• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.169-179
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• 1984

The purpose of this study was to observe the effect of dental varnish applied with fluoride to dental pulp by comparing the groups of commercial fluoride product $Duraphat^{(R)}$, $Copalite^{(R)}$ after 1 Mole sodium fluoride application, Cavity $Sealer^{(R)}$ after 1 Mole sodium fluoride application with the control group not applied the dental varnish. After Cl V Cavity form was prepared on the buccal surface of the crowns with the total 75 teeth by using 5 dogs, average weight of 13.2Kg, dental varnish and silver analgram were placed. This study was performed by 3, 7, 21, 28, 56 days each. The dogs were sacrificed to extract the teeth, cut at the apical one fourth, and prepared histologic examination by fixing with 10% buffered formalin perfusion at sacrifice and decalcification in 10% nitric acid. The specimens were embedded in paraffin, stained with Hematoxylin and Eosin, and serially sectioned with 6 ${\mu}$width each. Microscopic evaluation of serial sections at the various time periods among the different groups revealed the following results: 1. In the control group, the marked change of the odontoblastic layer was showed on the 3 days group, and it was decreased gradually. Healing response, such as hyperplasia, was seen on the 28 days group and it was continued to the 56 days group. 2. In the experimental group with Cavity $Sealer,^{(R)}$ a slight hemorrhage was seen in the odontoblastic layer on the 3 days group, and the healing response with the hyperplasia of the odontoblast was showed on the 21, 28 days group. It was completely healed on the 56 days group. 3. In the Duraphat R group, a slight hemorrhage showed on the 3 days group and the disarrangement of the Odontoblastic layer was seen on the 7, 21, 28 days group. Odontoblasts showed hyperplasia on the 28 days group, and healed completely on the 56 days group. 4. In the $Copalite^{(R)}$ group, the 7 days group showed remarkable hemorrhage in the odontoblastic layer and stroma, and also it showed reticular degeneration with the disarrangement of the odontoblastic layer and congestion. Each group showed disarrangement. Healing ability of this group was greater than that of the control group, but less than that of the $Duraphat^{(R)}$ and Cavity $Sealer^{(R)}$ group.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2497-2504
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• 2013

This study aims to analyze the 'Standard Drawings for School Facilities' issued by Seoul Education Committee in 1975 because it is the early example for middle school architecture. The results of this study are summarized as follows 1) In general trend of single-corridor type block plan, there are also changes in floor plan like no-corridor type block plan, $9.9{\times}6.6m$ classroom unit for the better daylight condition, built-in storage for students. 2) As for elevation design, it is characterized as daylight-oriented, functional exterior for without making full use of design elements. 3) Standardized dimensions are used as a rule in the height of story, ceiling, window sill and etc. Transitional characteristics of the early RC school architecture are found in exposed ceiling, incomplete insulation structure and mixed use of wood framed floor of earlier type. 4) Contrast to main school building, gymnasium shows the intend to express the symbolism of school architecture with diverse elevation design elements and the plasticity of building mass. 5) Separated plan of toilet and night-duty building also show the transitional characteristics. As conclusion, though showing the stereotyped school architecture, on the other hand, 'Standard Drawings for School Facilities' (1975) makes it possible to see the way of coping with the demands for school architecture in that time and the transition of school architecture. This is the main value of it as the material for the studies related to the history of educational facilities.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.619-626
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• 2020

