• Journal of Oral Medicine and Pain
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• v.30 no.4
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• pp.411-426
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• 2005

The purpose of this study was to investigate the effects of occlusal condition and clenching level on the mandibular torque rotational movement. For this study, healthy 14 men without any symptoms and signs of temporomandibular disorders were selected. Mandibular torque rotational movement was observed in each circumstance of combination of three occlusal conditions such as natural dentition, with wafer of 3.6 mm thickness, and wafer with resin stop of 14 mm thickness total during hard biting of bite stick at maximum voluntary contraction(MVC) and 50% of MVC level of surface EMG activity of masseter muscle. Electromyographic activity and mandibular torque rotational movement were observed using BioEMG and BioEGN in $BioPak^{(R)}$ system. Each biting movement in each circumstance was composed of clenching one time and hard biting of wooden stick two times. The observed items were opening distance, velocity and amount of torque rotational movement in mandibular movement, and the data were statistically processed with $SPSS^{(R)}$ windows (ver.10.0). The results of this study were as follows: 1. There were no differences in the mandibular movement distance between those value in both biting sides, and between those in both clenching forces, but the mandibular velocity showed a different results by clenching force. For the amount of torque rotational movement, there were no difference in the value of the frontal plane but some significant difference was in the value of the horizontal plane by biting side. 2. The mandibular movement distance and the mandibular velocity in both planes were higher by maximum voluntary contraction than those by half maximum voluntary contraction, and amount of torque rotational movement in the horizontal plane was also increased by maximum voluntary contraction. 3. The opening distance in both planes were decreased with the increase of vertical dimension of occlusion, namely, by the occlusal appliances, and this pattern was also showed in the mandibular velocity in case of hard biting by maximum voluntary contraction. However, the amount of torque rotational movement were not different by the increase of vertical dimension of occlusion. 4. The value of angle and distance of the torque rotational movement in the hard biting of wooden stick were generally higher than those in the clenching without wooden stick in both planes without regard to occlusal conditions and/or clenching forces.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.4
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• pp.731-752
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• 1995

This study was performed to research the changes of masticatory system subsequent to randomly increasing the vertical dimension. The subjects were twenty seven persons, twenty two men and five women, with a mean age of 24.3(age ranged from 22 to 26). The subjects had a complete or almost complete set of natural teeth and reported no subjected symptoms of pain or dysfunction in the masticatory system. The occlusal splint increased vertical dimension was made on semiadjustable articulator. The subjects were randomly divided to three groups according to the vertical dimension, at which the occlusal splint was made. Group I occlusal splints were made at 2mm form the occlusal vertical dimension, group II occlusal splints at 5mm, group III occlusal splints at 8mm. The occlusal splints were almost weared for 2 weeks except meal-time. Clinical examination, muscle activity, changes of free-way space, movement of mandible and articular condyle were recorded and analyzed by means of biopak system(Bioresearch Inc, Millwakee Wisconsin.) and radiograph. 1. In clinical examination, various symptoms were reported by all subjects immediately after the placement of occlusal splint. At the end of experiment, symptoms were lasted by 1 subject in Group I, 2 subjects in Group II, 6 subjects in Group III. At the other subjects, the most of symptoms were disappered within 2-4 days after the placement of occlusal splints. 2. The average free-way space before the startof experiment was 1.77mm in all twenty seven subjects. Immediately after the placement of occlusal splints, 0.67mm at Group I, 0.49mm at Group II, 0.41mm at Group III, At 2 weeks after the placement of occlusal splint 0.93mm, 0.79mm, 0.78mm each other, 1.94mm, 1.77mm, 2.3 mm at immediately after the removal of occlual splint. At 1 week after the removal of occlusal splint, free-way space was recovered to the pre-experimental state 3. In cephalometric radiograph, following either the placement or the removal of the occlusal splints, the movements of mandible in an antero-posterior direction were not statistically significant(p>0.05). 4. In transcranial radiograghs of TMJ, 1 week after the placement of occlusal splint the movement of most superior position on condyle in all group shoed antero-inferior position than before the experiment(p<0.001) and also showed antero-inferior position in mandibular postural rest position than in certric occlusion(p<0.001). Following either the placement or the removal of the splints, the amount of movement of most superior position on condyle was group III. group II and group I in order(p<0.001). 5. In anterior temporal and superficial masseter muscle, muscle activity at postural rest position decreased at 2 weeks after the placement of occlusal splint in group I and group II (p>0.05), but significantly increased in group III(p<0.001). At 1 week after the removal of the occdusal splint, muscle activity at postural rest position was recovered preconditional state 6. In anterior temporal and superficail masseter muscle, muscle activity at clenching in all group was significantly decreased after placement of the occlusal splint, slightly increased during experimental period and recovered to the original state at 1 week after removal of the occlusal splint. But was not statistically significat(p>0.05)s.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.487-496
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• 2021

