• Journal of Periodontal and Implant Science
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• v.29 no.1
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• pp.117-130
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• 1999

All contours of the restoration not directly related to occlusion are related to the gingival tissues only.And proper contour of restoration is essential for the health of the periodontal tissues.But there are so many controversies about the contour of the restoration, and there is no uniform agreement in the literature as to which contour of restoration is best for periodontium. In general, the contour of restoration means the supragingival contour only but in the case of the intracrevicular restorative procedure the subgingival contour of restoration must be considered. Because a portion of the restoration is placed in a gingival sulcus which is extremely vulnerable to periodontal disease. In this article the concepts or theories of the supragingival contour, the subgingival contour, and the emergence profile were discussed.The contour of the restoration and the biotype of the periodontium must be considered in intracrevicular restorative procedure.And sufficient tooth preparation is important factor to develop the proper contour of restoration which is kind to periodontium.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.1
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• pp.72-82
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• 2008

Various surgical approaches in the mandibular condyle fracture have been reported and many advantages of intraoral reduction were also introduced. But there are still controversies about surgical method of condylar fractures up to date. To establish the surgical approach protocol of condylar fracture, from May 2001 to December 2004, total 65 patients with 74 fractures of the mandibular condyle were reviewed during 2 years, retrospectively. All cases were classified according to the treatment considering factors, such as the level of fracture, degree and direction of displacement of fractured segment, patient’s age and gender, surgical approach methods, and their complications. Especially, advantages and surgical limitations of extraoral surgical approach, such as direct reduction and fixation via submandibular approach, Nam’s method, and endaural approach, were compared with those of intraoral surgical approach, such as direct intraoral reduction with transbuccal fixation or right angle driver system, and intraoral reinsertional approach after extraoral fixation of fractured fragment. The guidelines of surgical approach of condylar fracture based on our clilnical retrospective experiences and literature reviews can be suggested.

• Imaging Science in Dentistry
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• v.41 no.2
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• pp.43-51
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• 2011

Purpose : The purpose of this article is to review the current status of dental caries diagnosis using cone beam computed tomography (CBCT). Materials and Methods : An online PubMed search was performed to identify studies on caries research using CBCT. Results : Despite its usefulness, there were inherent limitations in the detection of caries lesions through conventional radiograph mainly due to the two-dimensional (2D) representation of caries lesions. Several efforts were made to investigate the three-dimensional (3D) image of lesion, only to gain little popularity. Recently, CBCT was introduced and has been used for diagnosis of caries in several reports. Some of them maintained the superiority of CBCT systems, however it is still under controversies. Conclusion : The CBCT systems are promising, however they should not be considered as a primary choice of caries diagnosis in everyday practice yet. Further studies under more standardized condition should be performed in the near future.

• Advances in pediatric surgery
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• v.15 no.2
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• pp.173-179
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• 2009

Congenital thoracic malformations such as intra- and extra-pulmonary sequestration, cystic adenomatoid malformation, congenital pulmonary airway malformation, malinosculation, bronchogenic cyst, reduplication cyst, and foregut cyst are frequently detected on routine prenatal ultrasound. There are some controversies about treatment for postnatally persistent pulmonary sequestration. Some authors recommend expectant long term follow up but most authors advocate elective surgical excision because of complication such as respiratory distress, infection, intrathoracic bleeding, haemoptysis, cardiac failure, and potential risk of malignancy. We experienced 2 cases of prenatally diagnosed extrapulmonary sequestration which were located in the subdiaphragmatic retroperitoneum. Resections were performed at 2 months and 4 months of age using intraabdominal approach. There were no complications. In conclusion, if the prenatally diagnosed extrapulmonary sequestration remained postnatally, early operation might reduce morbidity related to extrapulmonary sequestration and parental anxiety without any postoperative complication.

• Journal of The Korean Association For Science Education
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• v.17 no.2
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• pp.163-178
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• 1997

The purpose of this study is to investigate the effect of categorizing activities in lessons on improving critical thinking to meet energy environment issues in every day situation, supposing that there are not only scientific concepts but also critical thinking ability in scientific literacy to meet social controversies related with science intelligently. Categorizing Activity Program was developed and applied to the 10th grades(n=51) in Seoul for about one month. The program was consisted of two domains. They studied science concepts of various aspects of science, technology and society related with energy and environment in the first and second domain repectively, in the while, two critical tasks which include articles from newspapers and magazines were assigned to them for the development and evaluation of critical thinking abilities. The scores of critical thinking ability, the cognitive element, and critical thinking inclination, the affective element, were increased meaningfully(p<.05). In conclusion, categorizing activity as a strategy of concept attainment was effective in improving critical thinking for seeing various aspects with various view points needed in controversial issues related with energy and environment.