This study aimed to identify the error rates in Catheter Calibration Mode, Auto Calibration Mode, and Segment Calibration Mode among many calibration modes as a quantitative evaluation tool used for predicting the diameter and length of balloon or stent in percutaneous intravascular balloon dilatation or stent insertion. Our experiment was conducted with Copper Wire of 2 mm × 80 mm (diameter × length) manufactured elaborately for quantitative evaluation in calibration and Metal Ball of 5, 10, 15, 30, and 40 mm and Acryl Phantom of 25 mm, 50 mm, 75mm, 100 mm, 125 mm, 150mm, 175 mm, and 200 mm. At each height, subtraction images were acquired with a cineangiograph and Stenosis Analysis Tool as a software provided by the equipment company was used for measurement. To evaluate the error rates in Catheter Calibration Mode, Copper Wire was put on each acryl phantom before shooting. Copper Wire of 2 mm in diameter was set as a diameter for catheter, and Copper Wire of 8 mm in length was measured with Multi-segments. As a result, the error rates appeared at 1.13 ~ 5.63%. To evaluate the error rates in Auto Calibration Mode, the height of acryl was entered at each height of acryl phantom and the length of 8 mm Copper Wire was measured with Multi-segments and as a result, the error rates appeared at 0 ~ 0.26%. To evaluate the error rates in Segment Calibration Mode, each metal ball on the floor of table was calibrated and the length of 8 mm Copper Wire on each acryl phantom was measured and the length of 8 mm Copper Wire depending on the changes of acryl phantom height was measured with Mutli-segments and as a result, the error rates appeared at 1.05 ~ 19.04%. And in the experiment on OID changes in Auto Calibration Mode, the height of acryl phantom was fixed at 100mm and OID only changed within the range of 450 mm ~ 600 mm and as a result, the error rates appeared at 0.13 ~ 0.38%. In conclusion, it was found that entering the height values in Auto Calibration Mode, among these Calibration Modes for evaluating quantitative vascular dimensions provided by the software was the calibration method with the least error rates and it is thus considered that for calibration using a metal ball or other objects, putting them in the same height as that of treatment sites before calibrating is the method that can reduce the error rates the most.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.455-467
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• 1996

This study was designed to evaluate the expression of type I collagen in periodontal tissue during the experimental movement of rat incisors. Twenty-one Sprague-Dawley rats were divided into a control group(3 rats), and experimental groups(18 rats) where a force(75g) from helical springs across the maxillary incisors was applied. Experimental groups were sacrificed at 12 hours, 1, 4, 7, 14 and 28 days after force application, respectively. And tissue slides of control and experimental groups were studied histologically and immunohistochemically by LSAB(Labelled streptavidine Biotin) immunohistochemical staining for type I collagen. The results were as follows: 1. Until 28-day after force application, periodontal fibers were strectched on the tension side, and compressed in pressure side, and the arrangement of periodontal fibers was not recovered by that time. 2. The degree of type I collagen expression in control group was rare in the oral epithelium, predentin, pulp and periodontal ligament, but was mildly positive in osteoblasts, acellular cementum, cementoblasts, intermaxillary suture. 3. At acellular cementum of experimental group, the expression of type I collagen was moderate in 1-day and severe in 7-day, which was maintained until 28-day. 4. Type I collagen was observed in the newly formed fibrous connective tissue and osteoblasts at intermaxillary suture, moderately in 1-day, and severely in 14-day. 5. The tension side of periodontal ligament showed a more positive expression of type I collagen than the pressure side in 4-day. The degree was highest in 7-day and was not differentiated between sides in 14-day. 6. In the side wall of bone matrix on which osteoblasts were attached, type I collagen was expressed severely, especially in 7-day. From the above findings, we could suggest that bone remodeling in tooth movement be intimately related to the cell differentiation and the resulting formation of type I collagen.

• The korean journal of orthodontics
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• v.25 no.4
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• pp.433-445
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• 1995

