• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.92-101
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• 2008

The purpose of this study was to investigate the dental caries prevalence and occlusion pattern of children with deciduous dentition in Chonnam seashore area. Two thousand two hundred seventy two kindergarten children ranged 3 to 5 years of age were examined. The obtained results were as follows : 1. The rate of children with caries experience(dmf rate) in deciduous teeth was 66.8% at 3 years of age, 77.7% at 4 years of age, and 83.5% at 5 years of age and showed no significant gender differences(p>0.05). 2. The mean number of decayed, missing, filled deciduous teeth(dmft index) was 3.62 at 3 years of age, 4.73 at 4 years of age, and 5.96 at 5 years of age and showed no significant gender differences(p>0.05). 3. Most of the caries-prevailed tooth was mandibular 2nd primary molar and showed 39.48% at 3 years of age, 49.73% at 4 years of age, and 63.85% at 5 years of age. 4. The caries-experienced teeth in order were as follows : mandibular 2nd primary molar with 52.34%, mandibular 1st primary molar with 45.61%, maxillary 2nd primary molar with 38.81%, and maxillary primary central incisor with 38.86%, respectively. 5. In sagittal primary molar relationship, Class 1 occlusion pattern was 53.26%, Class 2 pattern was 1.41% and Class 3 pattern was 30.02%, respectively. Right Class 2 and Left Class 3 pattern was not observed.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.678-685
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• 2006

A certain width of attached gingiva is required to maintain gingival health The purpose of this study was to examine the dimensional changes in the width of attached gingiva and the depth of gingival sulcus among the deciduous, mixed and permanent dentitions and establish baseline information on the width of attached gingiva in Korean children. Eighty-eight children aged 4 to 14, who visited the Department of Pediatric Dentistry at Samsung Medical Center, were selected and divided into 3 groups according to the periods of dentition: deciduous, mixed and permanent dentitions. The width of keratinized gingiva and the depth of gingival sulcus were measured in each group with a periodontal probe and the width of attached gingiva was determined. The width of attached gingiva in maxillary and mandibular first molars increased significantly with age after eruption in the permanent dentition (p<0.05). The sulcus depth significantly increased in newly erupted permanent teeth with narrower width of attached gingiva (p<0.05) in all of the experimented teeth with the exception of the mandibular central incisor during the transition period. The results suggest that the mean width of attached gingiva does not increase steadily from the deciduous to the permanent dentition.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.4
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• pp.314-321
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• 2014

This study investigated the pattern and treatment of traumatic dental injury (TDI), with respect to the time elapsed prior to the initial visit to the Department of Pediatric Dentistry, Chonnam National University Dental Hospital for TDI, from January 2009 to December 2013. The dental trauma records of a total of 378 patients (940 traumatic teeth) were analyzed. The prevalence rate of dental trauma was twofold higher in males versus females. The principal cause of injury, among all participants, was falling (36.5%). The most commonly affected teeth were the maxillary central incisors (66.9%). Subluxation (43.9%) represented the most common trauma for primary teeth, and uncomplicated crown fracture in permanent teeth (30.9%). Only 10% of patients visited the dental clinic within 1 hour of sustaining trauma. The principal treatment provided for primary teeth, during the initial clinical visit, was follow-up (53.2%); for permanent teeth it was root canal treatment (27.3%). The prevalence of root canal treatment for permanent teeth increased commensurate with the time elapsed since injury. These data suggest that delayed checkup following trauma may increase the risk of loss of pulp vitality.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.649-656
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• 2005

The present study was designed to formulate cephalometric norms of normal occlusion for usage in orthodontic diagnosis of malocclusion in Korean children. Thirty two children, aged 4 to 6, with normal occlusion were chosen for this study, Sagittal and vertical relations were analyzed using lateral cephalogram and clinical photos and the measurements were compared with those of adults. On skeletal sagittal analysis, the mean values of the SNA and SNB angles were $83^{\circ}\;and\;78.72^{\circ}$. It showed that the mandible was retrognathic and retropositioned in comparison to those of adults. On skeletal vertical analysis, the mean values of the genial angle was $127^{\circ}$. This showed high angle pattern in children and reduction of genial angle due to counterclockwise rotation of the mandible is expected with growth. On soft tissue analysis, children showed convex pronto, obtuse nasolabial angle. On dental analysis, the mean values of the U1 to SN and IMPA were $91.04^{\circ}\;and\;86.57^{\circ}$. This showed retroclined upper and lower deciduous teeth in comparison to adults. For skeletal values, the liner values were generally greater in males than females.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.328-337
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• 2010

