygiene education has on the knowledge and behavioral change for oral health to the students in the departments of dental hygiene. Methods : 771 students in the first grade and 646 students in the third grade who were attending the departments of dental hygiene from 12 colleges in Korea were surveyed. The self-administered questionnaires were distributed to the students in the colleges during May and asked them to answer the questions and then recovered them on the spot. The collected questionnaires were analyzed by using a SPSS/PC program and the difference of significance depending on the group of the students was tested by Chi-square test or Fisher's exact probability test. Results : In the number of eating snacks by the students during one day, 2-3 times was the highest, irrespectively of the grade. The rate of the students brushing their teeth after snack was higher in the third-grade students(34.8%) than in the first-grade students(20.8%). As the path of acquiring oral health knowledge, all of the first-grade and third-grade students replied that their school classes had impacted them the most. The rate of toothache experience was a higher tendency in third-grade students compared to the first-grade students(p=0.116). The rate of gingival bleeding experience was lower in the third-grade students than in the first-grade students. The rate of oral prophylaxis experience was higher in the third-grade students than in the first-grade students. In the smoking rate, there was lower in the third-grade students than in the first-grade students. The rate of acknowledging smoking hazard to the periodontal health was higher in the third-grade students than in the first-grade students. Conclusions : This study revealed that the third-grade students of dental hygiene departments who were majoring in dental hygiene had a higher perception of oral health than the first-grade students whose the dental hygiene education period was short.

• Journal of Korean society of Dental Hygiene
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• v.12 no.3
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• pp.621-629
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• 2012

Objectives : The purpose of this study was to examine the influential factors for the oral-health practice of adult workers and the relationship of their health-promotion life style to the factors of oral-health practice in an attempt to determine the impact of health-promotion life style. Methods : The subjects in this study were 160 workers who worked in Seoul, North-Jeolla and South-Jeolla Province, and were at the age of 20 and up. The survey was conducted from February 1 to July 20, 2011. Results : As for the relationship of the general characteristics of the workers to the factors of their health-promotion practice, gender made statistically significant differences to toothbrushing female (3.24), and there were statistically significant differences in education/concern according to more than college(2.72) scored higher academic credential(p<0.05). The group of the workers whose health-promotion life style was better in terms of all the toothbrushing(3.35), use of oral hygiene supplies(2.19), regular dental-clinic visit(2.70), dietary control(2.84) and education/concern(3.20) scored higher, and there were statistically significant differences in the factors of education/concern(p<0.05). Their health-promotion life style had an impact on regular dental-clinic visit among the factors of oral-health practice(p<0.05), and there was a positive correlation between health-promotion life style and tooth brushing, dietary control(p<0.05), regular dental-clinic visit, education and concern(p<0.01) the factors of oral-health practice. Conclusions : Workers should be stimulated to get into sound life habits to change their behavior, and they should be urged to improve their preventive health care, to get a dental checkup and ultimately to promote their health as well. Companies should take measures to accelerate the oral health promotion of workers and provide more dental checkup programs for them to be more concerned about their oral health, to promote their oral health and to maintain the best oral health.

• Korean Journal of Health Education and Promotion
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• v.16 no.2
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• pp.157-171
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• 1999

This paper analyzed health practices of students in an university in Chollabukdo Province. It attempted to study how many university students had what kinds of health practices. Furthermore, it tried to find out what are the major problems in health practice among university students. To study health practices of university students, this study sampled 1,469 students randomly. Many of the students had poor practices of teeth care. In tooth-brushing, many students (35.8%) brushed their teeth before breakfast in the morning. Most of the students (95% or more) visit dental clinic only when they had problem(s) in their teeth. For weights, there exists a great gap between perception and BMI (Body Mass Index), especially among female students. Among the female students who perceived their weights were above average, 96.4% of them were normal according to BMI. Many of the students were drinking greater amount of alcohol than safe amount suggested by the National Health and Medical Research Council of Australia. The proportion of the students drinking harmful or hazardous amount of alcohol were 79.5% of the male students and 74.9% of the female students. It suggests that health promotion fund or tax need to be levied on alcohol to frustrate unhealthful drinking. More than half (59.0%) of the male students and about 6.0% of the female students were smoking cigarettes. The smoking initiation ages were 17.8 for male and 18.2 for female students. It means that many of the students started smoking in their junior high or high schools. It implies that smoking prevention and smoking cessation programs need to be emphasized in these schools. For perception on sex, 27.8% of the male students and 60.9% of the female students thought to keep their virginity before their marriage. The female students were more conservative in perception on sex. The average number of sexual intercourses per year of male students was 17.0 times with their lovers, 7.9 times with prostitutes, and 7.0 times with maids. The female students had sexual intercourses 5.0 times with their lovers and 4.0 times with waiters per year. The proportion of students who had experience of sexual intercourse with homosexual partners was 1.0%. The finding this study was that the university students were vulnerable to poor health practices. It is suggested that public health intervention program be provided for university students to keep them in good healthy lifestyle.