• The Journal of Advanced Prosthodontics
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• v.4 no.3
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• pp.146-152
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• 2012

PURPOSE. The cortical bone thickness on the anterior region is important for achieving implant stability. The purpose of this study was to examine the thickness of the cortical and cancellous bones on the anterior region of the maxilla and mandible. MATERIALS AND METHODS. Twenty-five cadaver heads were used (16 male and 9 female; mean death age, 56.7 years). After the long axis of alveolar process was set up, it was measured in 5 levels starting from 2 mm below the cementoenamel junction (L1) at intervals of 3 mm. All data was analysed statistically by one-way ANOVA at the .05 significance level. RESULTS. The cortical bone thickness according to measurement levels in both the labial and lingual sides increased from L1 to L5, and the lingual side below L3 was significantly thicker than the labial side on the maxilla and mandible. In particular, the labial cortical bone thickness in the maxilla was the thinnest compared to the other regions. The cancellous bone thickness according to measurement levels increased from L1 to L5 on the maxilla, and on the mandible it was the thinnest at the middle level of the root. CONCLUSION. For implant placement on the anterior region, a careful evaluation and full knowledge on the thickness of the cortical and cancellous bone are necessary, therefore, these results may provide an anatomic guideline to clinicians.

• Journal of Veterinary Clinics
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• v.35 no.3
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• pp.107-110
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• 2018

A 5-year-old Thoroughbred race horse was presented to Busan Korea Racing Authority equine hospital with a 3-year history of a slow-growing left rostral maxillary mass. The location and progressive growth of the mass eventually resulted in poor food prehension, quidding and mouth bit placement. The mass was solitary and hard, and covered by normal smooth oral mucosa. Radiographic examination of the maxillae showed a flocculated and mixed radiolucent lesion protruding outward and displacing the 202 and 203 teeth caudally. The 202 tooth was in normal size and the 203 tooth was hypoplastic on radiography. Under general anesthesia, a partial surgical resection of the mass was performed to minimize functional loss and facilitate prompt return to track. After surgery, there was improvement in food intake, mouth bit placement, and cosmetic appearance. Histopathological examination determined the resected maxillay mass to be an ossifying fibroma. However, there was continued growth of remnant mass in the maxilla. Equine ossifying fibroma is a rare condition and primarily affects the rostral mandible, and less commonly, the maxillae. In this case, the lesion was slow-growing, and caused cosmetic and functional impairments, including poor food intake and reduced trainability. Surgical resection was performed, but the effect of treatment was limited due to advanced size / stage of the tumor. Early dental care is suggested for horse owners to prevent belated identification and improve successful treatment of oral disorders like ossifying fibroma.

• The Journal of Advanced Prosthodontics
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• v.16 no.1
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• pp.1-11
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• 2024

PURPOSE. The present experiment aimed to evaluate the placement accuracy of fully guided implant surgery using a mucosa-supported surgical guide when the protocol of osteotomy and installation was modified (MP) compared to when the protocol was sequentially and conventionally carried out (CP). MATERIALS AND METHODS. For 24 mandibular dentiform models, 12 dentists (6 experts and 6 beginners) performed fully guided implant placements two times at the right first and second molar sites using a mucosa-supported surgical guide, once by the CP (CP group) and at the other time by the MP (MP group). The presurgical and postsurgical stereolithographic images were superimposed, and the deviations between the virtually planned and actually placed implant positions and the procedure time were compared statistically (P < .05). RESULTS. The accuracies were similar in the CP and MP groups. In the CP group, the mean platform and apex deviations at the second molar site for the beginners were +0.75 mm and +1.14 mm, respectively, which were significantly larger than those for the experts (P < .05). In the MP group, only the mean vertical deviation at the second molar site for the beginners (+0.53 mm) was significantly larger than that for the experts (P < .05). The procedure time was significantly longer for the MP group (+94.0 sec) than for the CP group (P < .05). CONCLUSION. In fully guided implant surgery using a mucosa-supported guide, the MP may improve the placement accuracy when compared to the CP, especially at sites farther from the most-posterior natural tooth.

