• Journal of Periodontal and Implant Science
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• v.48 no.5
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• pp.295-304
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• 2018

Purpose: This study was undertaken to evaluate the clinical and microbiological effects of an erythritol powder air-polishing device (EPAP) as a supplement to scaling and root planing (SRP) therapy in patients with moderate chronic periodontitis. Methods: Clinical and microbiological evaluations were performed at 21 sites treated with SRP (control) and 21 sites treated with SRP+EPAP (test). All examinations were performed before treatment, 1 month after treatment, and 3 months after treatment. Results: There were no significant clinical differences between the test group and the control group. Microbiological analysis revealed that the relative expression level of Porphyromonas gingivalis was significantly lower in the test group than in the control group at 1 month after treatment. Clinical and microbiological results showed improvements at 1 month compared to baseline; in contrast, the results at 3 months after treatment were worse than those at 1 month after treatment. Conclusions: In this study, both SRP and SRP+EPAP were clinically and microbiologically effective as non-surgical periodontal treatments. In particular, the SRP+EPAP group showed an antimicrobial effect on P. gingivalis, a keystone bacterium associated with the onset of chronic periodontitis, in a short-term period. Periodic periodontal therapy, at intervals of at least every 3 months, is important for sustaining the microbiological effects of this treatment.

• Journal of Periodontal and Implant Science
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• v.43 no.2
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• pp.101-105
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• 2013

Purpose: The present study aimed to measure root surface roughness in teeth with periodontitis by a profilometer following root planning with ultrasonic and hand instruments with and without erbium-doped yttrium aluminium garnet (Er:YAG) laser irradiation. Methods: Sixty single-rooted maxillary and mandibular teeth, extracted because of periodontal disease, were collected. The crowns and apices of the roots were cut off using a diamond bur and water coolant. The specimens were mounted in an acrylic resin block such that a plain root surface was accessible. After primary evaluation and setting a baseline, the samples were divided into 4 groups. In group 1, the samples were root planned using a manual curette. The group 2 samples were prepared with an ultrasonic scaler. In group 3, after scaling with hand instrumentation, the roots were treated with a Smart 1240D plus Er:YAG laser and in group 4, the roots were prepared with ultrasonic scaler and subsequently treated with an Er:YAG laser. Root surface roughness was then measured by a profilometer (MahrSurf M300+RD18C system) under controlled laboratory conditions at a temperature of $25^{\circ}C$ and 41% humidity. The data were analyzed statistically using analysis of variance and a t-test (P<0.05). Results: Significant differences were detected in terms of surface roughness and surface distortion before and after treatment. The average reduction of the surface roughness after treatment in groups 1, 2, 3, and 4 was 1.89, 1.88, 1.40, and 1.52, respectively. These findings revealed no significant differences among the four groups. Conclusions: An Er:YAG laser as an adjunct to traditional scaling and root planning reduces root surface roughness. However, the surface ultrastructure is more irregular than when using conventional methods.

• Journal of dental hygiene science
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• v.1 no.1
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• pp.39-45
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• 2001

This study is based on the survey conducted on handicaps in randomly chosen 6 welfare facilities and medical institutions located in Seoul and Kyonggi-do. This survey has been conducted from September 20 and October 23, 1999. The results of this study are as follows: (1) 49.7% of individuals have answered that their dental health are not well maintained. (2) The number of brushing activity per day varied according to different physical and mental condition of each individual. (p<0.05) (3) 56.7% of people have answered that they have no experience with scaling. (4) 58.9% of people have answered that they have experienced toothache and gum bleeding problem. (5) 64.4% of individual have answered that they would like to attend seminars on maintaining dental health. (p<0.05) (6) 65.1% of individual infrequently visit to dental facilities. (7) 41.6% of individual possess health care card. (8) 61.8% have answered that disabilities and dental health are closely related. (p<0.05)

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.6
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• pp.47-52
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• 2002

