• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.1131-1137
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• 2013

This paper introduces novel a two-phase permanent magnet BLDC (PMBLDC) motor with both an asymmetric tooth and an auxiliary tooth in order to improve the dead point, efficiency and torque ripple. To calculate the merits of introducing each of the asymmetric tooth and the auxiliary tooth, characteristic analysis is performed respectively using finite element method (FEM). To maximize performance, we propose a novel model which combines the asymmetric tooth and the auxiliary tooth. To maximize the efficiency of the novel model, an optimal design is processed using the Kriging method and a genetic algorithm. Finally, an experiment is used to confirm the initial and optimal design results.

• Journal of dental hygiene science
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• v.9 no.1
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• pp.121-127
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• 2009

A comparative analysis was conducted through this study on tooth brushing and a use of auxiliary oral hygiene devices for oral hygiene for 287 S Health College students some of whom major dental hygiene and some of whom don't relate to the department, and then has drawn out the results as below. 1. Relating to the frequency of tooth brushing, 2-3 times a day was the utmost case in both departments(p < 0.05). 2. In use of toothbrush bristle, the students of dental hygiene department used medium bristle(51.2%), while the student of other department used soft bristle(51.5%)(p > 0.05). 3. In the term of tooth brush used, 2~5 months was the utmost case in both departments(p > 0.05). 4. In tooth- brushing method, all the student of both departments said they knew how to do it(p > 0.05). 5. In the acquisition of tooth brushing methods, the students of dental hygiene acquired it from dentistry 44.4%, and the students of other department from TV or Radio 47.5% (p > 0.05)which was a quite high rate. 6. In reference to recognition level on auxiliary oral hygiene devices, dental hygiene students said Yes 79.8%, and the other side students said No 63.9%(p < 0.05). In reuse of auxiliary oral hygiene devices, a great number of students of both departments said No (p < 0.05). 8. In reference to the chance to use auxiliary oral hygiene devices, 58.1% of dental hygiene students chose them with their own judgement, and 37.8% of other department students recommended by dentist's offices(p < 0.05). 9. Relating to the reason for not using auxiliary oral hygiene devices, 38.9% of the dental hygiene students said it's bothersome, and 56.7% of the other department students said they didn't know about these things(p < 0.05). 10. In the recognition level of dental floss, in knowing the way to use it, whether or not of using it, the students of both department showed a significant difference (p < 0.05). 11. In the recognition level of floss holder and the yes or not of using it, there was an insignificant difference(p > 0.05), while in understanding of it, there was a significant difference(p < 0.05). 12. Relating to the recognition level of electric tooth brush, yes or no of using it, there wasn't a significant difference(p > 0.05). 13. In the cognition level of rubber stimulator, yes or no of using it, there wasn't much difference, while in understanding to use it, there was a significant difference(p < 0.05). 14. In the understanding level of water pik, yes or not of using it, there wasn't a great deal of difference(p < 0.05), but in inquiry of whether or not of using it, there was no difference (p > 0.05), 15. In the understanding level of tongue scraper, whether or not of using it, there wasn't much difference(p > 0.05), but in understanding to use it, there was a great deal of difference(p < 0.05). 16. In the recognition of garglin, understanding of it, and whether or not of using it, the two departments didn't show a significant difference(p < 0.05).

• The Journal of the Korean dental association
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• v.44 no.2 s.441
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• pp.123-132
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• 2006

Patients who have impacted tooth are found commonly in orthodontic treatment. Although it is difficult to find the cause of impacted teeth, the most common, causes are prolonged retention of the deciduous teeth, trauma, aberrant sequence of eruption, lack of space and deficiency of Vitamin D. Impacted teeth may lead to esthetic and functional problems and root resorption of adjacent teeth, so we should treat it as soon as possible. Commonly used treatment method is the following: After surgically uncovering of the impacted teeth, a bond of orthodontic appliance is established, and orthodontic traction is started with a removable or fixed appliance. We used the modified lingual arch with a soldered auxiliary appliance in lingual arch for traction of lower impacted teeth. The modified lingual arch could control the magnitude and direction of the applied force with one-arch treatment, and also could give continuous force to impacted tooth without patient patient cooperation. We achieved good results with the modified lingual arch.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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• pp.77-83
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• 2013

