• The korean journal of orthodontics
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• v.50 no.1
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• pp.52-62
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• 2020

This case report presents the orthodontic treatment of a 25-year-old patient with skeletal Class II and severe maxillary arch crowding, moderate mandibular arch crowding, anterior crossbite, and a missing lower incisor. He was treated with molar distalization using a modified C-palatal plate and temporary anchorage devices to create sufficient space for retraction. The total treatment duration was 21 months. After treatment, his occlusion and smile esthetics showed significant improvement. The modified C-palatal plate represents a treatment modality that enhances the prospects of non-extraction treatment and reduces the need for extraction.

• The korean journal of orthodontics
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• v.45 no.4
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• pp.190-197
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• 2015

Objective: The aim of the study was to analyze the prevalence and distribution of ectopic eruption of the permanent maxillary first molar (EEM) in individuals scheduled for orthodontic treatment and to investigate the association of EEM with dental characteristics, maxillary skeletal features, crowding, and other dental anomalies. Methods: A total of 1,317 individuals were included and randomly divided into two groups. The first 265 subjects were included as controls, while the remaining 1,052 subjects included the sample from which the final experimental EEM group was derived. The mesiodistal (M-D) crown width of the deciduous maxillary second molar and permanent maxillary first molar, maxillary arch length (A-PML), maxillomandibular transverse skeletal relationships (anterior and posterior transverse interarch discrepancies, ATID and PTID), maxillary and mandibular tooth crowding, and the presence of dental anomalies were recorded for each subject, and the statistical significance of differences in these parameters between the EEM and control groups was determined using independent sample t -tests. Chi-square tests were used to compare the prevalence of other dental anomalies between the two groups. Results: The prevalence of maxillary EEM was 2.5%. The M-D crown widths, ATID and PTID, and tooth crowding were significantly greater, while A-PML was significantly smaller, in the EEM group than in the control group. Only two subjects showed an association between EEM and maxillary lateral incisor anomalies, which included agenesis in one and microdontia in the other. Conclusions: EEM may be a risk factor for maxillary arch constriction and severe tooth crowding.

• The korean journal of orthodontics
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• v.25 no.5 s.52
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• pp.593-604
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• 1995

Mandibular incisor crowding is one of the most common features of malocclusion and is interesting characteristic in view of relapse and stability after orthodontic treatment. There are many potential factors in the etiology of lower anterior crowding. The tooth size variation is one of them, but biologic significance for the faciolingual width of the teeth has been overlooked. Peck and Peck reported that persons with ideal mandibular incisor alignment were shown to have incisor with smaller mesiodistal and larger faciolingual dimensions than persons with incisor crowding. On the basis of these findings they suggested MD/FL index as a clinical guideline for the assessment for lower incisor crowding. The present study was undertaken to examine the relationship between mandibular incisor crowding and mandibular incisor dimension, and determine their correlation with arch length discrepancy. 154 dental casts of people from 11 to 17 years of age were made, and were divided into normal group with irregularity index less than of 1, and crowding group with irregularity index greater than 1.The casts were measured and analyzed statistically. The results were as follows. 1. The mean mesiodistal width for mandibular incisor was larger in crowding group, and has significant difference in central inciosr measurement. There are no significant differences in the faciolingul width and MD/FL index. 2. Irregularity index has significant correlation coefficients with mesiodistal width and MD/FL index for mandibular incisor in crowding group, but no correlation with faciolingual width. It also has correlation with maxillary and mandibular arch length discrepancy, total tooth material, mandibular intercanine width, and mandibular inter first premolar width. 3. Upper and lower arch length discrepancy have significant correlation with mesiodistal width of mandibular incisor and overbite, but have no correlation with faciolingual width. Lower arch lenth discrepancy has significant correlation with MD/FL index for mandibular incisor and upper arch length discrepancy has correlation with MD/FL index for mandibular lateral incisor. 4. Significant differences were observed between normal and crowding group for the mandibular arch length discrepancy and overbite.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.3
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• pp.93-102
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• 1992

This study was carried out to estimate the recreation carrying capacity of lawn areas in parks. Recreation carrying capacity in this study is composed of two parts, ecological carrying capacity. This part deals with the psychological carrying capacity, based on the perception of crowding level and recreation satisfaction of users. The survey was conducted at the lawn areas of Doturag World and Seorabul Plaza in Bomun Resort Complex in Kyungju. The major results are as follows: 1. As the result of regression of regression analysis between use density of lawn area and level of perceived crowding, the capacity was estimated as 60.0㎡ man. 2. As the result of regression analysis between use density of lawn areas and total recreation satisfaction, the capacity was estimated as 48.5㎡/man. 3. As the result of regression analysis between use density of lawn areas and satisfaction to use density, the capacity was estimated as 63.2㎡/man. 4. As a conclusion, the psychological carrying capacity was estimated as 60.0㎡/man. And this value is based on user's perception of crowding and recreation satisfaction level for each use densities.