Tooth movement, the phenomena and mechanisms of which are still controversial, can be considered as part of the result of the inflammatory processes. The purpose of this study was to examine the activity of macrophage and T-cell, playing important roles in the immune reaction, in the periodontal ligament of dog, in which experimental tooth movement was performed. Six one and half year-old dogs, a control and 5 experimentals, were studied. Light force (50-75g) was applied by placing open-coil spring between left mandibular premolars ; heavy force (250-300g), between right mandibular premolars. Experimental dogs were sacrificed at 12 hours, 1, 3, 7 and 14 days since force application, respectively. And the histologic and the immunohistochemical evaluation on the obtained tissue were performed, using $\alpha$-1-antichymotrypsin and CD3 antibodies. The results were as follows : 1. There were more inflammatory cell infiltrations in heavy force group than in light force group until 3 days. But from 7 dsays on, no difference was not observed between groups ; Such an infiltration was more evident at pressure side than at tension side. 2. Osteoclastic activity at pressure side began to be seen in 12 hours, increasing until 7 days. After then it decreased ; Such an activity was more evident in heavy force group than in light force group. 3. Tearing of periodontal ligament and vascular dilatation at tension side began to be seen in 12 hours, increasing until 3 days. After then it decreased ; Such an observation was more evident in heavy force group than in light force group, but there was no difference between groups in 14 days. 4. $\alpha$-1-antichymotrypsin expression in control group was positive, mainly in sulcular epithelium, but negative in periodontal membrane, pulp, bone cells. 5. $\alpha$-1-antichymotrypsin expression in experimental group was more positive in pressure side than in tension side ; The expression was a little more positive in cervical area of tooth until 3 days, but after 7days, it was more positive in apical area. 6. $\alpha$-1-antichymotrypsin expression in light force group began to be observed in 12 hours and reached to the greatest level in 7 days, after which it decreased ; In heavy force group, it was the greatest in 3 days, after which it decreased. 3 Expression in the periodontium was almost negative.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.249-259
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• 2001

This study was designed to evaluate the expression of heat shock protein in tooth and surrounding tissue during the experimental movement of rat incisors, by LSAB(labelled streptavidine biotin) immunohistochemical staining for heat shock protein. Twenty seven Sprague-Dawley rats were divided into a control group(3 rats), and 6 experimental groups(24 rats), to which 75g of force was applied from helical springs across the maxillary incisors. Rats of experimental groups were sacrificed at 0.5, 1, 4, 7, 14 and 28 days after force application, respectively. And the periodontal tissues of a control group and experimental groups were studied immunohistochemically. The results were as follows : 1. In control group, the expression of HSP47 was rare in gingiva, dentin and cementum, and mild in periodontal ligament and alveolar bone. But it was more evident than that of HSP70. 2. The expression of HSP47 or HSP70 was rare or mild in dentin, cementum and odontoblast of experimental group, regardless of the duration of force application, which was not different from that of control group. 3. In experimental group, the expression of HSP47 got to the highest degree in periodontal ligament and alveolar bone at 4 days after force application, and then decreased. And the expression was more evident in the pressure side than in the tension side of periodontal ligament 4. The expression of HSP70 began to increase at 12 hours after force application and got to the highest degree at 4 days, in the capillary of pulp and periodontal ligament. And the expression was more evident in the pressure side than in the tension side of periodontal ligament 5. The expression of HSP70 in alveolar bone of experimental group was rare, which was similar to that of control group.

• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.107-120
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• 2001