Full mouth rehabilitation is re-organizing the occlusion of the remaining teeth and missing teeth considering the functions, esthetics, and neuromuscular harmony. With the loss of multiple teeth, the patient's occlusal plane gradually collapses and the vertical dimension can be reduced. Since reduced vertical dimension can be a potential etiology of the temporomandibular joint and masticatory muscles, prosthetic restoration with increased vertical dimension is required. This case report is about a 68 years old patient with vertical dimension loss due to worn dentition and multiple loss of teeth. In this case, the loss of vertical dimension is assessed carefully using the digital dentistry technology. Using CAD software in digital analysis step, the occlusal plane was established and evaluated using several criteria. Orienting the position of the bone and teeth using CBCT image, patient's condition was visualized in 3 dimension and treatment planning was possible virtually. The information that matches the patient's condylar position with the articulator, which is the virtual face bow, is reproduced on the actual articulator, and evaluated again. After the evaluation, provisional prosthesis was fabricated and it was confirmed that the patient adapts without any abnormality. This was implemented as a final prosthesis. As a result, the patient obtained satisfying results, utilizing the benefits of digital dentistry technology and traditional methods.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.532-542
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• 2007

The purpose of study was to review the transition of dentition according to the evolution of man to know the background of the dental problems like hypodontia and malocclusion. Man is Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Primates, Suborder Haplorrhini, Superfamily Hominoidea, Family Hominidae, Genus Homo, Species Sapiens by taxonomy. The first hominid was Australopithecus which appeared c. 4 millions of years ago and showed bipedalism and distinct dentition. Homos began with H. habilis who appeared c. 2.5 millions of years ago and made stone tools, and then H. erectus and H. neanderthalensis appeared and disappeared until H. sapiens came. The dental formula of primitive mammalians which was I3 C1 P4 M3 changed to I2 C1 P4 M3 of primitive primates, to I2 C1 P3 M3 of Haplorrhini, and to I2 C1 P2 M3 of hominoids. That of H. sapiens is changing to I2 C1 P2 M2.The box type dentition of hominoids changed to the omega type dentition of Australopithecus, and to the parabolic type of H. sapiens. The size of teeth decreased continually, especially the canine and sexual dimorphism. The dentition moved backward and downward to the cranial crown according to the increase of the brain and decrease of the jaws. It was suggested that the change of diet to the starchy foods, food processing, and the development of cooking reduced the necessity of mastication and caused the change of dentition. The future of H. sapiens who is quite a new species in the earth histroy and is now causing the mass extinction of other species is hard to see. It seems that hypodontia and malocclusion are related to the dentition change according to the evolution of man and is likely to increase.

• Journal of Korea Technology Innovation Society
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• v.12 no.1
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• pp.165-188
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• 2009

The major purposes of the research are to see the underlying disciplines of technology innovation management which contribute to Korean research. To do that, we employed author cocitation analysis which has been proved to be robust. We compiled all the citations of two major Korean journals between 1993 and 2006. We also included up to 3rd author, which makes a cocitation analysis more comprehensive, compared with the previous analysis for the first author only. We identified 239 authors who have more than 10 citations. From the cocitation combinations based on the 239 authors, we selected and analyzed 100 most cocited authors. Out of 100 authors a group of 23 authors who command both higher citations and cocitations were chosen for detailed analysis. The results show that the average number of publications is 22.2, the average number of citations to them is 58.5, and the average number of citations to a publication is 2.6. Also, the average number of cocitations is around 10 times that of citations. The results indicate that there are six major disciplines: Technology/Innovation, Management of Technology, Economics of Technology, Development, Valuation of Technology, and Growth. Noteworthy points are the following. 1) Most of the members of the technology management group are management scholars, and the groups of economics of technology and growth are economists, while the groups of technology innovation and development group are not represented by specific disciplines. 2) Considering the groups overall from the traditional academic disciplines, the main branches are management and economics. 3) The valuation of technology group consists mostly of Korean researchers.

• Journal of Oral Medicine and Pain
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• v.31 no.1
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• pp.101-111
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• 2006

Temporomandibular disorders (TMD) is a collective term embrassing a number of clinical problems that involve the masticatory musculature, the Temporomandibular joint and associated structures, or both. The prevalence of signs and symptoms associated with TMD can be best appreciated by examining epidemiologic studies. But domestic epidemiologic studies about sex, history, chief complaint, diagnosis were not sufficient comparing with foreign countries. The results obtained as follow. 1. The number of visiting patients were 6500 and mean age was 34.06 year (Male's mean age was 33.15, Female's 34.62). In the age of patients, there was no significant difference between sex. 2. There are most patients who were referred by dentist (80.07%). Most diagnostic group was arthrogenous TMD group and followed by myogenous TMD, soft tissue disease. 3. There was strong interaction between diagnostic groups and chief complaint. 4. There was little pain difference between right and left sides. Male mainly had pain onset under 6 month, but female had pain onset more than 6 month. 5. The number of patients who had joint sound history were 3445 (53.15%). There was no significant difference of pain onset between sex. Clicking sound was most among joint sounds which happened to patients. 6. In analyzing the parafunctional habit, male mainly had bruxism, but female had clenching habit.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.29 no.2
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• pp.103-117
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• 2020

