• Journal of Korean Foot and Ankle Society
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• v.3 no.1
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• pp.58-61
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• 1999

Isolated fracture dislocation of the tarsal navicular bone is extremely rare. The mechanism of injury of this fracture dislocation is known as a horizontal or axial load on plantar flexed foot. Closed or open reduction is recommended for displaced navicular fracture. We report one case of isolated fracture dislocation of the tarsal navicular which was treated with closed reduction and percutaneous K-wire fixation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.51-57
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• 2011

The lightweight and compact actuator with high power is required to perform motion with multiple degrees of freedom. To reduce the size and inertia of a robot manipulator, the mechanical transmission system is used. The shape memory alloy(SMA) is similar to the muscle-tendon-bone network of a human hand. However, there are some drawback and nonlinearity, such as the hysteresis and the stress dependence. In this paper, the design of the underactuated robot hand is studied. The 3-finger dexterous hand is driven by the SMA actuator using segmental mechanism. This digital approach enables to overcome the nonlinearity of SMA wire. The translational displacement of SMA actuator required to bend a phalanx of the underactuated robot hand is estimated and the bending angle of the underactuated robot hand according to input displacement of SMA actuator is predicted by the multi-body dynamic analysis.

• Journal of Korean Foot and Ankle Society
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• v.23 no.1
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• pp.39-41
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• 2019

An isolated dislocation of the intermediate cuneiform bone is a rare midfoot injury. This paper reports a case of a 60 year old man who fell from a height with his foot in the plantar flexed position. An isolated dorsal dislocation of the intermediated cuneiform was confirmed. Good results were obtained after an open reduction and internal fixation with a Lisfranc screw and Kirschner wire.

• Clinics in Shoulder and Elbow
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• v.23 no.4
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• pp.198-202
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• 2020

Simple clavicle fractures can achieve satisfactory results through conservative treatment, and the less frequency of nonunion. Non-union or malunion can occur in displaced clavicle fractures or comminuted shaft fractures. Treatment of displaced comminuted clavicle shaft fractures is performed by holding together the free fragments with interfragmentary screws or wires and fixing them to the clavicle with a plate. Therefore, we performed interfragmentary fixation using open reduction and internal fixation with bioresorbable screws (Mg-Ca alloy, Resomet bioresorbable bone screw; U&I Corp.) and bioresorbable wires (Mg-Ca alloy, Resomet bioresorbable K-wire and pin, U&I Corp.) for displaced comminuted clavicle fractures (Robinson type 2B) and additionally used a metal plate. We expected decreased irritation and infection due to absorption after surgery. We report four cases that were treated in this way.

• Journal of Periodontal and Implant Science
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• v.47 no.3
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• pp.143-153
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• 2017

Purpose: The aim of the present exploratory study was to evaluate extraction socket healing at sites with a history of periodontal and endodontic pathology. Methods: The mandibular 4th premolar teeth in 5 adult beagle dogs served as experimental units. Periodontal and endodontic lesions were induced in 1 premolar site in each animal using wire ligatures and pulpal exposure over 3 months (diseased sites). The contralateral premolar sites served as healthy controls. The mandibular 4th premolar teeth were then extracted with minimal trauma, followed by careful wound debridement. The animals were sacrificed at days 1, 7, 30, 60, and 90 post-extraction for analysis, and the healing patterns at the healthy and diseased extraction sites were compared using radiography, scanning electron microscopy, histology, and histometry. Results: During the first 7 days of healing, a significant presence of inflammatory granulation tissue was noted at the diseased sites (day 1), along with a slightly accelerated rate of fibrin clot resolution on day 7. On day 30, the diseased extraction sites showed a greater percentage of persistent fibrous connective tissue, and an absence of bone marrow formation. In contrast, healthy sites showed initial signs of bone marrow formation on day 30, and subsequently a significantly greater proportion of mature bone marrow formation on both days 60 and 90. Radiographs exhibited sclerotic changes adjoining apical endodontic lesions, with scanning electron microscopy showing collapsed Volkmann canals protruding from these regions in the diseased sites. Furthermore, periodontal ligament fibers exhibited a parallel orientation to the alveolar walls of the diseased sites, in contrast to a perpendicular arrangement in the healthy sites. Conclusions: Within the limitations of this study, it appears that a history of periodontal and endodontic pathology may critically affect bone formation and maturation, leading to delayed and compromised extraction socket healing.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.228-235
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• 2004

The development and proliferation of the mandibular condyle can be altered by changes in the biomechanical environment of the temporomandibular joint. The biomechanical loads were varied by feeding diets of different consistencies. The purpose of the present study was to determine whether changes of masticatory forces by feeding a soft diet can alter the trabecular bone morphology of the growing mouse mandibular condyle, by means of micro-computed tomography. Thirty-six female, 21 days old, C57BL/6 mice were randomly divided into two groups. Mice in the hard-diet control group were fed standard hard rodent pellets for 8 weeks. The soft-diet group mice were given soft ground diets for 8 weeks and their lower incisors were shortened by cutting with a wire cutter twice a week to reduce incision. After 8 weeks all animals were killed after they were weighed. Following sacrifice, the right mandibular condyle was removed. High spatial resolution tomography was done with a Skyscan Micro-CT 1072. Cross-sections were scanned and three-dimensional images were reconstructed from 2D sections. Morphometric and nonmetric parameters such as bone volume(BV), bone surface(BS), total volume(TV), bone volume fraction(BV/TV), surface to volume ratio(BS/BV), trabecular thickness(Tb. Th.), structure model index(SMI) and degree of anisotropy(DA) were directly determined by means of the software package at the micro-CT system. From directly determined indices the trabecular number(Tb. N.) and trabecular separation(Tb. Sp.) were calculated according to parallel plate model of Parfitt et al.. After micro-tomographic imaging, the samples were decalcified, dehydrated, embedded and sectioned for histological observation. The results were as follow: 1. The bone volume fraction, trabecular thickness(Tb. Th.) and trabecular number(Tb. N.) were significantly decreased in the soft-diet group compared with that of the control group (p<0.05). 2. The trabecular separation(Tb. Sp.) was significantly increased in the soft-diet group(p<0.05). 3. There was no significant differences in the surface to volume ratio(BS/BV), structure model index(SMI) and degree of anisotropy(DA) between the soft-diet group and hard-diet control group (p>0.05). 4. Histological sections showed that the thickness of the proliferative layer and total cartilage thickness were significantly reduced in the soft-diet group.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.711-721
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• 1997