Orthodontics is a branch of dentistry that is concerned with the study and treatment of malocclusion, which may result from tooth irregularities, disproportionate jaw relationships, or both. Orthodontic devices consist of brackets, archwire connected to each bracket, and bends and hooks for auxiliary functions. Basically, orthodontics involves the interaction of brackets and archwire. It should be noted that uncontrolled tipping can occur due to unwanted movement of the teeth. The bending of an archwire can control the angle of an archwire and the rotation of a tooth. In this study, we predict the relationship between the bending angle of an archwire and the rotation of a tooth using the Kriging interpolation method. Also, we calculate the angle of an archwire that occurs at the minimum value of tooth rotation.

• Progress in Medical Physics
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• v.26 no.1
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• pp.52-58
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• 2015

The automated dental cavity detection program for a new concept intra-oral dental x-ray imaging device, an auxiliary diagnosis system, which is able to assist a dentist to identify dental caries in an early stage and to make an accurate diagnosis, was to be developed. The primary theory of the automatic dental cavity detection program is divided into two algorithms; one is an image segmentation skill to discriminate between a dental cavity and a normal tooth and the other is a computational method to analyze feature of an tooth image and take an advantage of it for detection of dental cavities. In the present study, it is, first, evaluated how accurately the DRLSE (Direct Regularized Level Set Evolution) method extracts demarcation surrounding the dental cavity. In order to evaluate the ability of the developed algorithm to automatically detect dental cavities, 7 tooth phantoms from incisor to molar were fabricated which contained a various form of cavities. Then, dental cavities in the tooth phantom images were analyzed with the developed algorithm. Except for two cavities whose contours were identified partially, the contours of 12 cavities were correctly discriminated by the automated dental caries detection program, which, consequently, proved the practical feasibility of the automatic dental lesion detection algorithm. However, an efficient and enhanced algorithm is required for its application to the actual dental diagnosis since shapes or conditions of the dental caries are different between individuals and complicated. In the future, the automatic dental cavity detection system will be improved adding pattern recognition or machine learning based algorithm which can deal with information of tooth status.

• The Journal of the Korean dental association
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• v.37 no.8 s.363
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• pp.608-613
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• 1999

During diagnostic process of the orthodontic patients, it is not unusual to find palatally erupted canines. Palatally erupted canines are related with the positional abnormalities rather than the tooth size/arch-length discrepancies. It is very important to conserve the original arch shape during traction of palatally erupted canines to their proper position. On the following case, the patient was diagnosed as malocclusion with palatally erupted canines, and were treated by 0.9mm auxiliary arch wire during traction of ectopic canines for maintenance of the original arch shape.

• Journal of dental hygiene science
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• v.6 no.2
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• pp.93-99
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• 2006

This study was carried out to investigate practical application status of oral hygiene devices through making a survey of labor of the D industrial company-about carefully curing oral disease in home, the status of practical application of tooth brush, the status of practical application of fluoridated toothpaste, status of practical application of auxiliary oral hygiene devices, a motive use or unuse of auxiliary oral hygiene devices. 1. In home, carefully curing oral disease is dental caries(62.4%). 2. Status of practical application toothbrush showed the highest user ratio of mideum size(79.6%). 3. Showed the highest user ratio of horizontal plane toothbrush(73.5%). 4. Answerd don't take a prudent attitued in choice of fluoridated toothpaste(73.5%). 5. In the status of reconition of oral hygiene devices, showed the highest user ratio of eletric toothbrush(77.0%). 6. In the status of reconition of auxiliary oral hygiene devices, showed the highest user ratio of wooden wedge stimulator(89.4%)and gargle liquid(84.5%). In using of oral hygiene devices, showed the highest user ratio of electric toothbrush(13.3%), toohbrush for periodontal patients(2.7%). In using of auxiliary, wooden wedge stimulator (58.4%)and gargle liquid(41.2%). In effect using of oral hygiene devices showed the highest user ratio of denture brush(50.0%)and eletric toothbrush(43.3%), in effect using of auxiliary oral hygiene devices showed the highest user ratio of water pick(80.0%) and dental floss(75.8%). 6. A motive of the use auxiliary oral hygiene device is choice by oneself through TV, advertisement, public information(57.6%), and the reason-they don't use of auxiliary oral hygiene devicebecause of they don't know proper to them the kind of auxiliary oral hygiene device.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.12
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• pp.7-14
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• 2019

