• Title/Summary/Keyword: Anterior plate

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A PHOTOELASTIC STUDY ON THE INITIAL STRESS DISTRIBUTION OF THE UPPER ANTERIOR TEETH WHEN INTRUSIVE FORCE APPLIED (BY UTILITY ARCHWIRE, BURSTONE INTRUSION ARCHWIRE, and 'J' HOOK HEADGEAR) (상악 전치부 INTRUSION시 초기 응력 분포에 관한 광탄성학적 분석(Utility archwire Burstone intrusion archwire, 'J'hook headgear에 의한))

  • Baik, Hye-Jong;Baik, Hyoung-Seon
    • The korean journal of orthodontics
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    • v.27 no.3 s.62
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    • pp.401-409
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    • 1997
  • The purpose of this study was to analize the initial stress distribution around apex and the alveolar bone of the upper anterior teeth when applying intrusive force by the use of utility arthwire, Burstono 3-piece infusion archwire, and 'J' hook headgear which is usually used in clinital practice. By the use of the polarization plate, initial stresses were analized when 80g and 150g forte applied. The results were as follows. 1. With the utility archwire, moderate levels of stress were evenly distributed on the apical areas of the anterior teeth and concentrated on the apical areas of the first molars. 2. With the Burstone's 3-piece intrusion archwire, moderate levels of stress were evenly distributed on the apical areas of the anterior and posterior teeth. 3. With the 'J' hook headgear, severe levels oi stress were widely distributed on the alveolar bone and apical areas of the upper anterior teeth, and concentrated on the apical area between the central and the lateral incisors. Especially, weak levels of stress appeared along the periodontal ligament space of all teeth.

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CONDYLAR ADAPTATION UNDER LATERAL DEVIATION OF THE RABBIT MANDIBLE (가토의 하악골 측방 변위에 의한 하악과두 변화)

  • Park, Hae-Sung;Park, Young-Ju;Ahn, Byoung-Keun;Rhee, Gun-Joo;Park, Jun-Woo;Lee, Young-Chan;Cho, Byoung-Ouck
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.5
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    • pp.446-454
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    • 2000
  • Condylar process of mandible is an important and fuctionally versatile part of the mandible. There were quite large amount of investigations on the functional and anatomical adaptation of the temporomandibular joint(TMJ) to the surrounding tissues. But controversies on the mechanism of functional adaptation of the joint still exist. In this research, we investigated changes in the TMJ by the lateral deviation of the maxillary incisor to shift the mandible right, and bone the undecalcified microscopic sections with fluorescent microscope and von Kossa staining with bright field microscope. Results were as follows: 1. Lateral deviation rendered shifting and tilting of the mandible, There were, compressions in the right joint and opening of the left joint space at early stage. At the same time, both condyles shifted slightly to anterior. 2. After $2{\sim}4$ weeks, left condyle showed anterior displacement and compressions in the joint space. Right condyle showed only slight shift to the anterior. 3. Regardless of the direction of the lateral shift, anterior bite plate compressed both condyle heads until 2 weeks. 4. There are bone resorptions in the anterior aspect of the condyle head and apposition of posterior border. Bone remodeling were observed between 3 and 4 weeks. 5. After 8 weeks of the experiment, there were little differences in condylar morphology between experimental and control group, though slight shifting and compression were still present in the experimental group. Lateral deviation of mandible evoked active remodeling of the TMJ until functional and anatomical reconstruction of TMJ position was achieved.

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A New Record of Notodontidae Moth, Neodrymonia marginalis in Korea

  • Choi, Sei-Woong;Kim, Sung-Soo;Jeon, Ju-A
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.2
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    • pp.164-166
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    • 2020
  • Herein, we report a new record of Notodontidae moth, Neodrymonia marginalis (Matsumura) in Korea. This species is characterized by grayish forewing that shows thick dark grayish band between basal and antemedial line, smooth postmedial line costally with blackish crescent line, dark grayish subtermen with dark brownish thick band costally, and whitish and black dot shaped discal dot. The female genitalia can be distinguished by the broad, plate-shaped postvaginalis, strongly sclerotized ductus dursae with three long spike shaped and several small spike shaped processes, and large, ovate corpus bursae with a large fan-shaped plate signum. Neodrymonia marginalis can be distinguished from N. deliana by the shape and color of the costal part of postmedial line and subtermen of forewing. The female genitalia of N. marginalis can be distinguished from those of N. deliana by the rectangular postvaginalis and more spike like processes of the anterior of ductus bursae. Up to now, four species of Neodrymonia are recorded in Korea: N. delia (Leech, 1889), N. coreana Matsumura, 1922, N. deliana Gaede, 1933, and Neodrymonia marginalis.

