• 대한치과기공학회지
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• 제40권3호
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• pp.183-190
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• 2018

Purpose: The purpose of this study was to evaluated the process of model analysis, design, and production for a full mouth prosthetic rehabilitation of function, esthetics, and pronunciation. Methods: This is a case report of class III malocclusion with a severe anterior incisor occlusion and a prosthetic treatment of patient with poor occlusion of posterior teeth. A provisional restoration based on the diagnostic wax-up was applied to the patient. And then functions, esthetics, and occlusal stability were observed during 4 week tracking period. Final restorations were delivered and evaluated based on a systematic analysis, diagnosis and treatment plan. Results: We confirms that this case study obtained the satisfactory results in terms of functions and esthetics. Conclusion : If we can give the patient the continuous evaluation and progress monitoring, we expect the dentist and the dental technician to design the prosthesis successfully.

• 디지털산업정보학회논문지
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• 제8권1호
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• pp.55-64
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• 2012

The advantage of direct volume rendering is to visualize structures of interest in the volumetric data. However it is still difficult to simultaneously show interior and exterior structures. Recently, cone beam computed tomography(CBCT) has been used for dental diagnosis. Despite of its usefulness, there is a limitation in the detection of interior structures such as pulp and inferior alveolar nerve canal. In this paper, we propose an efficient volume rendering model for visualizing important interior as well as exterior structures of dental CBCT. It is based on the concept of illustrative volume rendering and enhances boundary and silhouette of structures. Moreover, we present a new method that assigns a different color to structures in the rear so as to distinguish the front ones from the rear ones. This proposed rendering model has been implemented on graphics hardware, so that we can achieve interactive performance. In addition, we can render teeth, pulp and canal without cumbersome segmentation step.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.173.2-173.2
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• 2005

• Imaging Science in Dentistry
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• 제43권3호
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• pp.153-161
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• 2013

Purpose: To prevent low bone mineral density (BMD), that is, osteoporosis, in postmenopausal women, it is essential to diagnose osteoporosis more precisely. This study presented an automatic approach utilizing a histogram-based automatic clustering (HAC) algorithm with a support vector machine (SVM) to analyse dental panoramic radiographs (DPRs) and thus improve diagnostic accuracy by identifying postmenopausal women with low BMD or osteoporosis. Materials and Methods: We integrated our newly-proposed histogram-based automatic clustering (HAC) algorithm with our previously-designed computer-aided diagnosis system. The extracted moment-based features (mean, variance, skewness, and kurtosis) of the mandibular cortical width for the radial basis function (RBF) SVM classifier were employed. We also compared the diagnostic efficacy of the SVM model with the back propagation (BP) neural network model. In this study, DPRs and BMD measurements of 100 postmenopausal women patients (aged >50 years), with no previous record of osteoporosis, were randomly selected for inclusion. Results: The accuracy, sensitivity, and specificity of the BMD measurements using our HAC-SVM model to identify women with low BMD were 93.0% (88.0%-98.0%), 95.8% (91.9%-99.7%) and 86.6% (79.9%-93.3%), respectively, at the lumbar spine; and 89.0% (82.9%-95.1%), 96.0% (92.2%-99.8%) and 84.0% (76.8%-91.2%), respectively, at the femoral neck. Conclusion: Our experimental results predict that the proposed HAC-SVM model combination applied on DPRs could be useful to assist dentists in early diagnosis and help to reduce the morbidity and mortality associated with low BMD and osteoporosis.