• Korean Journal of Social Welfare
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• v.64 no.1
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• pp.299-324
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• 2012

After social service voucher schemes were introduced in Korea, many controversies have been concentrated on market-based approach, which encourage competition and choice while amount of funding, number of providers, and types of services have been rapidly expanded. This also could mean that transform of social service paradigm from provider-centered approach to user-cantered approach, one of the trends found internationally. Therefore, this is the study to reveal development of social service discourses in Britain where various models of social services have been attempted in their modern history. Then, through the historical analysis, the trends toward more user-cantered approach were found to be distinguished based on the division of individualism and collectivism. This could provide theocratical implication to the current discussion on social services in Korea.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.349-352
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• 2005

The energy management of an HEV using optimal control and global optimization is thought to be closest to the best operation of the system. However, there are some controversies on the ways of defining the optimization problems and constituting the optimal control simulators. Here, we presented a simulator which adopts the concept of equivalent fuel economy and leads the vehicle to run in a more efficient way. In order to realize the optimal operation of the HEV and check the validity of the control logics, we also developed a forward-facing simulator. The simulator was developed with the Cruise and MATLAB co-simulation interface. Especially, neural network controller was used for the hybrid control module in the simulator. With the simulator, the optimal operation could be converted into hybrid control rules and the validity of the operation was verified.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.219-240
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• 2009

Since NF-${\kappa}B$ has been identified as a transcription factor associated with immune cell activation, groups of researchers have dedicated to reveal detailed mechanisms of nuclear factor of ${\kappa}B$ (NF-${\kappa}B$) in inflammatory signaling for decades. The various molecular components of NF-${\kappa}B$ transcription factor pathway have been being evaluated as important therapeutic targets due to their roles in diverse human diseases including inflammation, cystic fibrosis, sepsis, rheumatoid arthritis, cancer, atherosclerosis, ischemic injury, myocardial infarction, osteoporosis, transplantation rejection, and neurodegeneration. With regards to new drugs directly or indirectly modulating the NF-${\kappa}B$ pathway, FDA recently approved a proteasome inhibitor bortezomib for the treatment of multiple myeloma. Many pharmaceutical companies have been trying to develop new drugs to inhibit various kinases in the NF-${\kappa}B$ signaling pathway for many therapeutic applications. However, a gene knock-out study for $IKK{\beta}$ in the NF-${\kappa}B$ pathway has given rise to controversies associated with efficacy as therapeutics. Mice lacking hepatocyte $IKK{\beta}$ accelerated cancer instead of preventing progress of cancer. However, it is clear that pharmacological inhibition of $IKK{\beta}$ appears to be beneficial to reduce HCC. This article will update issues of the NF-${\kappa}B$ pathway and inhibitors regulating this pathway.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.1
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• pp.30-37
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• 1995

The prognosis of parosteal osteosarcoma is better than any other malignant bone tumors, but there are many controversies in its treatment. We tried to evaluate the prognosis and the effectiveness of limb-salvage operation in the treatment of the parosteal osteosarcoma. We experienced 12 patients of conventional parosteal osteosarcoma(2 males and 10 females) from 1981 to 1991. The limb-salvage operations with wide resection margin were done in 8 patients(5 tumer prosthesis, 2 resection arthrodesis and 1 vascularized fibular transplantation), marginal en-bloc resection and amputation in 2 patients, respectively. The duration of mean follow up was 5 years and 9 months, ranging from 2 year-3 months to 11 years, except of the patient who died with metastasis 1 year 8 months after. The disease-free survival rate(DFSR) of all patients was 68% and that of the patients treated with limb-salvage operation was 88% at 7 years. The DFSR was 33% with marginal margin(3 cases) and 89% with wide margin(9 cases) at 7 years. The results were unsatisfactory in the conventional parosteal osteosarcoma treated with marginal resection. The limb-salvage operation with wide surgical margin was thought to be the treatment of choice.

• Korean Journal of Computational Design and Engineering
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• v.13 no.1
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• pp.58-66
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• 2008

The artificial discs have recently used to preserve the motion of the treated segment in lumbar spine surgery. However, there have been lack of biomechanical information of the artificial discs to explain current clinical controversies such as long-term results of implant wear and excessive facet contact forces. In this study, we investigated the biomechanical effects of three artificial implants on the lumbar spinal segments by finite element analysis. The finite element model of intact lumbar spine(L1-S) was developed and the three implants were inserted in L4-L5 segment of the spine model. 5 Nm of flexion and extension moments were applied on the superior plate of L1 with 400 N of compressive load. Excessive motions and high facet contact forces at the surgical level were generated in the all three implanted models. In the flexion, the peak von-Mises stresses in the semi-constrained type implant was higher than those in the un-constrained type implant which would cause wear on the polyethylene core. The results of the study would provide a biomechanical guideline for selecting optimal surgical approach or evaluating the current design of the implants, or developing a new implant.