The purpose of this study was to investigate the stress distribution and intensity derived from the transpalatal lingual arch in the investing bone composed of photoelastic material(PL-3). The transpalatal lingual arch wire was deflected in the horizontal and vertical direction to give the various conditions. The two-dimensional photoelastic stress analysis was performed, and the stress distrebution was recored by photography The results were as follows: 1. In bilateral expansion, as horizontal deflection was singly applied, the stress was more concentrated on the root apex in square free end than round. In square free end, as vertical deflection was increased gradually, the black line meaning center of rotation moved inferiorly together with the increment of whole fringes. 2. In application of vertical deflection on anchorage side for unilateral expansion, the stress distribution that expansive force leaned to expansion side was observed. As vortical deflection increased, the extruding stress was observed on molar of expansion side. And as horizontal deflection increased, the tipping stress on the molar of anchorage side was observed. 3. In unilateral rotation with the asymmetric toe-in, the fringe appeared on the distal aspect of root apex.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.1
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• pp.49-60
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• 2005

The Back Bone of gearing portion between Core Network System which is used in wire and wireless system is No.7 Protocol. ISUP( ISDN User Part), INAP handling in Intelligent Network and MAP gearing method for linking each Network Element System in mobile network have use of No.7 signaling. Therefore, it is require for system to detect the problem - operating problem occurs in Core Network which use No.7 signaling or the existing problem that is not recognized - in shortest time. This paper study out analyzing and measuring system for No.7 protocol and analyzing out system whether out of order or not. It can abstract No.7 Signaling Message and analyze system performance and report it. This system is connected in system No.7 HW Module which is in charge of No.7 Signaling. It is not offer Emulator function and Simulation function for any scenario but offer monitoring No.7 signaling. This system perform the function about No.7 MTP, ISUP, INAP and MAP and is offered several wire and wireless network Operator. It can detect and correct SW system, HW system and operating system problem. From now on, this system may offer the function about A-interface which is gearing between BSC and MSC, so it will perform to analyze generally and prompt effective operating for Core Network system.

• Journal of Korean Foot and Ankle Society
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• v.15 no.3
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• pp.149-152
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• 2011

Purpose: The Akin osteotomy which is a closing wedge osteotomy of the proximal phalanx widely used for the correction of hallux valgus has several methods of fixation. we tried to report the effects of the fixation using an absorbable suture material during the Akin osteotomy for the hallux valgus. Materials and Methods: This study was based on 448 cases of 346 patients who were able for follow-up more than 12 months among the patients who had an Akin osteotomy together with the surgery of hallux valgus between March of 2006 and May of 2010. Absorbable suture material had been used in all cases. Radiologically displacement and union of osteotomy site were observed after the surgery, and clinically postoperative complication such as skin irritation, pain and satisfaction were investigated. Results: Radiologically all cases had showed complete union and no case had the loss of an correction due to loss of fixation. Also, any case had no skin irritation due to a knot. Three cases had a medial cortical breakage due to a strong knot, and the initial one case among them had additionally fixed the osteotomy site for four weeks using K-wire, and the remaining two cases had fixed a suture on an articular surface without any fixation of an additional wire. If a medial cortical bone was lost by carrying out an ostectomy due to proximal protrusion of proximal phalanx, three cases could show union through the fixation of suture on an articular surface. Conclusion: This study considers that the fixation of the osteotomy site using an absorbable suture material in an Akin osteotomy was effective method and the advantage of this procedure was unnecessity of the material removal and no skin irritation.

• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.969-982
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• 1994

This study was designed to investigate the stress distribution, intensity and force mechanism derived from the MEAW by photoelastic stress analysis of the artificial teeth and surrounding bone composed of photoelastic material(PL-3) The findings of this study were as follows, 1. In case of no elastic on the MEAW with tip back, the moderate stress was observed on the molar and canine area, and the light stress was observed on the other area. 2. In case of the vertical elastic on the plain A.W, and the MEAW without tip back, the great stress was observed on the lateral incisor area, but on the MEAW with tip back, the moderate stress was observed on the anterior area and molar area. 3. In case of the C III elastic on plain A.W., the stress was concentrated on the anterior area hanged by elastic but on the MEAW without tip back, the stress was transmitted equally from the anterior area to the posterior teeth area. On the MEAW with tip back, the great stress was observed on the anterior and molar area. 4. In case of the C III elastic on the plain A.W., the stress was concentrated on the posterior area hanged by elastic but on the MEAW without tip back, the stress was transmitted equally from the posterior area to the anterior area. On the MEAW with tip back, the great stress was observed on the posterior area and the moderate stress was observed on the anterior area.