• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.3
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• pp.463-469
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• 1996

Sonoring is caused by the repeated obstructions of versatile upper air way structure during sleep and is known as a kind of disease entity varing from simple snoring to obstructive sleep apnea syndrome(OSAS) which can cause serious cardiopulmonary complications due to its hypoxic pathophysiology. It has been reported that over 30% of middle-aged person have the problems of snoring and its accompanied symptomes and signs. Cephalometric measurements, frequently used to measure sella-nasion-subspinale(SNA) and sella-nasion-supramentale(SNB) angles, can provide the informations about the posterior airway space(PAS), the mandibular plane(MP) and the position of hyoid bone. These informations are useful in determining the therapeutic modalities of the snoring and OSAS patients. However, with conventional routine upright position, it does not represent the actual images of obstructive mechanism during sleep but only show the images of awaken normal upper airway anatomy. Therefore we have taken dual images of a routine upright lateral and a supine cephalometric view to compare both.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.38
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• pp.28.1-28.6
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• 2016

Backgrounds: Insufficient intermaxillary space is caused by non-restoration following tooth extraction in the past, and this involves eruption of the opposing teeth and changes of the arch structure. Such cases are difficult just by a simple prosthetic approach, and diversified treatment plans should be established. Among these, posterior maxillary segmental osteotomy (PMSO) is an efficient treatment option than extraction of opposing teeth as it surgically repositions multiple erupted teeth and alveolar bone. PMSO can preserve the natural teeth; therefore, it is being regarded as a treatment method which can improve insufficient intermaxillary space significantly. Case presentation: In this case report, the first patient received PMSO in order to place an implant in the mandibular edentulous space after decreased vertical dimension is restored, and the second patient received PMSO along with orthodontic treatment to obtain the intermaxillary space and balance the interarch molar width. Conclusion: PMSO is the treatment of choice when occlusion is compromised in the presence of decreased vertical dimension or arch length discrepancy.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1172-1176
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• 1997

Since Virchow first introduced the term myxoma to describe a tumor that recapitulates the structure of the umbilical cord, it has been increasingly recognized that many diverse neoplasms may acquire a similar myxoid appearance. Myxoma have evolved within the pathology literature from tumors often described in practically all sites to the currently recognized subtypes restricted to the heart, skin, soft tissue, and bone. Pulmonary myxoma is extraordinary rare. We experienced pulmonary myxoma in a 63 year old man. The pulmonary radiology showed mass in right upper lung field, and percutaneous transthoracic needle lung biopsy was performed to confirm the myxoma.

• Applied Microscopy
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• v.26 no.2
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• pp.177-195
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• 1996

Fine structure of the processes of intramembranous ossification and endochondral ossification at the tip of the distal phalanx of human fetuses was studied by electron microscopy. In 50 mm fetus, intramembranous ossification of the tip of cartilaginous phalanx was first noted. The osteoblasts of the perichondral zone of tip of cartilaginous phalanx started to lay down a thick membranous bony lamella. Most of the hypertrophied chondrocytes in the marginal parts of tip of the distal phalanx remained viable after being embeded in mineralized cartilaginous septa. The tuberosity of the distal phalanx was formed by membranous bony trabeculae on the exterior of the subperiosteal cap at 80 mm fetus. At this stage endochondral ossification was first observed in distal extremity of the distal phalanx. The maority of hypertrophied chondrocytes in the center of distal extremity appeared to be disintegrating. Resorption of calcified matrix was undertaken by perivascular cells and chondroclasts. From the periosteum, zone of calcification, vascular sprouts expanded within a recently opened lacunae, and the invading osteoblasts laid down osteoid and bone. After 120 mm fetus, endochondral and subperiosteal ossification proceeded in only one direction, just proximally. These findings demonstrate that intramembranous ossification, calcification, and endochondral ossification start at tip of the distal phalanx instead of at the center of the shaft, as was the case in other long bones.

• Archives of Reconstructive Microsurgery
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• v.22 no.2
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• pp.52-56
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• 2013

Purpose: We had proceeded seven iIpsilateral dorsalis pedis vascularized pedicle flaps in the distal leg and foot to cover the restricted size defects and followed-up average for 5 years and 9 months to evaluate the survival rate, neurosensory function and cosmesis in final results. Materials and Methods: From January 1999 through October 2012, we have performed iIpsilateral dorsalis pedis vascularized pedicle flaps in the distal leg and foot to cover the restricted size defect (average around $3.6{\times}2.4cm$) in 7 cases and average age was 41.6 years (21.5 to 59.0 years). Lesion site was posterior heel in 4 cases, distal anterior leg in 3 cases. Donor structure was the dorsalis pedis artery and the first dorsal metatarsal vessel and deep peroneal nerve in 3 cases and the dorsalis pedis artery and the first dorsal metatarsal vessel in 4 cases. Results: Seven cases (100%) were survived and defect area was healed with continuous dressing without skin graft. The sensory function in the neurovascular flap was restored to normal in 3 cases. Cosmesis was good and fair in 7 cases (85.7%). Conclusion: Ipsilateral dorsalis pedis vascularized pedicle flap in the distal leg and foot is one of the choice to cover the exposed bone and soft tissues without microsurgical procedure.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.915-918
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• 2005