EFFECT OF IMMEDIATE DRAINAGE ON THE SURGICAL EXTRACTION OF IMPACTED MESIODENS IN CHILDREN: REPORT OF CASES (어린이에서 상악 정중부 매복 과잉치 발치 시 즉시 배액술의 효과: 증례보고)

  • Lee, Chun-Ui;Yoo, Jae-Ha;Choi, Byung-Ho;Sul, Sung-Han;Kim, Ha-Rang;Mo, Dong-Yub
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.32 no.3
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    • pp.256-259
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    • 2010
  • Impacted supernumerary anterior teeth (mesiodens) usually are removed surgically with drug sedation and local anesthesia. After extraction of mesiodens, the wound are sutured and removable resin plate is then applied. In this operation, the postoperative bleeding and infection is likely to occur owing to postoperative accumulation of hematoma & seroma, psychologic stress and other contaminated factors (resin plate, poor oral hygiene, etc). So, the authors established the immediate rubber & iodoform gauze drainage into the sutured wound of mesiodens extraction for the prevention of postoperative bleeding and infection. The removable resin splint are not used because of the poor oral hygiene and economic factor. The results were more favorable without the postoperative blood oozing & wound infection in the dentistry (OMFS) of Wonju Christian Hospital.

A Biomechanical Analysis of Foot-Floor Reaction Forces Measured When Walking over an Obstacle (장애물을 걸어서 넘어갈때 측정한 발반력에 대한 생체역학적 해석)

  • Yun, Jong-Il;Son, Kwon;Lee, Min-Cheol
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.7 s.94
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    • pp.1864-1873
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    • 1993
  • A biomechanical approach was carried out to analyze foot-floor reaction forces acting on five male subjects performing a walking task. The task analyzed was walking over an obstacle with the right bare foot. The foot-floor reaction data were measured from a force plate, and then processed using a software developed. The source program was coded in the C language for easier on-line data acquisition and graphic displays. High repeatability was found in the reaction data acquired from three trials by each subject. For obstacle height from 0 to 25 cm, the maximum in reaction force reached up to 1.048 BW in the vertical, 0.174 BW in the anterior-posterior, and 0.054 BW in the medio-lateral components, respectively. A quantity was defined by the difference between two vertical reaction values, and this quantity was found to be proportional to the obstacle height. It was also shown that the whole body motion could be predicted the measured foot-floor reaction data.

Characteristics of Dynamic Postural Control in Anteroposterior Perturbation of a Platform (전후방향의 플랫폼 이동에 대한 동적균형 회복 특성)

  • 태기식;김영호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1066-1069
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    • 2002
  • Dynamic postural control varies with the environmental context, specific task and intentions of the subject. In this paper, dynamic postural control against forward-backward perturbations of a platform was estimated using tri-axial accelerometers and a force plate. Ten young healthy volunteers stood upright in comfortable condition on the perturbation system which was controlled by an AC servo motor. With anterior-posterior perturbations, movements of ankle, knee and hip Joints were obtained by tri-axial accelerometers. and ground reaction forces with corresponding displacements of the center of pressure(CoP) by the force plate. The result showed that the ankle moved first and the trunk forward, which implies that the mechanism of the dynamic postural control in forward-backward perturbations, occurred in the procedure of the ankle, the knee and the hip. Knee flexion and hip extension in the period of acceleration, constant velocity and deceleration phase is very important fur the balance recovery. These responses depends on the magnitude and timing of the perturbation. From the present study the accelerometry-system appears to be a promising tool for understanding kinematic accelerative In response to a transient platform perturbation. A more through understanding of balance recovery mechanism may aid in designing methods for reducing falls and the resulting injuries.

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Unrecorded subgenus of black fly (Diptera: Simuliidae) from Korea

  • Kim, Sam-Kyu
    • Journal of Species Research
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    • v.9 no.1
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    • pp.19-25
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    • 2020
  • Larvae, pupae, and adults reared from the pupae of Simulium (Boreosimulium) konoi were collected and recorded from Korea for the first time. I provide detailed descriptions of both immatures and adults accompanied with photographs. The subgenus Boreosimulium, previously unknown from Korea, contains 19 species in 3 species-groups worldwide and only 2 species, viz, S. (B.) konoi and S. (B.) tokachiense, are recorded from Japan. Simulium konoi is unique among the members of the subgenus by having water dropshaped denticles on the anterior portion of the cibarium in females, which is considered as an autapomorphic character so far not found in other black flies, W or inverted V-shaped ventral plate of male genitalia, and larval thorax and abdominal segments covered with short black setae. Korean specimens of S. konoi collected from two adjacent localities can readily be recognized by denticles on the cibarium in females and well-developed ventral plate of male genitalia but showed geographical variation, e.g., lacking ventral tubercle on larval abdominal segment IX. Due to the autapomorphy and other characters found in S. konoi, the current placement of the S. konoi in the subgenus Boreosimulium or species-group assignment is tentative.