The wavelet functions are originated from scaling functions and can be used as activation function in the hidden node of the network by deciding two parameters such as scale and center. In this paper, we would like to propose the mixed structure. When we compose the WNN using wavelet functions, we propose to set a single scale function as a node function together. The properties of the proposed structure is that while one scale function approximates the target function roughly, the other wavelet functions approximate it finely. During the determination of the parameters, the wavelet functions can be determined by the global search algorithm such as genetic algorithm to be suitable for the suggested problem. Finally, we use the back-propagation algorithm in the learning of the weights.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.1109-1116
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• 2005

The purpose of this study was to observe the effects of periodontal therapy, including nonsurgical periodontal therapy with azithromycin, surgical therapy, and maintenace therapy on the drug-induced gingival enlargement, by means of measuring gingival thickness. The test group of 18 patients with drug-induced gingival enlargement received scaling, root planing with azithromycin for 5 days, with or without surgical periodontal treatment. The control group of 18 patients who had not taken any medication, received scaling and root planing, with or without surgical periodontal treatment. Both groups received supportive periodontal therapy every 3 months for 2 years. The mean period of total treatment is 32 months in the test group and 31 months in the control group. The thickness of the buccal gingiva was measured using an ultrasonic device of $SDM^{(R)}$(Krupp Corp., Essen, Germany). The results revealed that the test $group(1.21{\pm}0.51mm)$ showed statistically thicker buccal gingiva than the control $group(1.01{\pm}0.3mm)$. In the test group, the buccal gingiva was thickest on 2nd molars and was thinnest on canines of both dental arches. In the control group, the buccal gingiva was thickest on central incisors in the maxilla and 2nd molars in the mandible, while the thinnest areas were on canines in the maxilla and 1st premolars in the mandible. It would be concluded that the periodontal treatment with azithromycin aids in decreasing the degree of the gingival enlargement but cannot prevent the recurrence completely.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.77-84
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• 2008

Experimental study was conducted to clarify the importance of buoyancy effects in laminar lifted flames which have been well understood by cold jet similarity theory. To evaluate buoyancy effects, lifted flame behaviors were systematically observed in methane and propane lifted flames diluted with He as changing the fuel nozzle diameter from 0.1 to 6 mm. Important physical parameters such as fuel strength, flame stretch and flame curvature, which were derived through simple physical scaling laws, were estimated. It is experimentally proven that buoyancy effects are important in relatively large fuel nozzle diameter and large fuel dilution with He. The results of Chen et al., which displayed the existence of stably lifted flames for 0.5

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.824-835
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• 2009

Objectives : The purpose of this study was identified about oral health status and oral health needs of elderly. Moreover this study would be based further research of development of oral health in elderly. Methods : This study was undertaken to determine the oral health status and the need of oral management of over 65years elderly who were with dental prosthesis in elderly welfare center and Kyung Ro Dong in Kyung Bok and Kyung Nam. The results were as follows. Results : The sample was 200 participants. The demographical characteristic were that 74.0% of participant was female, 29.0% of participant was 75~79 years old, 42.5% of participant was under elementary, and 45.5% of participant was living alone. 43.7% of participant was pain from muscle-skeletal disease, 37.1% of participant was cardiac-vascular disease, and 31.1% of participant was ophthalmic disease. In oral health status, 54.5% of participant was partly artificial tooth and 45% of participant was whole artificial tooth. 78.0% of participant used under 10 years with partly artificial tooth and only 27.4% were satisfaction with artificial tooth. 83.5% of participant used under 10 years with whole artificial tooth and only 26.4% were satisfaction with artificial tooth. In the oral health status of partly artificial tooth, the average of toothbrush was 2 times, 42.2%. The majority method of toothbrush was 'their own freely' 55.0%. The time of toothbrush was 'after meal' 81.8%. The study result showed that majority participant didn't experience of tongue brush, regular examination, scaling, and oral health education. In the need of oral management with the whole artificial tooth, the participant who used longer artificial tooth was significantly higher about artificial irrigation and the method of management(p<.05). The need of participant who answered 'don't gum massage', was higher of xerostomia treatment(p<.01) and halitosis treatment(p<.05). In the need of oral management with the partly artificial tooth, the participant who used longer artificial tooth was significantly higher about regular examination(p<.01), oral cavity massage(p<.05), scaling(p<.05), dental caries treatment(p<.01). The need of participant who answered 'don't satisfaction with artificial tooth' was higher of regular examination and scaling(p<.05). Conclusions : Oral management needs of elderly who kept artificial tooth or denture required were regular dental examination, xerostomia management, management of artificial tooth and irrigation, and management of bad breath. This results meaned the oral health intervention program for elderly was developed regularly.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.10
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• pp.1217-1224
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• 2014