The purpose of this study was to research the traumatized primary teeth and investigate following factors: sex, age, cause, place and time(of the year) of injury, elapsed time, area and type of injury, dental treatment and prognosis. The analysis includes total of 1533 traumatized primary teeth from 758 children aging from 6 months to 6 years(mean age: 2.8) from 2003 to 2007. The result follows : 1. The children of age between 1-2 and 2-3 were involved in the largest number of injuries in both sexes with boy/girl ratio of 1.77:1(p<0.001). 2. Fall and collision were the main causes of traumatic dental injury, especially in younger children(p<0.05). Places of injury occurrence varied: home, outdoors, and kindergarten. Warm climate accounts for frequent outdoor injuries in May, September and October(p<0.001). 3. Most of the children visited dental clinic within 24 hours of the injury(77.6%). From March to September, dental trauma occurrences were distributed evenly, except for Winter period(p<0.001). 4. Upper central incisors were the most commonly affected teeth, and the injuries usually involved 1 tooth or 2 teeth. 5. Periodontal tissue injuries dominated and subluxation was the most common type. Lateral luxation, enamel fracture, intrusion and root fracture followed.

• Journal of dental hygiene science
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• v.13 no.4
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• pp.426-433
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• 2013

The objective of this study was to examine whether there is an association of oral health conditions between mothers and their preschool children in Korea. A sample of 823 preschool children and their mothers were selected for this study from the database of the fourth Korean National Health and Nutrition examination Survey. Preschool children were defined as children aged 4, 5, and 6 years old. The subjects were clinically examined for the presence of caries lesions (dft index) and their mother was checked for the presence of dental caries (DMFT index) and periodontal status (CPI). The socio-demographic characteristics and mother's oral health behaviours were considered covariates in this study. Univariate and multivariate analysis was adapted to assess the association of oral health condition between mothers and their preschool children. In univariate analysis, there were significant differences between preschool children's dft index and their mother's age (p=0.005), dental treatment demand for the past one year (p=0.034), and DMFT index (p=0.016). In multivariate analysis, only mother's DMFT index was significantly associated with their children's dft index after adjusting for covariates. In conclusion, the mother's oral health was partly associated with their preschool children's oral health in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.1
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• pp.1-12
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• 2006

The purpose of this study were to evaluate the efficacy of the newly developed Digital Imaging Fiber-Optic Trans-illumination (DIFOTI) system in detecting carious lesions in vivo as gold standard with confocal laser scanning microscopy and compared the efficacy of traditional radiography and DIFOTI system in vito as gold standard with confocal laser scanning microscopy, too. For the in vivo study, the subject pool consisted of 23 grammar school age patients just prior to entering the mixed dentition phase Each patient was given a DIFOTI examination of the anterior and posterior teeth. During $6{\sim}8$ months, the naturally expire primary teeth were collected and the efficacy of DIFOTI system was compared with confocal laser scanning microscopy. For in vitro study, 40 primary teeth were collected and decalcified by Carbopol decalcification solution for 1, 2, 4 and 8 days. Every experiment period, all teeth were DIFOTI examined and sectioned to take an image of confocal laser scanning microscopy Sensitivity and specificity were calculated from the result of DIFOTI examine and confocal laser scanning microscopy analysis. The results are as follows : 1. From the in vivo study, the sensitivity of DIFOTI examine was 0. 61 and specificity was 0.63. 2. From the in vivo study, the sensitivity of DIFOTI examine was 0.71 and specificity was 0.75.