• Journal of Advanced Technology Convergence
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• v.3 no.3
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• pp.47-56
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• 2024

This study analyzes the field practicum experiences of adult learners in social welfare and discusses areas for improvement. The field practicum is an essential process and training course for becoming a social worker. Through the practicum experience, learners gain a valuable opportunity to apply theoretical knowledge in real-world settings and understand their future roles as prospective social workers. However, if the field practicum does not adequately reflect the characteristics of adult learners, it may be difficult to ensure a successful practicum experience. For adult learners to successfully complete their social welfare practicum, integrated and consistent support from both the university and practicum institutions is essential. In particular, the challenges adult learners may face, such as difficulties in time management, psychological stress, and the gap between theory and practice, must be addressed. Most importantly, thorough preparation before the practicum is necessary to ensure success.

• The Journal of Advanced Prosthodontics
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• v.2 no.3
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• pp.102-105
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• 2010

PURPOSE. The aims of this study were to suggest a method of fabrication of the record base using a light-polymerized resin by applying the two-phase fabrication method for the improvement of the fit of the record base and to compare the degree of fit according to the separation site. MATERIALS AND METHODS. In the edentulous cast of maxilla, four test groups were considered. In the first, second, third, and fourth test groups (n = 12 in each group) the separation was done at 0, 5, 10, and 15 mm, respectively below the alveolar crest along the palatal plane. For the control group, the record base was made without separating the two sections. The light-body silicone material was injected into the fitting surface of the record base. It was then placed onto the cast and finger pressure was applied to stabilize it in a seated position followed by immediate placement onto the universal test device. Finally, the mass of the impression material was measured after it was removed. ANOVA was performed using the SAS program. For the post-hoc test, the Wilcoxon Rank-Sum test and the Tukey-Kramer HSD test were performed ($\alpha$ = 0.05). RESULTS. The control group and Group 3, 4 showed significant differences. The Group 3 and 4 showed significantly smaller inside gaps than the control group which was not made with the two-phase fabrication method. CONCLUSION. The two-stage polymerized technique can improve the fit of the denture base particularly when the separation was made at 10 to 15 mm from the alveolar crest.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.419-424
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• 2012

This paper discusses the state-of-the-art techniques in real-time state estimation for the Smart Microgrids. The most popular method used in traditional power system state estimation is a Weighted Least Square(WLS) algorithm which is based on Maximum Likelihood(ML) estimation under the assumption of static system state being a set of deterministic variables. In this paper, we present a survey of dynamic state estimation techniques for Smart Microgrids based on Belief Propagation (BP) when the system state is a set of stochastic variables. The measurements are often too sparse to fulfill the system observability in the distribution network of microgrids. The BP algorithm calculates posterior distributions of the state variables for real-time sparse measurements. Smart Microgrids are modeled as a factor graph suitable for characterizing the linear correlations among the state variables. The state estimator performs the BP algorithm on the factor graph based the stochastic model. The factor graph model can integrate new models for solar and wind correlation. It provides the Smart Microgrids with a way of integrating the distributed renewable energy generation. Our study on Smart Microgrid state estimation can be extended to the estimation of unbalanced three phase distribution systems as well as the optimal placement of smart meters.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.55-63
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• 2016