A beautiful smile has a great impact on the quality of life. It gives you confidence, and makes you function with a positive attitude, which will eventually bring the joy and happiness to daily lives. As dental practitioners, our mission is to bring back the bright smile of the people who come to see us. Restoring masticatory function is one thing but one should always remember that the esthetics should always come first in any kind of restorative procedures. When treating complex rehabilitation cases, treatment planning is probably the most important step before you start any dental procedures. Obviously, esthetics should be the ultimate goal of the treatment and one should approach a case step by step to achieve an optimal result. For the past few years, "digital smile design" has been introduced in the field of dentistry. It can be applied by using various methods and tools. In this article, a very basic form of 2-dimensional digital smile designing was utilized to treat a complete mouth rehabilitation case. We will discuss how the DSD concept can be applied to your daily practice with a simple photograph and photoshop.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.197-210
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• 2022

Entomopathogenic fungi can be used to control a variety of sucking and chewing insects, with little effect on beneficial insects and natural enemies. Approximately 170 entomopathogenic fungal insecticides have been registered and used worldwide, with the recent focus being on the mode of action and mechanism of insect-fungal interactions. During the initial period of research and development, the industrialization of entomopathogenic fungi focused on the selection of strains with high virulence. However, improvement in productivity, including securing resistance to environmental stressors, is a major issue that needs to be solved. Although conidia are the primary application propagules, efforts are being made to overcome the limitations of blastospores to improve the economic feasibility of the production procedure. Fungal transformation is also being conducted to enhance insecticidal activity, and molecular biology is being used to investigate functions of various genes. In the fungi-based pest management market, global companies are setting up cooperative platforms with specialized biological companies in the form of M&As or partnerships with the aim of implementing a tank-mix strategy by combining chemical pesticides and entomopathogenic fungi. In this regard, understanding insect ecology in the field helps in providing more effective fungal applications in pest management, which can be used complementary to chemicals. In the future, when fungal applications are combined with digital farming technology, above-ground applications to control leaf-dwelling pests will be more effective. Therefore, for practical industrialization, it is necessary to secure clear research data on intellectual property rights.

• The Journal of Korean Philosophical History
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• no.28
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• pp.387-415
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• 2010

This article examines Zhu Xi(朱熹)'s theory of I-Qing(易經) present in Yi Xue Qi Meng. Zhu Xi aims to establish a novel Confucian theory of I-Qing, examining the study of I-Qing in Han Dynasity and the Taoist theory of I-Qing. To this end, he embraces Shao Yong(邵雍)'s theory of Xian Tian. Adapting the notion of Xian Tian(先天) as developed by Shao, he completes the Image-Number(象數) Theory of Hetu-Luoshu(河圖洛書). While discussing Hetu Luoshu, Zhu Xi argues that the Image and Number are not merely a form of prognostication, but a medium that reveals the principles of the nature and the sagely ways of mind. In addition, by studing I-Zhuan(易傳) in authoring Yi Xue Qi Meng, Zhu Xi maintains that the notions of Image and Number as he understands were to be approved by Confucius. This leads to the unification of Sho Yong's Tai-Ji(太極), Zou Dun Yi(周 敦頤)'s Tai-Ji, and Tai-Ji in Hetu. Through this work, Zhu Xi attempts to construct a systematic philosophy that straddles ontology and value theory, while identifying Li (理) with Xiang (象) and Shu (數). The Image-Number Theory of Hetu-Luoshu has replaced numerous theories of Image and Number at the time of Zhu Xi. Based on this theory, he restores the method of divination as presented in Xi CI Zhuan(繫辭傳). By successfully applying his theory of Image and Number to interpreting a number of recorded examples of divination during the Spring and Autumn period and the Warring States period, Zhu Xi demonstrates that his theory is not only an abstract metaphysical theory, but also can function as an adaptable method of divination.

• Korean Association for Visual Culture
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• v.35
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• pp.5-33
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• 2019

This paper examines the problems of the concept of 'analogon' which occupies an important place in Jean-Paul Sartre's theory of imagination and his 'aesthetic of the unreal', focusing on Michel Dufrenne's objection to the concept. In the Imaginary (1940), Sartre offers a phenomenological account of the imaginative experience and his theory of imagination provides the basis for his account of experience of art. Sartre distinguishes the imagining consciousness from the realizing consciousness of perception. The work of art, for Sartre, is transformed into an irreal thing ("The work of art is irreality."), i.e. it appears only as aesthetic object, and only under the condition that the spectator's consciousness changes into an imagining consciousness. Some claim that Sartre underemphasizes the function of materiality in artworks. Mikel Dufrenne, in his The Phenomenology of Aesthetic Experience (1953), criticizes Sartre's thesis of irreality. Dufrenne argues that the aesthetic object is the work of art accomplished by aesthetic perception, the meaning of the aesthetic object is given as a whole in the sensuous and does not refer to something that lies outside the object as with imagination or irreality. An affective a priori is the condition of possibility for the occurrence of aesthetic experience.