• 한국치위생학회지
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• 제13권4호
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• pp.623-629
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• 2013

Objectives : The aim of the study is to investigate the health belief model affecting the oral health behavior in elementary school students by applying health belief model. Methods : Subjects were 216 elementary school students including 6th grade 103 boys and 113 girls in Gyeonggi-do from February 1 to February 28, 2013. They completed self-reported questionnaires after receiving informed consents. Results : Oral health belief model showed cues to action($20.39{\pm}3.11$), benefits($19.63{\pm}3.37$), self-efficacy($16.62{\pm}2.60$), severity($14.53{\pm}3.94$), susceptibility($14.31{\pm}4.62$), and barrier($11.74{\pm}3.85$). Oral health belief revealed the lower the level of barrier(p=0.004) and the higher cues to action, Benefits and self-efficacy were the best oral health behavior(p=0.000). The most influencing factors of oral health belief were self-efficacy(0.267) and Cues to action(0.239). Conclusions : Children's oral health belief is associated with oral health behavior. children's self efficacy and cues to action toward oral care influenced on oral behavior. It is important to enhance the recognition toward self efficacy and cues to action by following recommended behavior and effective health educational program.

• Restorative Dentistry and Endodontics
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• 제41권4호
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• pp.255-261
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• 2016

Objectives: This study aimed to analyze the mineral composition of naturally- and artificially-produced caries-affected root dentin and to determine the elemental incorporation of resin-modified glass ionomer (RMGI) into the demineralized dentin. Materials and Methods: Box-formed cavities were prepared on buccal and lingual root surfaces of sound human premolars (n = 15). One cavity was exposed to a microbial caries model using a strain of Streptococcus mutans. The other cavity was subjected to a chemical model under pH cycling. Premolars and molars with root surface caries were used as a natural caries model (n = 15). Outer caries lesion was removed using a carbide bur and a hand excavator under a dyeing technique and restored with RMGI (FujiII LC, GC Corp.). The weight percentages of calcium (Ca), phosphate (P), and strontium (Sr) and the widths of demineralized dentin were determined by electron probe microanalysis and compared among the groups using ANOVA and Tukey test (p < 0.05). Results: There was a pattern of demineralization in all models, as visualized with scanning electron microscopy. Artificial models induced greater losses of Ca and P and larger widths of demineralized dentin than did a natural caries model (p < 0.05). Sr was diffused into the demineralized dentin layer from RMGI. Conclusions: Both microbial and chemical caries models produced similar patterns of mineral composition on the caries-affected dentin. However, the artificial lesions had a relatively larger extent of demineralization than did the natural lesions. RMGI was incorporated into the superficial layer of the caries-affected dentin.

• 대한의생명과학회지
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• 제26권2호
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• pp.93-100
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• 2020

Xerostomia is a relatively common oral disease that causes various problems such as pain, discomforted, tissue damage, and infection. When the activity of AQPs, which plays an important role in the microbial channel transmembrane activity in tissues, decreases saliva secretion and the oral cavity dryness occurs. In this study, we observed whether there was a change in tissue through the expression level of AQP-5 in the submandibular gland in the 4-DAMP-induced xerostomia model. First, in order to construct a xerostomia model, 4-DAMP (1 mg/kg) and 20% urethane (0.5 mL/kg) were administered intraperitoneal (i.p.) to experimental animals. To observe the changes in the submandibular gland was excised, H&E staining was performed and protein quantitation analysis was performed using the submandibular tissue to observe the changes in AQP5 protein expression involved in changes in saliva secretion. Also, cinnamaldehyde (5, 12.5, 25 and 50 mg/kg) dissolved in 20% DMSO, in distilled water for each concentration, and then orally administered at a dose of 1 mL for biopsy and protein quantitative analysis. As a result, it was observed that the submandibular tissue, a model of xerostomia was wider than the naïve group. And then western blot analysis, the expression level of AQP5 decreased in the 4-DAMP group compared to the naïve group, and the expression increased in the group administered orally with cinnamaldehyde. Therefore, administration of 4-DAMP resulted in histological changes for xerostomia, and cinnamaldehyde would be a material that can be developed by reducing xerostomia.