A marine turning gear controls the position of the piston-crank mechanism by rotating the flywheel of the marine engine at a low speed, which is the main auxiliary machine that enables the disassembly and maintenance of the engine. In this study, the safety factor for surface durability and tooth bending strength was improved by the design modification of the marine turning gear based on the spur planetary gear. Angular velocity, torque, and efficiency of the turning gear were measured using a reliability evaluation tester, and a multibody dynamics model for analysis corresponding to the test results was developed. Finally, it was confirmed that the design improvements improved the tooth surface damage of the sun gear in the 3^rd reduction stage.

• Journal of dental hygiene science
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• v.23 no.3
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• pp.208-215
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• 2023

Background: Dental caries in preschool children can cause early loss of teeth, reduced masticatory function, malocclusion, and speech disorders, making oral care for preschool children essential. However, because children have a poor ability to perform oral hygiene by themselves, educational tools that help establish correct oral health behaviors are required. This study evaluated the effect of toothbrushing application for kids on dental plaque removal and toothbrushing interest in preschool children. Methods: Seven 5-year-old children enrolled in a daycare center participated in the evaluation, and the same children participated in the experiment twice a week. The Pokémon Smile application (App) was used as an auxiliary application for tooth brushing, and the degree of dental plaque removal on the tooth surface was evaluated by quantitative light-induced fluorescence-digital imaging. After the experiment, children's toothbrushing preferences were investigated through interviews. Results: The levels of AREA R30 and AREA R70 measured after the children's toothbrushing as usual decreased compared to those before toothbrushing; however, the change was not significant. The levels of AREA R30 and AREA R70 measured after using the Pokémon Smile App were significantly reduced compared to those before toothbrushing. Children's interest in brushing their teeth increased by 28.59% after using the Pokémon Smile App. Conclusion: The toothbrushing application for kids effectively removes dental plaque by helping preschool children brush their teeth. It also increased preschool children's interest in tooth brushing. Therefore, an oral health education application would be useful for children who need to develop correct oral care methods and habits.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.45-53
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• 2012

The purpose of this study is to work out plans to reduce oral malodor by carrying out effective methods. In the research, 17 volunteers were selected from the students at Sahmyook Health University's Dental Hygiene Dept. in order to measure the effects of reduction of oral malodor. The results are as follows. 1. As time passes, both the control group and the experimental group proved the effects of the reduction of oral malodor for 20 minutes after the experiment(p<0.05). 2. The experimental group with tooth-brushing showed a statistically significant difference compared with the control group from a lapse of 5 minutes after the experiment to 20 minutes(p<0.05). 3. The experimental group with tongue cleaner did not prove a statistically significant difference compared with the experimental group with toothbrushing( p>0.05). 4. The experimental group in which participants took a candy showed a statistically significant difference compared with the control group after 5 minutes(p<0.05). 5. The experimental group with chewing a gum proved a statistically significant difference compared with the control group for 10 minutes(p<0.05). Using a washing implement of the tongue, taking a candy, and chewing a gum proved the same effect of reducing foul breath as in the case of operating a tooth-brushing. This experiment proves that taking a candy or extending time of chewing a gum was effective in a short time, and using a tongue cleaner or chewing a gum for 5 minutes was a useful method for reducing oral malodor if not operating a tooth-brushing.