• Korean small business review
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• v.43 no.1
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• pp.165-186
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• 2021

Startups are undergoing a change throughout the growth process of startups that appear in existing studies as they move away from the existing B2B or B2C frame and expand their target customer groups to O2O, C2C. In this regard, a new type of startup known as unicorns, a unicorn which has grown rapidly in a short period of time, is being created by successfully attracting government support and external investment in recognition of the potential value of the startup. This study examined the relationship between investment attraction and growth after founding for five representative unicorns in the U.S. and Korea. As a result, it was found that private investment in Korea is passive and defensive, and is attracted after the Series A stage, compared to the U.S., where the growth potential of the startup ecosystem is positively evaluated. In addition, it found that government's support policy throughout the startup's growth process is an abstract and comprehensive policy focusing on initial funding for startups. Therefore, it was suggested that the scope of government policies should be expanded to forster startups as unicorns, and that it is necessary to establish and implement differentiated support policies for each growth of the scale-up of startups. This study is significant in that it presented the criteria for the growth stage and support of startups as well as policy support for scale-up through practical case analysis of unicorns.

• Journal of Popular Narrative
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• no.26
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• pp.413-433
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• 2011

What this study aims is to analyze that how the stories of Prince Hodong are represented in modern historical fictions. The stories have been reproduced in many forms such as TV dramas, films, fictions, plays. It can be depicted that the narratives are indeed national and popular. Interestingly, however, the description of Hodong has not been found in pre-modern documents or fictions. The story began to appear and became popular in 1935 by Yoon Baek Nam. It can be explained that the narratives are the one of the example of the invented tradition since it became visible in modern period. Yoon, Lee Tae Joon, and Yu Chi Jin have constructed the character of Hodong what we are familiar with. Yoon depicted Hodong as a romatic lover with the motif of a lovers suicide. Lee and Yu put a context of nationalism by explaining Nakrang as a Nakrangkun of Hansagun(the four colonies of China). These are pure invention of the writers which cannot be found in The History of Three Kingdoms(三國史記). These characters are closely related with the surrounding of their own society. Yoon shows how the past can be seen as a nostalgic object by modern aesthetic perspective. Lee illustrates the ambiguous thought of a colonial intellectual who (anti)internalizes the ideology of militarism. Yu tries to find the way to recover the muscularity of the nation by re-colouring the memory of the past. These, the representations created in various contexts, make our common knowledges of Prince Hodong nowadays.

• Journal of The Korean Association For Science Education
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• v.6 no.2
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• pp.63-72
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• 1986

과학교육은 학생들이 장차 과학 기술분야의 직업을 추구하도록 하는 것을 그 중요한 결실의 하나로 잡고 있다. 현재 한국은 과학과 기술의 발전을 교육의 주요목표의 하나로 삼고 있으며, 정부에서는 보다 많은 영재를 과학 기술분야로 유치하려고 여러 가지 정책을 펴고 있다. 그러나 이러한 정책도 결국은 학생이 과학 기술분야로 모여들지 않으면 그 효과가 없게 된다. 그런 점에서 학생들이 어떤 이유로 과학 기술분야를 선택하는지 혹은 기피하는지 그 원인을 아는 것을 중요한 과제라고 할 수 있다. 본 연구는 과학 및 기술분야의 직업을 갖게 되는데 결정적인 역할을 하는 고교생의 문 이과반 선택에 있어 그 진로결정에 영향을 주는 제 요인들을 규명하는데 목적을 두고있다. 연구대상은 대구시내외 남 녀 고교 1학년생 109명(문과 56명, 이과 53명)이었으며 조사방법은 설문지법을 사용하였다. 조사결과는 학생들의 문 이과반 선택에는 장래직업, 대학전공, 적성, 학과목에 대한 능력, 흥미 선호도, 가족 및 주위의 권유 등이 주요요인임을 보여주고 있다. 그중 문과를 지원한 학생들은 대체적으로 자신의 적성 이과과목에 대한 능력부족 인식, 내신 및 학력고사에서의 성적취득용이성 등 주로 자신의 내적 동기와 관련된 요인들을 들고 있는데 비해, 이과를 지원한 학생들은 밝은 직업전망, 가족 및 주위의 권유 등 외적인 동기도 큰 작용을 하고 있음을 보여 대조를 이루고 있다. 또 문과를 지원한 학생은 이과가 공부하기가 어렵고 성적을 올리기도 힘들어 이과를 기피한 경향을 보이는데 반해 이과 지원자는 문과를 기피하여 이과로 왔다는 응답은 별로 없는 점이 대조를 보였다. 본 논문은 이러한 결과가 던져주는 시사점과 과학교육의 개선책에 관한 제언을 제시하면서 결론을 맺고 있다.