• Restorative Dentistry and Endodontics
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• v.34 no.4
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• pp.350-355
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• 2009

Bond strength depends on characteristics of bonding surface and restorative technique. The majority of studies dealing with dentin bond strength were carried out on flat bonding surface, therefore, difference of bond strength between axial wall and pulpal wall is not clear yet. This study evaluated bonding difference between cavity walls in class I composite resin restoration with different filling techniques. Twenty extracted caries-free human third molars were used. Cavities were prepared in 6 ${\times}$4 ${\times}$3 mm box-type and divided into four groups according to filling technique and bonding surface: Group I; bulk filling - pulpal wall, Group II; bulk filling - axial wall, Group III; incremental filling - pulpal wall, Group IV; incremental filling - axial wall. Cavities were filled with Filtek $Z250^{(R)}$(3M/ESPE., USA) and Clearfill SE $bond^{(R)}$(Kuraray, Japan). After 24 hour-storage in $37^{\circ}C$water, the resin bonded teeth were sectioned bucco-lingualy at the center of cavity. Specimens were vertically sectioned into 1.0 ${\times}$1.0 mm thick serial sticks perpendicular to the bond surface using a low-speed diamond saw (Accutom 50, Struers, Copenhagen, Denmark) under water cooling. The trimmed specimens were then attached to the testing device and in turn, was placed in a universal testing machine (EZ test, Shimadzu Co., Kyoto, Japan) for micro-tensile testing at a cross-head speed of 1 mm/min. The results obtained were statistically analyzed using 2-way ANOVA and t-test at a significance level of 95%. The results were as follows: 1. There was no significant difference between bulk filling and incremental filling. 2. There was no significant difference between pulpal wall and axial wall, either. Within the limit of this study, it was concluded that microtensile bond strength was not affected by the filling technique and the site of cavity walls.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.383-396
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• 2000

Before the advent of early plastic or maxillofacial reconstructive surgery, facial features could only be replaced and mimicked by prosthetic, artificial means. Facial deformity or dysfunction, whether congenital or acquired by trauma or mutilating disease, has long been an area of constant research, development and innovation in many cultures of the world. One of the greatest contributors to the need for maxillofacial prosthetics has been physical conflict and warfare. The use of maxillofacial prostheses is not merely the replacement of a missing or disfigured aspect of the face, but the rehabilitation of that individual back into the society from which they originate. Rehabilitation includes the restoration of the person's self worth and confidence, not just physically but psychologically. In sixteenth century, Ambroise Pare, French military surgeon, first have tried many maxillofacial prosthetics for injured war soldiers with papier-mache, silver, gold and copper. According to patient's demand who lost their maxillofacial figures, maxillofacial personnel have increased and prosthetic's skill have been advanced all of the world. Over the last decade, there has been a very rapid development in technical possibilities to provide patients with facial prostheses retained by skin penetrating implants. This article will present overall history of maxillofacial prostheses and some background information on the materials used from the old world. And to overcome still many limitation of prosthetic, new minds and new ideas for technique and materials should be developed.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.11
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• pp.116-122
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• 1998

We propose a spatially adaptive image interpolation algorithm, which can restore high frequency details in the original high resolution image. In order to apply the regularization approach to the interpolation procedure, we first present a two-dimensional separable image degradation model for a low resolution imaging system. According to the model, we propose a regularized spatially adaptive interpolation algorithm by using five different constraints. We also analyze convergence of the proposed algorithm, and provide some experimental results to compare the proposed algorithm with its nonadaptive version.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.1
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• pp.19-23
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• 2008

Purpose: Several methods of anatomical reconstruction for chronic lateral ankle instability has been reported to avoid the problems of nonanatomical reconstruction. Precise reconstruction of the normal anatomy is essential to the restoration of normal joint mechanics and stability. The problem with anatomical reconstruction is that it is very difficult to reconstruct the normal anatomic course of the ligaments. We thought making one tunnel at the fibular attachment of anterior talofibular ligament and calcaneofibular ligament was more anatomical than making separate tunnels for each ligaments because the two ligaments are contiguous. In this article, the basis of anatomical reconstruction of the lateral ankle ligaments was reviewed and a technique of reconstruction using semitendinosus was introduced.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.249-255
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• 2011

Purpose: Placement of endosseous implants in the atrophic maxilla is often restricted because of the lack of supporting bone. In this article, augmentation of the maxillary sinus floor with deproteinized bovine bone to enable insertion of endosseous implants is described. The technique is aimed at providing a cortical layer on top of the graft to ensure a reliable seal of the maxillary sinus and to achieve optimal stability of the bone graft in case of simultaneously placement of dental implants. Methods: The procedure was used in 200 patients (839 implants), using deproteinized bovine bone. The mean follow-up was 28.5 months. No inflammation of the bone grafts nor of the maxillary sinus occurred. The patients received implant supported overdentures or bone-anchored bridges. Results: The survival rate of implant restoration of this study was 97.6%. The total average of marginal bone loss in radiographs was $0.20{\pm}0.38$ mm. Insufficient primary stability, bony quality, and infection were thought to be associated factors in the failed cases. Conclusion: This study documented that deproteinized bovine bone, when used as a grafting material for augmentation of the sinus floor, may lead to proper osseointegration of a endosseous implant.