Nitric oxide(NO) has been reported to be one of the mediators relating to bone remodelling. Nitric oxide is synthesized from L-arguinine by nitric oxide synthetase(NOS), which is largely divided Into two groups. One group which is composed of $NOS_1\;and\;NOS_3$, is dependent of calcium or calmodulin. The other consisted of $NOS_2$, which is independent of calcium or calmodulin. NOS is thought to be a possible intermediate affecting in the course of tooth movement. This study was designed to evaluate the expression of nitrous oxide synthetase(NOS) in periodontal tissue during the experimental movement of rat incisors, by LSAB(labelled streptavidine biotin) immunohistochemical staining for $NOS_2\;and\;NOS_3$. Twenty seven Sprague-Dawley rats were divided into a control group(3 rats), and 6 experimental groups(24 rats), to which 75g of force was applied, with helical springs across the maxillary incisors. Rats of experimental groups were sacrificed at 12 hours, 1, 4, 7, 14 and 28 days after force application, respectively. After that, the tissues of the control group and experimental groups were studied immunohistochemically. The results were as follows: 1. In control group, the expression of $NOS_3$ was rare in gingiva, dentin, periodontal ligament and alveolar bone, and was mild in the capillaries of pulp and intermaxillary suture. And the expression of $NOS_2$ showed similar pattern to that of $NOS_3$. 2. There were no differences in the expression of $NOS_2\;or\;NOS_3$ in dentin, gingiva, cementum, cementoblast and odontoblast, between control and experimental groups, regardless of the duration of the force application. 3. The expression of $NOS_3$ began to increase at 4 days and showed to the highest degree at 7 days after force application, in the apical region of pressure side of periodontal ligament in experimental groups. 4. The expression of $NOS_3$ in alveolar bone was rare until 7 days, after which it increased to mild degree at 14 days through 28 days in experimental group. But there was no difference between pressure and tension side of periodontal ligament. 5. The expression of $NOS_2$ in periodontal ligament was mild from 7 days after force application, regardless of the side of periodontium, which was generally more evident than that of $NOS_3$. 6. The expression of $NOS_2$ in alveolar bone increased to mild degree at 14 days after force application, and it was evident in osteoblasts, osteoclasts and osteocytes. And the expression of $NOS_2$ was little more stronger in the tension side than that of pressure side of alveolar bone.

• Journal of dental hygiene science
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• v.4 no.1
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• pp.21-25
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• 2004

In modern times, children's trauma is increasing every year because of car accidents and life environment changes. There is a limit to prevent traumatic damage for oral cavity organization. The fundamental data of trauma treatment and prevention will be presented through the survey and analysis of traumatic teeth damage. I examined 113 patients from Oct. 4th, 2000 to Feb. 27th, 2004 at Dept. of Children's Dental Clinic, Kangnung National University. The results are as follows. (1) The trauma frequency of male subjects is higher than that of female at a rate of 2.05:1. The average age is 5.27 for men and 5.27 for women. The highest percentage of trauma patients is among 2 year old children. It is 21.2%. (2) A patient survey was taken at a trauma treatment hospital. On the first day 34.4% of the patients had come to receive treatment of their first set of teeth. However, after a week, 38.8% of the patients had received treatment on their permanent teeth. (3) As a result of falling, 59% of patients needing treatment on their first set of teeth. 55.1% of patients is permanent teeth. As a result of bump against physical solid, 26.6% of patients is the first set of teeth and 26.5% of patients is permanent teeth. (4) Teeth damage happened at home. 42.1% were male. 35.1% were female. According to trauma, 59.4% of teeth damage happened at home. 28.6% of permanent teeth damage happened at school or kindergarten. (5) According to trauma, the number of teeth damaged was in the first set of teeth are as follows: 56.3%, one-31.3%, three or four-6.3% each. For permanent teeth: two-46.9%, one-28.6%, four over-16.3% and three-8.2%. Over four teeth is larger number for permanent teeth. (6) 56% of first set of teeth patients and 43.4% of permanent teeth patients were male. 56.8% of first set of teeth patients and 43.2% of permanent teeth were female. Trauma happened to both male and female frequently in the first set of teeth. (7) Most of the tooth damage which was in the first set of teeth and permanent teeth was done to the upper jaw. 75% of patients are the first set of teeth. 63.8% of patients are permanent teeth. Trauma is very high in the two mid teeth of the upper jaw. (8) According to trauma survey, 30.2% is from impulse. 28.0% is from crown fracture, 14.7% is from depression. 8.9% is from concussion. 7.1% is from full dislocation of a joint. 2.2% of patients are extrusion. 1.8% is from displacement. According to teeth damage trauma, 35.8% is pulse in the first set of teeth. The breaking of the crown of a tooth happened a lot in permanent teeth. (9) According to data, 43.2% of teeth damage in the first set of teeth goes without treatment. In permanent teeth, it is 38.9%. After treatment, 22.0% of first set of teeth treatment requires a dental pulp treatment. In permanent teeth, which is used for temporary acid etching resin restoration.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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• pp.75-84
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• 2018