Advances in Information Technology and in Biomedicine have created new uses for CAD technology with many novel and important biomedical applications. Such applications can be found, for example, in the design and modeling of orthopedics, medical implants, and tissue modeling in which CAD can be used to describe the morphology, heterogeneity, and organizational structure of tissue and anatomy. CAD has also played an important role in computer-aided tissue engineering for biomimetic design, analysis, simulation and freeform fabrication of tissue scaffolds and substitutes. And all the applications require precision geometry of the organs or bones of each patient. But the geometry information currently used is polygon model with none solid geometry and is so rough that it cannot be utilized for accurate analysis, simulation and fabrication. Therefore a case study is performed to deduce a transformation method to build free form surface from a rough polygon data or medical images currently used in the application. This paper describes the transformation procedure in detail and the considerations for accurate organ modeling are discussed.

• Journal of Biomedical Engineering Research
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• v.31 no.6
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• pp.427-433
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• 2010

Although tracking methods are efficient and popular for vessel segmentation, they require a seed to initiate an instance of tracking. In this paper, a new method to detect new seeds for tracking of arterial segments from CT angiography (CTA) and to construct a vascular structure is proposed. The proposed algorithm is based on shape analysis of connected components in a volume of interest around a vessel segment which was already extracted by tracking. The eigenvalues of the covariance matrix are used as the shape features for detection. The experimental results on actual clinical data showed that the results totally revealed the arterial tree not hindered by bone or veins. In visual comparison to a method which combines registration and subtraction of both pre-contrast and post-contrast CT volumes, the proposed method produced comparable results to the reference method and were confirmed of its feasibility for clinical use of reducing the cost and burden of patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.577-585
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• 1994

The Twin Blocks technique was developed by Dr. William Clark of Scotland during the early 1980's. Twin Blocks are an uncomplicated system that incorporates the use of upper and lower bite blocks. These blocks reposition the mandible and redirect occlusal forces to achieve rapid correction of malocclusions. They are also comfortable and the patients wear them full-time-inducing eating time. Occlusal forces transmitted through the dentition provide a constant proprioceptive stimulus to influence the rate of growth and the trabecular structure of the supporting bone. The features of Twin Blocks mean easier and quicker treatment. The occlusal inclined plane is the fundamental functional mechanism of the natural dentition. Twin blocks are bite blocks that effectively modify the occlusal inclined plane to induce favorably directed occlusal forces by causing a functional mandibular displacement. Upper and lower bite blocks interlock at a $45^{\circ}$ angle and are designed for full-time wear to take advantage of all functional forces applied to the dentition including the forces of mastication. The patients who were treated with modified Twin Blocks, and following results were observed: 1. Large overjet and deep overbite were corrected. 2. Class II molar relationship was changed into Class I. 3. Labial inclination of upper incisors was corrected by adjustment of labial bow of upper bite block. 4. The profiles of two patients were improved by anterior displacement of mandible.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1265-1270
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• 2007

Conventional methods for fabricating three-dimensional (3-D) scaffolds have substantial limitations. In this paper, we present 3-D scaffolds that can be made repeatedly with the same dimensions using a microstereolithography system. This system allows the fabrication of a pre-designed internal structure, such as pore size and porosity, by stacking photopolymerized materials. The scaffolds must be manufactured in a material that is biocompatible and biodegradable. In this regard, we synthesized liquid photocurable biodegradable TMC/TMP, followed by acrylation at terminal ends. And also, solidification properties of TMC/TMP polymer are to be obtained through experiments. Cell adhesion to scaffolds significantly affects tissue regeneration. As a typical example, we seeded chondrocytes on two types of 3-D scaffold and compared the adhesion results. Based on these results, the scaffold geometry is one of the most important factors in chondrocyte adhesion. These 3-D scaffolds could be key factors for studying cell behavior in complex environments and eventually lead to the optimum design of scaffolds for the regeneration of various tissues, such as cartilage and bone.

• Archives of Plastic Surgery
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• v.32 no.2
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• pp.255-258
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• 2005

The nasopalatine duct cyst, known as the incisive canal cyst, is the most common nonodontogenic cyst in the maxillofacial area. It is believed to arise from epithelial remnants of the embryonic nasopalatine duct. Nasopalatine duct cysts are most often detected in patients between forties and sixties. The trauma, bacterial infection, or mucous retention has been suggested as etiological factors. The cysts often present as asymptomatic swelling of the palate but can present with painful swelling or drainage. Radiologic findings include a well demarcated cystic structure in a round, ovoid or heart shape presenting with a well-defined bone defect in the anterior midline of the palate between and posterior to the central incisors. Most of them are less than 2cm in size. On MRI, the cyst is identified as a high-intensity, well-marginated lesion, which indicates that it contains proteinaceous material. We experienced a case of a 61-year-old female patient who had a $2.3{\times}2.6{\times}1.7cm$ sized nasopalatine duct cyst. The bony defect after a surgical extirpation was restored with hydroxyapatite. So we report a good results with some reviews of the literatures.