• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.150-155
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• 2003

Fractures in the form of micro cracks are commonly found in natural rocks. A rock behaves in a complex way due to fracture; in particular, the anisotropic strength of a rock material is significantly influenced by the presence of these fractures. Therefore, it is essential to understand the failure mechanism of a fractured rock. In this study, a fractured rock is formulated in terms of fabric tensor based on geometric and mechanical simplifications. In this way, position, density and shape of fractures can be determined by the fabric tensor so that rocks containing multi-fractures can successfully be modeled. Also an index to evaluate the degree of anisotropy of a fractured rock is proposed. Hence, anisotropic strength of a rock containing fractures under uniaxial compression condition is estimated through a series of numerical analyses for the multi-fractured model. Numerical investigations are carried out by varying the fracture angle from $0^{\circ}\;to\;90^{\circ}$ and relationship between uniaxial compression strength and the degree of anisotropy is investigated. By comparing anisotropic strength of numerical analysis with analytic solution, this study attempts to understand the failure mechanism of rock containing fractures.

• 대한두개안면성형외과학회지
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• 제18권2호
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• pp.73-75
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• 2017

The management of mandibular angle fractures is often challenging and results in the highest complication rate among fractures of the mandible. In addition, the optimal treatment modality for angle fractures remains controversial. Traditional treatment protocols for angle fractures have involved rigid fixation with intraoperative maxillomandibular fixation (MMF) to ensure absolute stability. However, more recently, non-compression miniplates have gained in popularity and the use of absolute intraoperative MMF as an adjunct to internal fixation has become controversial. In this article, the history of, and current trends in, the treatment of mandibular angle fractures will be briefly reviewed. In addition, issues regarding the management of the third molar tooth will be discussed.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.51-54
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• 2003

Three kinds of experiments were conducted to test existing methods and develop an effective methodology for the remediation of DNAPL trapped in vertical dead-end fractures. A water-flushing method failed to remove TCE from vertical dead-end fractures where no fluid flow occurs. A water-flushing experiment implies that existing remediation methods, utilizing water-based remedial fluid such as surfactant-enhanced method, have difficulty in removing DNAPL trapped from the vertical downward dead-end fractures, because of no water flow through dead-end fractures, capillary, and gravity forces. Fluid denser than TCE was injected into the fracture network, but did not displace TCE from the vertical dead-end fractures. Base(B on the analysis of the experiments, the increase in the density of the dense fluid and the addition of surfactant to the dense fluid were suggested, and this composite dense fluid with surfactant effectively removed TCE from the vertical dead-end fractures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제44권4호
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• pp.151-158
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• 2018

Zygomatic fractures are the second most common fractures of the facial skeleton, after nasal bone fractures. Due to its uniqueness, the malar bone plays a very important role in maintaining appropriate facial contours. Zygomatic fractures can cause ocular and mandibular functional impairment, along with cosmetic defects. With the help of advanced imaging techniques and various treatment options, the management of zygomatic fractures has become more sophisticated and less invasive. This article discusses zygomatic fractures in detail: their clinical and radiographic features, and the various treatment options available.

• Knee surgery & related research
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• 제30권4호
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• pp.284-292
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• 2018

Purpose: As the number of total knee arthroplasties (TKAs) increases, the incidence of femoral periprosthetic fractures after TKA is also increasing. This review aimed to suggest a new surgically oriented classification system for femoral periprosthetic fractures. Methods: We investigated the classifications, and current treatment trends for femoral periprosthetic fractures after TKA by means of a thorough review of the relevant literature. Results: Numerous studies reported good results of surgical treatment with modern fixatives including locking compression plates and retrograde intramedullary nails. However, few classifications of femoral periprosthetic fractures reflect the recent developments in surgical treatment. Conclusions: We recommend that surgical management be considered the first-line treatment for femoral periprosthetic fractures after TKA. Our new classification will help in deciding the surgical treatment option for femoral periprosthetic fractures after TKA.

• Journal of Trauma and Injury
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• 제36권4호
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• pp.315-321
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• 2023

Pediatric carpal fractures are rare and often difficult to detect. This paper reviews the current literature on pediatric non-scaphoid carpal fractures, with a case report of a lunate fracture associated with a distal radius and ulnar styloid fracture, managed nonoperatively in a 12-year-old boy. There is lack of consensus regarding the management of these fractures due to the low number of reported cases. A frequent lack of long-term follow-up limits our understanding of the outcomes, but good outcomes have been reported for both nonoperative and operative management. This case report brings attention to the current time period for the definition of delayed union in pediatric carpal fractures, and emphasizes the need for prolonged follow-up for the detection of delayed complications leading to functional impairment.