• The korean journal of orthodontics
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• v.47 no.2
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• pp.130-141
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• 2017

The aim of this case report was to describe an innovative orthodontic treatment method that combined surgical and orthodontic techniques. The novel method was used to achieve a positive result in a case of moderate crowding by employing a computer-guided piezocision procedure followed by the use of clear aligners. A 23-year-old woman had a malocclusion with moderate crowding. Her periodontal indices, oral health-related quality of life (OHRQoL), and treatment time were evaluated. The treatment included interproximal corticotomy cuts extending through the entire thickness of the cortical layer, without a full-thickness flap reflection. This was achieved with a three-dimensionally printed surgical guide using computer-aided design and computer-aided manufacturing. Orthodontic force was applied to the teeth immediately after surgery by using clear appliances for better control of tooth movement. The total treatment time was 8 months. The periodontal indices improved after crowding correction, but the oral health impact profile showed a slight deterioration of OHRQoL during the 3 days following surgery. At the 2-year retention follow-up, the stability of treatment was excellent. The reduction in surgical time and patient discomfort, increased periodontal safety and patient acceptability, and accurate control of orthodontic movement without the risk of losing anchorage may encourage the use of this combined technique in appropriate cases.

• Journal of the Korea Society of Computer and Information
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• v.20 no.5
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• pp.141-150
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• 2015

The object of this study is finding out the relational effect of perceived crowding of international airport on emotional response and revisit intention. The data of this study was collected by questionnaire and based on Incheon international airport visitors. A total 260 validity sample was analyzed a frequency analysis, reliability analysis, exploratory factor analysis and correlation coefficient analysis from SPSS 21, a hypothesis through out confirmatory factor analysis and structural equation modeling from AMOS 7.0. As a result of this study, visitors' human perceived crowding of international airport and positive emotional response showed a significant effects on revisit intention.

• The korean journal of orthodontics
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• v.43 no.3
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• pp.147-158
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• 2013

This article describes the orthodontic treatment of a 31-year-old Korean female patient with gummy smile and crowding. The patient showed excessive gingival display in both the anterior and posterior areas and a large difference in gingival heights between the anterior and posterior teeth in the maxilla. To correct the gummy smile, we elected to intrude the entire maxillary dentition instead of focusing only on the maxillary anterior teeth. Alignment and leveling were performed, and a midpalatal absolute anchorage system as well as a modified lingual arch was designed to achieve posterosuperior movement of the entire upper dentition. The active treatment period was 18 months. The gummy smile and crowding were corrected, and the results were stable at 21 months post-treatment.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.243-247
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• 1986

174 patients who visited in the Department of Dentistry, College of Medicine, Yeungnam University from 1983. 7. 15 to 1986. 11. 30 were surveyed on the tendency of patient distribution and the state of Angle's classification. The results were as follows : 1. There was increased visiting rate of patient per year. Female outnumbered male by a ratio of 1.3 : 1. 2. 8-15 age group was 74% in total visiting in the most frequency. The average visiting numbers of each month were higher among the vacation and was about 74% in that period. 3. As showed the living distribution, Nam Gu and Su Sung Gu's patients were 53% of the total. 4. As the motive of visiting in Dental Department, patients of 30% in total patients visited for themself to receive orthodontic treatment and others was introduced patients. 5. By classification, Class I malocclusion was 63% in total visiting patient, Class II malocclusion 17%, ClassIII malocclusion 20%. Crowding among Class I malocclusion was 60%.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.5
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• pp.1-18
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• 2019

A short-turn bus is a bus that is operated within a subsection of an existing bus line. Previous studies regarding short-turn buses decided optimal turn-back points for a single bus line rather than a bus network. Also, in-vehicle crowding which has a significant impact on transit convenience was rarely considered. Therefore, this study aimed to develop a methodology to set priorities for the introduction of short-turn buses of bus lines and sections, considering crowding. To achieve this objective, we calculated occupancies and crowding alleviation benefits of existing bus lines overlapping a new short-turn route based on transit card data, before and after the introduction of short-turn strategy. Also, operator and social costs caused by the introduction of short-turn buses were calculated. Those procedures were iterated over bus lines and sections to operate a short-turn service, and a section whose benefit-to-cost ratio (B/C) is the largest in a line was selected to operate a short-turn service in the line. After, priorities of bus lines to introduce short-turn services could be determined based on B/C values, and the optimum total fleet size could be determined when a short-turn strategy is applied in multiple lines.

• Journal of Technologic Dentistry
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• v.35 no.1
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• pp.67-76
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• 2013

Purpose: The purpose of this study is to compare and analyze the difference in chewing ability according to the malocclusion and orthodontic treatment for the university students who are adults and consider the effect of the malocclusion and orthodontic treatment on chewing ability. Methods: This study conducted the survey for 400 students of the two universities located in Daegu, Gyeongsangbuk-do, and except for the poor or erroneous surveys among 400 survey copies of the participants, total 363(90.75%) survey copies were used for the study analysis. Results: The total result of chewing ability for the food showed that middle-class students had higher chewing ability than high-class students and the students who didn't get orthodontic treatment had higher chewing ability than the students who are getting orthodontic treatment now. In the chewing ability for various kinds foods, in case of young radish kimchi, the result showed that the students who have a little crowding or normal level of teeth or normal teeth has higher chewing ability than the students who have severe crowding level of teeth, and in case of the foods including kkakdugi or galbi, the result showed that the students who have normal teeth location or the 3rd level malocclusion have higher chewing ability statistically significantly than the students who have the 2nd malocclusion. Conclusion: For the chewing ability, the middle-class students in the home economic power showed significantly higher chewing ability than the high-class students in the home economic power, and the students who didn't get any orthodontic treatment showed higher chewing ability statistically significantly than the students who are getting orthodontic treatment now.