This paper provides a practical scaling method to solve an old problem for scaling and developing the speed and resistance of a model to full-scale submarine in fully submerged underwater test. In every experimental test in towing tank, water tunnel and wind tunnel, in the first step, the speed of a model should be scaled to the full-scale vessel (ship or submarine). In the second step, the obtained resistance of the model should be developed. For submarine, there are two modes of movement: surface and submerged mode. There is no matter in surface mode because, according to Froude's law, the ratio of speed of the model to the full-scale vessel is proportional to the square root of lengths (length of the model on the length of the vessel). This leads to a reasonable speed and is not so much for the model that is applicable in the laboratory. The main problem is in submerged mode (fully submerged) that there isn't surface wave effect and therefore, Froude's law couldn't be used. Reynold's similarity is actually impossible to implement because it leads to very high speeds of the model that is impossible in a laboratory and inside the water. According to Reynold's similarity, the ratio of speed of the model to the full-scale vessel is proportional to the ratio of the full-scale length to the model length that leads to a too high speed. This paper proves that there is no need for exact Reynold's similarity because after a special Reynolds, resistance coefficient remains constant. Therefore, there is not compulsion for high speeds of the model. For proving this finding, three groups of results are presented: two cases are based on CFD method, and one case is based on the model test in towing tank. All these three results are presented for three different shapes that can show; this finding is independent of the shapes and geometries. For CFD method, Flow Vision software has been used.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.343-350
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• 2016

To prepare a method for improving the oral health-related quality of life for Chinese foreign students by examining the oral health care behavior affecting the oral health-related quality of life, a self-administered survey was conducted with 236 Chinese foreign students at an university located in Jeonbuk during April 2 -May 5, 2013. The results showed that 65.3% had not visited the dentist within one year, 82.6% had not received scaling within one year, and 68.2% had not received oral health education. In regards to the OHIP-14 according to the general characteristics, there was a significant difference in the school year, health insurance enrollment status and overseas study life satisfaction (p<0.05). In regards to the OHIP-14 according to the oral health care behavior, there was a significant difference in the subjective oral health condition, the experience of having visited a dentist within one year and an experience of having received scaling (p<0.05). As for the influencing factors on the oral health-related quality of life, they were found to be the subjective oral health condition and the experience of having received scaling within one year (p<0.05). For the purpose of helping Chinese foreign students to conveniently use medical institutions when oral health-related problems arise, there is a need for a translated version of the guidebook in their native language, the availability of medical professional interpreters, the availability of a university level oral health service center, and practical oral health education to enhance oral health.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.461-468
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• 2014

This study was to figure out the influence of oral health behavior and periodontal status on their OHIP-14. Explained to 255 people who visited the scaling center of Dental Hygienics of a college in Gyeongbuk from March 7th to June 13th 2014 and it was agreed to perform. Result of dental plaque and calculus rate of those with no TBI were high; the less frequent do they teeth brushing the higher were their rate of dental plaque, bleeding and calculus, while their OHIP-14 was low. The rate of calculus of whom with no education on dental floss use and who do not use dental flosswas high. The more powerful for those with higher rate of dental plaque; while the lower was the rate of calculus the higher was OHIP-14. Therefore, the more do they brush their teeth and the lower are the rate of their calculus, the more positively has it been figured out to influence on the quality of their life of oral health. Consequently, public health program should be developed to educate them on the necessity of scaing on a regular basis and the cause calculus of occurrence, as well as a media through which they can easily participate in the program.