• Biomolecules & Therapeutics
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• 제25권3호
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• pp.259-265
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• 2017

This study aimed to investigate the analgesic effect of substance P (SP) in an animal model of neuropathic pain. An experimental model of neuropathic pain, the chronic constriction injury (CCI) model, was established using ICR mice. An intravenous (i.v.) injection of SP (1 nmole/kg) was administered to the mice to examine the analgesic effects of systemic SP on neuropathic pain. Behavioral testing and immunostaining was performed following treatment of the CCI model with SP. SP attenuated mechanical allodynia in a time-dependent manner, beginning at 1 h following administration, peaking at 1 day post-injection, and decaying by 3 days post-injection. The second injection of SP also increased the threshold of mechanical allodynia, with the effects peaking on day 1 and decaying by day 3. A reduction in phospho-ERK and glial fibrillary acidic protein (GFAP) accompanied the attenuation of mechanical allodynia. We have shown for the first time that i.v. administration of substance P attenuated mechanical allodynia in the maintenance phase of neuropathic pain using von Frey's test, and simultaneously reduced levels of phospho-ERK and GFAP, which are representative biochemical markers of neuropathic pain. Importantly, glial cells in the dorsal horn of the spinal cord (L4-L5) of SP-treated CCI mice, expressed the anti-inflammatory cytokine, IL-10, which was not seen in vehicle saline-treated mice. Thus, i.v. administration of substance P may be beneficial for improving the treatment of patients with neuropathic pain, since it decreases the activity of nociceptive factors and increases the expression of anti-nociceptive factors.

• International Journal of Stem Cells
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• 제11권2호
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• pp.177-186
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• 2018

Background and Objectives: Glial scarring and inflammation after spinal cord injury (SCI) interfere with neural regeneration and functional recovery due to the inhibitory microenvironment of the injured spinal cord. Stem cell transplantation can improve functional recovery in experimental models of SCI, but many obstacles to clinical application remain due to concerns regarding the effectiveness and safety of stem cell transplantation for SCI patients. In this study, we investigated the effects of transplantation of human mesenchymal stem cells (hMSCs) that were genetically modified to express Olig2 in a rat model of SCI. Methods: Bone marrow-derived hMSCs were genetically modified to express Olig2 and transplanted one week after the induction of contusive SCI in a rat model. Spinal cords were harvested 7 weeks after transplantation. Results: Transplantation of Olig2-expressing hMSCs significantly improved functional recovery in a rat model of contusive SCI model compared to the control hMSC-transplanted group. Transplantation of Olig2-expressing hMSCs also attenuated glial scar formation in spinal cord lesions. Immunohistochemical analysis showed that transplanted Olig2-expressing hMSCs were partially differentiated into Olig1-positive oligodendrocyte-like cells in spinal cords. Furthermore, NF-M-positive axons were more abundant in the Olig2-expressing hMSC-transplanted group than in the control hMSC-transplanted group. Conclusions: We suggest that Olig2-expressing hMSCs are a safe and optimal cell source for treating SCI.

• Anatomy and Cell Biology
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• 제51권4호
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• pp.236-242
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• 2018

The dog frontal sinus may represent an alternative model dental implant research; its topographical resemblance to the maxillary sinus renders it a potentially favorable experimental environment. The aim of this study was thus to elucidate the anatomical configuration of the canine frontal sinus and histological characteristics, and to determine whether it could be a new canine experimental model for dental implant research. Twenty-four sides of canine frontal bones were harvested. The distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was measured with the aid of Lucion software. The thicknesses of the canine frontal sinus wall were measured, and the two specimens stained with hematoxylin and eosin. The mean distance from the nasion to the emerging point of the lateral aspect of the canine frontal sinus was 16.0 mm. The mean thicknesses of the canine frontal bone at 3, 6, 9, 12, and 15 mm lateral to the midsagittal plane were 2.3, 2.7, 3.2, 3.8, and 3.7 mm, respectively. The canine frontal sinus was lined with pseudostratified ciliated columnar epithelium. These data suggest that the canine frontal sinus is a suitable alternative to the canine maxillary sinus as a model for studying various sinus augmentation protocols.