Soldanellonyx monardi (Acari, Halacaridae), a Freshwater Halacarid Species Newly Recorded from Korea

  • Shin, Jong Hak;Chang, Cheon Young
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.1
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    • pp.19-25
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    • 2021
  • Soldanellonyx monardi Walter, 1919, a halacarid species is newly recorded from South Korea, as the second member for the freshwater halacarid mites in Korea after S. chappuisi Walter, 1917 reported from Gossi-gul Cave, a limestone cave at Yeongwol in 1968. It was collected from three wells in the southeastern part of Korean peninsula this year. Korean specimens are well accorded with S. monardi s. str. in having telofemur I less than 1.5 times longer than wide, two spiniform setae on the ventral side of tibia I, relatively longer anterior dorsal plate (slightly longer than its width and about half the length of posterior dorsal plate), and the posterior epimeral plates lacking a dorsal seta. Based on the Korean specimens, a brief table for the morphological differences between adult females and deutonymphs are provided, which shows a tendency of rather consistent increment according to growth in the number of spiniform dorsal setae on telofemora and genua of legs I and II, the number of perigenital setae, and the number of genital acetabula. In this paper, detailed redescription and a brief table for the morphological differences between adult females and deutonymphs of S. monardi are provided.

Morphological Observation of Alexandrium tanarense (Lebour) Balech, A. catenella (Whedon et Kofoid) Balech and One Related Morphotype (Dinophyceae) in Korea

  • Kim, Keun-Yong;Matoko Yoshida;Yasuwo Fukuyo;Kim, Chang-Hoon
    • ALGAE
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    • v.17 no.1
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    • pp.11-19
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    • 2002
  • Twenty-nine culture strains belonging to the genus Alexandrium Halim (Dinophyceae) were established from water column or sediments in Korea. Seventeen isolates were identified as A. tamarense (Lebour) Balech, eight isolates as A. sp. cf. catenella and one as A. catenella (Whedon et Kofoid) Balech according to the presence or absence of a ventral pore, the shape of the posterior sulcal plate and the sulcal width. Three isolates were unable to be identified due to considerable distortion of thecal plates and lack of enough materials, but typical of A. tamarense and/or A. catenella. The overall cell shape of A. tamarense was usually longer than wide. The posterior sulcal plate was definitely longer than wide dorsoventrally, and sulcus extended posteriorly without apparent widening. They were distributed in three major coasts of Korea. In contrast, the cell shape of A. sp.cf. catenella was generally anterior-posteriorly flattened. The transversal axis of the posterior sulcal plate was always longer than the longitudinal, or both axes were nearly equal in length. Its sulcus was broader than that of A. tamarense and widened in the direction of antapex about 1.5 times. This morphotype existed in nearshore and offshore waters of the southern Korea sea. One of A. catenella isolates from Jinhae Bay showed no conspicuous differences with A. sp. cf. catenella except for the consistent absence of a ventral pore.

A Study Model Analysis of Complete Unilateral Cleft Lip & Palate Patients (편측성 완전 구순 구개열 환자의 구개열 형태 및 치궁의 분석)

  • Leem Dae-Ho;Kim Seung-Young;Shin Hyo-Keun
    • Korean Journal of Cleft Lip And Palate
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    • v.2 no.1_2
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    • pp.5-14
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    • 1999
  • The aim of treatment of cleft lip and palate is to correct the cleft and associated problems surgically and thus hide the anomaly so that patients can lead normal lives. This correction involves surgically producing a face that does not attract attention, a vocal apparatus that permits intelligible speech, and a dentition that allows optimal function and esthetics. In neonatal periods, gross distortion of tissues surrounding the cleft requires considerable effort and time due to post operative functional defect and scarring and induces milk feeding problem, malocclusion of deciduous or permanent dentition, congenital missing teeth, skeletal dysplasia. The occurrence of a cleft deformity is a source of considerable shock to the parents of an afflicted baby, and the most appropriate approach is very important things. Thus we tried to analysis of dental arch, shape and size of deformity in cleft patients. The results were obtained as follows. 1. When the cast measurements of UCLP subjects at first visit it was found that the mean length was 9.29mm at the alveolar cleft width, also that was 11.7mm at the anterior width and 14mm at the posterior cleft width. 2. Comparison of UCLP group at first visit and just lip surgery, it was found that the older group showed a insignificant reduction in the width of the cleft in the alveolar, canine, and tuberosity regions. 3. The maxillary casts of the UCLP group at 6 months differ Significantly from those of the at 3 months in both length and width. but there was no statistical difference except anterior ridge length of nonclefted site. 4. Comparison at 6 months and 18 months, there was a greater change in length of the alveolar cleft width, intercanine width, and anterior cleft width. Maxillary arch became wider at both the canine region and intertuberosity region. also posterior anteroposterior length was increased but anterior AP length was decreased from 8.1mm to 7.7mm. There was meaningful increase at intertuberosity length; however, a significant reduction in width t-t'

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