• The Journal of the Korean dental association
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• v.51 no.5
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• pp.250-254
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• 2013

Modern theories and concepts of occlusion for implants and natural teeth have originated in complete denture construction. Bilateral balanced occlusion as the occlusal scheme of choice has a long history in complete denture construction. The reason that occlusion has always been a consideration in the provision of removable prosthetics is because the adoption of good occlusal practice has a significant and immediate impact on the overall success of the treatment, as it affects denture stability. However, clinicians must remember that there are multiple ways, both successful and unsuccessful, to complete the restoration of a patient's occlusion. The goal is to meet the physiologic, functional, and esthetic needs of the individual patient while applying knowledge, accurate diagnosis, experience, clinical judgement, and attention to detail. This paper describes the features of an ideal occlusion in removable prosthodontics, why these features make it ideal for denture stability, and some technique for achieving these aims.

• Journal of Periodontal and Implant Science
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• v.40 no.3
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• pp.139-143
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• 2010

Purpose: Pink gingival esthetic especially on the anterior teeth has been an important success criterion in implant-supported restoration. Inter-implant papillae are a critical factor for implant esthetics, and various techniques for inter-implant papilla reconstruction have been introduced. The aim of this study is to suggest and evaluate a surgical technique for reconstructing inter-implant papillae. Methods: A 28-year-old man had an implant placed on the #13 and #14 area. Four months after implant placement, a second stage surgery was planned for inter-implant papilla reconstruction. At the time of the abutment connection, I-type incisions were performed on the #13i & #14i area followed by full-thickness flap elevation and connection of a healing abutment on underlying fixtures without suture. Results: Two weeks after the second stage implant surgery, soft tissue augmentation between the two implants was achieved. Conclusions: I-shaped incisions for papilla reconstruction performed during the second stage implant surgery were useful for inter-implant papilla reconstruction and showed a good esthetic result.

• ETRI Journal
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• v.30 no.3
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• pp.377-382
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• 2008

A novel power amplifier for a polar transmitter is proposed to achieve better spectral performance for a wideband envelope signal. In the proposed scheme, 2-bit sigma-delta (${\Sigma}{\Delta}$) modulation of the envelope signal is introduced, and the power amplifier configuration is modified in a binary form to accommodate the 2-bit digitized envelope signals. The 2-bit ${\Sigma}{\Delta}$ modulator lowers the noise of the envelope signal by fine quantization and thus enhances the spectral property of the RF signal. The Ptolemy simulation results of the proposed structure show that the spectral noise is reduced by 10 dB in a full transmit band of the EDGE system. The dynamic range is also enhanced. Since the performance is improved without increasing the over-sampling ratio, this technique is best suited for wireless communication with high data rates.

• 대한두경부종양학회:학술대회논문집
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• 2007.05a
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• pp.80-84
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• 2007

Background and Objectives : The radial forearm free flap is a useful reconstructive method of surgical defects after oral and oropharyngeal tumor resection. We evaluated the swallowing and speech outcomes of radial forearm free flap reconstruction for oral and oropharyngeal cancers. Materials and Methods : We retrospectively reviewed clinical data of 84 patients who underwent reconstructive surgery for oral or oropharyngeal cancer using radial forearm free flap from August 1994 to January 2007. Modified barium swallowing (MBS) was done in 100 patients and speech-language assessment was done in 23 patients by a speech-language pathologist. Results were analyzed according to the swallowing functions and the speech-language assessments. Results : According to the results of MBS which was done postoperatively, aspiration occurred in three patients and velopharyngeal insufficiency occurred in four patients who had been reconstructed with multilobed free flap due to large mucosal defects. There was one patient who exhibited severe articulation impairment out of 23 patients. However, 19 patients out of 23 patients showed excellent intelligibility in speech. Conclusion : We concluded that the radial forearm free flap technique is an excellent reconstructive method for the restoration of palatal and pharyngeal function in oral and oropharyngeal cancer patients.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.229-234
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• 2006

On May 31, 2003. Landsat 7 experienced an anomaly causing the Scan Line Corrector(SLC) to stop functioning normally. The SLC-off causes individual scan lines to alternately overlap and then leave large gaps at the edge of the Image. A many scientists with ongoing experience using ETM+ data evaluated the scientific usability and validity of Landsat 7 products containing the SLC anomaly The best reference scene for gap-filling is the other SLC-on Landsat scene that provide same resolution, few changes, and similar data acquisition. But receiving of Landsat imagery is not stable in Korea. So SPOT image can be another alternative solution because it is a steady-state multispectral satellite image as Landsat image. In this study, we filled the SLC-off gap s of 2, 3, 4 bands using SPOT image by a local regression technique, and assigned the optimum spectral value to gaps of 1, 5, 7 bands based on a spectral adjacency. Through this process, we could restore Landsat SLC-off image and evaluated the accuracy of the results.