• Journal of Trauma and Injury
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• 제37권2호
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• pp.158-160
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• 2024

Arterial thoracic outlet syndrome (TOS) resulting from thoracic trauma is an exceedingly rare condition, typically caused by a fracture of the first rib or clavicle. In this report, the author presents a case of traumatic arterial TOS precipitated by multiple left rib fractures, notably excluding the first rib, following a fall from a 2-m high stepladder. The patient was treated successfully with first rib resection via a transaxillary approach, and the postoperative course was uneventful. The literature includes no known reports of traumatic arterial TOS in patients with multiple fractures that spare the first rib, making this the first documented case of its kind. In this instance, the patient sustained fractures to the fourth and fifth ribs. The TOS was likely not a direct result of the multiple rib fractures, which were located some distance from the thoracic outlet. Rather, it is hypothesized that the trauma from these fractures caused a soft tissue injury within the thoracic outlet, which ultimately led to the development of TOS.

• Imaging Science in Dentistry
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• 제40권1호
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• pp.33-38
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• 2010

Purpose : The purpose of this study was to evaluate the diagnostic efficacy of panoramic radiographs for detection of mandibular fractures. Materials and Methods : The sample was comprised of 65 patients (55 fractured, 10 non-fractured) with 92 fracture sites confirmed by multi-detector computed tomography (CT). Panoramic radiographs were evaluated for mandibular fractures by six examiners; two oral & maxillofacial radiologists (observer A&B), two oral & maxillofacial surgeons (observer C&D), and two general dentists (observer E&F). Results : Sensitivity of panoramic radiography for mandibular fractures was 95.7% in observer A&B, 93.5% in observer C&D and 80.4% in observer E&F. The lowest sensitivity was shown in symphyseal/parasymphyseal areas, followed by subcondylar/condylar regions. Conclusion : Panoramic radiography is adequate for detection of mandibular fractures. However, additional multidetector CT is recommended to ascertain some indecisive fractures of symphysis and condyle, and in complicated fractures.

• Journal of Trauma and Injury
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• 제19권1호
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• pp.28-34
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• 2006

Purpose: In maxillofacial surgery, proper preoperative diagnosis is very important in achieving good postoperative results. Although conventional CT scans are useful for visual representations of fractures, they cannot provide direct guidance for reconstructing facial bone fractures. However, the recent technology of multislice scanning has brought many clinical benefits to CT images. Direct correlations can be made between preoperative imaging data and operative planning. The aim of the current study is to evaluate the differences between conventional CT and multidetective three-dimensional CT(3D MDCT) measurements in craniofacial deformities. Methods: From January 2005 to November 2005, MDCT scans of 41 patients were evaluated by comparing them with conventional CT scans. The 3D MDCT images were assessed and reviewed by using a simple scoring system. Results: The 3D MDCT scans offered easy interpretation, facilitated surgical planning, and clarified postoperative results in malar complex fractures, mandibular fractures, and extensive maxillofacial fractures and cranioplasty. However, 3D MDCT images were not superior to conventional CT scans in the diagnosis of blowout fractures. Conclusion: In spite of its limitations, the 3D MDCT provided additional and more comprehensive information than the conventional CT for preoperative assessment of craniofacial deformities. Therefore, the 3D MDCT can be a useful tool for diagnosis and systematic treatment planning in craniofacial skeletal deformities.

• 대한족부족관절학회지
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• 제7권1호
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• pp.68-77
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• 2003

Purpose: The treatment of calcaneal fractures remains a controversy in orthopaedic field because of its complications. The purpose of this study is to evaluate the efficacy of the treatment of calcaneal fractures and its complications. Materials and Methods: Clinical and radiological results were retrospectively analyzed in 28 patients, 34 cases with fractures of calcaneus which were treated in our department from September 1998 to march 2003. Results: According to the Creighton-Nebraska Foundation Assessment score, there were 3 excellent, 11 good, and 12 fair 6 poor results. Bohler angle was corrected from $8.3^{\circ}$ to $18.3^{\circ}$, Gissane angle was corrected from $121^{\circ}$ to $135^{\circ}$, and calcaneal width was corrected from 46.8mm to 37mm. Conclusion: Open reduction and internal fixation for joint depression type calcaneal fractures thought to be a good method of treatment. Closed reduction and percutaneous axial pinning should be chosed in selected cases of tongue type fractures. In treatment of complicated calcaneal fractures as malunion, subtalar distraction arthrodesis and lateral wall exostectomy will reduce disability of the disease.