The inclusive playground is a playground where disabled children and non-disabled children can play together, not a playground for the disabled. It started with the change of social awareness of the citizenship rights of disabled people in the 1960s and the resulting playgrounds. Since then, inclusive playgrounds have been developed in many countries, and these are organized in the form by guidelines. In Korea, social interest in inclusive playgrounds is increasing, but there are no systematic guidelines in Korea, and the application of overseas cases or guidelines is limited. The purpose of this study is to classify the concept of inclusive playgrounds and design guidelines, that were previously presented in inclusive playground design guideline of various countries and analyze the characteristics of, design scope, and design principles, and provide a basic framework for creating guidelines. The purpose of the design guideline was to present specific numerical values to the inclusive playground design guidelines, to link with academic research and industrial products, to present pursuit values, and to expand the value of pursuing design methods. The contents were covered by scope, conceptualization, principles of design and design process, design guidelines, and checklists. Most of the guideline covers specific autonomous governments or countries that can apply the related systems or laws, but the composition of the detailed contents is different. The guiding value of inclusive playgrounds presented in each guideline is not a playground for the disabled but a playground for all, and some guidelines refer to the difficulty in playgrounds considering non-disabled children. Based on these concepts, design guidelines are presented in each guideline. Improving the accessibility in design principles is a common theme and adds to the principles of safety, independence, convenience, and playability. None of the guidelines do not provide design guidelines. Although there is a difference in the degree and method of specificity provided by each of the guidelines, the design guidelines can be generally summarized as space, copper line, and unit facilities. As mentioned in many guidelines, an inclusive playground is not only a playground for children with disabilities. Therefore, in the design guidelines, it is also important to the support play of children with disabilities and to induce inclusive play. The design guidelines presented in the guideline can be rearranged into three stages of 'supporting the play of children with disabilities', 'securing the dimensions and materials of spaces and facilities', 'adding auxiliary devices' and 'designing new facilities'. There are three design guidelines for inducing inclusive play. First, by creating various difficulty levels and intersecting spaces, children with various abilities can play with each other, and at the same time, they can interact witheach other. Second, all children can cooperate and play without distinction between children with disabilities and non-disabled children. Finally, the guardian provides the conditions for efficient support so that the disabled child can fully enjoy the inclusive playground.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.642-651
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• 2008

This study was carried out to give basic information of traumatic injuries of primary and permanent teeth which can be used for diagnosis and management of injured teeth. From January 2003 to July 2007, 570 children with 1394 teeth who came to pediatric dentistry and emergency center of Chonnam National University Hospital due to the traumatized teeth participated in this study. The following data were investigated. : age, sex, causes and places of trauma, position of injured teeth, types of injury, and treatment at the first visit. 1. Trauma prevailed at the age of 1, $6{\sim}8$, $17{\sim}18$ and the rate of males was more likely to be higher than the rate of females(1.9 : 1). 2. The main cause of injury is a fall-down injury for primary and mixed dentition, but is a traffic accident and fighting for permanent dentition, respectably. The place of injury for primary dentition is mainly home(45.3%), while street for mixed and permanent dentition. 3. The position of injured teeth according to the area in the mouth is mainly maxillary anterior teeth in both case of primary and permanent teeth and especially, the ratio of central incisors is high. 4. The periodontal tissue injury occurred the most frequently in the primary and the permanent teeth, but the ratio of hard tissue injury in the permanent teeth increased, compared with the primary teeth. 5. Among treatments at the first visit, observation without actual treatment comprised 75.6% in the primary teeth and 55.4% in the permanent teeth, respectably. The pulp necrosis occurred in 20.3% of the primary teeth and 26.6% of the permanent teeth in the case of the periodontal tissue injuries, respectably.