Calculation of the core neutronic parameters is one of the key components in all nuclear reactors. In this research, the energy spectrum and spatial distribution of the neutron flux in a uranium target have been calculated. In addition, sensitivity of the core neutronic parameters in accelerator-driven subcritical advanced liquid metal reactors, such as electron beam energy ($E_e$) and source multiplication coefficient ($k_s$), has been investigated. A Monte Carlo code (MCNPX_2.6) has been used to calculate neutronic parameters such as effective multiplication coefficient ($k_{eff}$), net neutron multiplication (M), neutron yield ($Y_{n/e}$), energy constant gain ($G_0$), energy gain (G), importance of neutron source (${\varphi}^*$), axial and radial distributions of neutron flux, and power peaking factor ($P_{max}/P_{ave}$) in two axial and radial directions of the reactor core for four fuel loading patterns. According to the results, safety margin and accelerator current ($I_e$) have been decreased in the highest case of $k_s$, but G and ${\varphi}^*$ have increased by 88.9% and 21.6%, respectively. In addition, for LP1 loading pattern, with increasing $E_e$ from 100 MeV up to 1 GeV, $Y_{n/e}$ and G improved by 91.09% and 10.21%, and $I_e$ and $P_{acc}$ decreased by 91.05% and 10.57%, respectively. The results indicate that placement of the Np-Pu assemblies on the periphery allows for a consistent $k_{eff}$ because the Np-Pu assemblies experience less burn-up.

• Journal of Digestive Cancer Research
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• v.3 no.1
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• pp.39-41
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• 2015

We report a case of long term survival on trastuzumab based treatment. A 51-year-old man with dyspepsia received esophagogastroduodenoscopy on another hospital and was transferred for further evaluation under the impression of advanced gastric cancer, Borrmann type III, antrum, lesser curvature. After further studies in our hospital, the patient was diagnosed with advanced gastric cancer, adenocarcinoma, moderately differentiated with pancreas invasion and lymph node metastasis. Though he was recommended with chemotherapy, he refused and left for oriental herbal medicine. After 4 months, the patient was admitted through emergency room for hematemesis. Diagnosed with gastric outlet obstruction due to gastric cancer in the antrum, he underwent the placement of pyloric metal stent insertion. Immunohistochemical staining showed HER2-positive finding, and he was treated with palliative chemotherapy of trastuzumab, capecitabine, and cisplatin, 16 times during 11 months. The patient showed neutropenia after the therapy, so cisplatin was left out, and he received combination chemotherapy of trastuzumab and capecitabine, 34 times during 25 months. Response evaluation showed no remarkable change in extent of primary stomach cancer, lymph node metastasis, and regression of metastasis site, and the patient is continuing chemotherapy.

• Journal of Periodontal and Implant Science
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• v.28 no.1
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• pp.177-185
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• 1998

Periodontal disease and/or loss of teeth brings pathologic tooth migration that can result in esthetic and occlusal problems. Diastema and general spacing of the teeth, particularly in the anterior segments of the dentition are frequently developed in individuals with advanced periodontal disease. Thus, the overall treatment plan for a patent with advanced periodontal disease often involves periodontal orthodontic combined therapy. Orthodontic treatment in adults with periodontal disease is restricted to tooth alignment with special caution. Indirect bonding can achieve accurate bracket placement. A 38 year old woman with adult periodontitis was treated by periodontal therapy. Subsequently, her diastema was orthodontically corrected by indirect bonding technique. It must be an appropriate case report of periodontal-orthodontic combined therapy.

• Polymer(Korea)
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• v.32 no.3
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• pp.213-218
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• 2008

About 17% of historical properties in Korea were made of stones and most of them are exposed to weathering, as such that discoloring, cracking, and shattering occur from physical, chemical, mechanical, and biological effects due to outdoor placement. Proper treatments for conservation are necessary to prevent the weathering damage and to retain the original shape of stones. MMA, an acrylic monomer having low viscosity can be impregnated deep inside stones by consecutive compression and decompression process in a pressurized vessel. After the polymerization of MMA impregnate, the space inside of the stone was filled with PMMA. It is expected that water repellent and weather resistant properties will be improved because of the improved bonding of constituent materials in stones. In this study, moisture absorption, chemical resistance, and mechanical property of two domestic granites were examined after treating them with MMA for the purpose of determining the conservation value of this method that was possibly useful to the conservation of stone cultural assets.