• The Journal of Advanced Prosthodontics
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• v.6 no.3
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• pp.241-244
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• 2014

Fabricating a crown to retrofit an existing abutment tooth for a partial removable dental prosthesis (PRDP) is one of the most time-consuming and labor-intensive clinical procedures. In particular, when the patient is concerned with esthetic aspects of restoration, the task of fabricating becomes more daunting. Many techniques for the fabrication of all-metallic or metal-ceramic crowns have been discussed in the literature. This article was aimed to describe a simple fabrication method in which a retrofitting crown was fabricated for a precise fit using a ceramic-pressed-to-metal system.

• Journal of the Korean Ceramic Society
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• v.42 no.11 s.282
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• pp.770-776
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• 2005

Hardening and hydroxyapatite(HAp) formation behavior of the bioactive cements in the system of $CaO-SiO_{2}-P_{2}O_{5}$ glasses and the corresponding glass-ceramics were studied. DCPD (Dicalcium Phosphate Dihydrate: $CaHPO_4{\cdot}2H_2O$) and DCPA (Dicalcium Phosphate Anhydrous: $CaHPO_4$) were developed when the prepared glass and glass-ceramic powders were mixed with three different solutions. The DCPD and DCPA transformed to HAp when the cement was soaked in Simulated Body Fluid (SBF), and this HAp formation strongly depended on the releasing capacity of $Ca^{2+}$ ions from the cements. The glass-ceramic containing apatite showed fast setting, but no HAp formation was observed because no $Ca^{2+}$ ions were released from this glass-ceramics. The compressive strength of the cements increased with reaction time in SBF until all DCPD and DCPA transformed to HAp.

• Journal of the Korea Safety Management & Science
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• v.7 no.1
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• pp.211-222
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• 2005

The ceramic forming materials are getting more important recently since they are used widely in repairing metal structures, welded metal structures and mechanical components etc. The determination of elastic constants for ceramic coating materials takes much time and efforts in experiment due to the brittleness of ceramic material itself. The aim of this research is to determine the Young's Modulus for ceramic metal coating material. In order to achieve the goal, the hybrid method which uses impulse hammer technique for experimental method and modal analysis of finite element method for computational method was used. The results show good agreement with existing experimental data on Young's Modulus.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.529-532
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• 2005

The effects of polymer-binder ratio and ceramic powder content on the drying shringage and strength of polymer-modified pastes using redispersible polymer powders and ceramic powder are examined. As a result, the drying shrinkage of the polymer-modified pastes using redispersible polymer powders tend to decrease with increasing polymer-binder ratio and ceramic powder content. Regardless of the type of polymer powder, the tensile strength and adhesion in tension of the polymer-modified pastes with ceramic powder tend to increase with increasing polymer-binder ratio and ceramic powder content.

• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.1060-1066
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• 2001

Water-based alumina tapes for application of all-ceramic crowns were fabricated using PVP as binder that is biocompatible, highly soluble in solvents, and no residue leftafter firing. Tensile strength of alumina tapes was governed by binder/(binder+plasticizer)ratio. On the other hand, linear shrinkage and density were determined by alumina/(alumina+organic) ratio. Composite for all-ceramic crowns, prepared by infiltration of a glass into sintered porous alumina, showed high flexural strength which increased with increasing sintered density.

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.147-156
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• 1989

The effects of starting composition, sintering temperature and porosity on the mechanical properties of hydroxyapatite ceramics were investigated. The hydroxyapatite powder were prepared by precipitation method using Ca(NO3)2.4H2O and (NH4)2.HPO4. The obtained powders were Ca-deficient hydroxyapatites and as the Ca/P mole ration in the initial solution was increased, the particle size of the precipitates was decreased, and the decomposition of hydroxyapatite to $\beta$-TCP was controlled. The porosity, as well as Ca/P mole ratio in starting composition and sintering temperature, plays major role in the mechanical properties of dense hydroxyapatite ceramics.

• Journal of the Korean Ceramic Society
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• v.40 no.9
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• pp.832-836
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• 2003

Multi-layer ceramic composites were prepared by tape casting followed by hot pressing using silicon nitride layer with silicon nitride whiskers, silicon nitride layer with silicon carbide particles and boron nitride-alumina layer. The whiskers were aligned during the casting. As the whisker content of the silicon nitride layer was increased up to 10 wt％, the flexural strength of the multi-layer composite was increased. However, further increase of the whisker content in the layer resulted in a rapid decrease of the strength of the composite. The results suggest that the strength of multi-layer ceramic composite showing non-catastrophic failure behavior can be significantly improved by incorporating the aligned whiskers in the layers.

• Journal of the Korean Ceramic Society
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• v.17 no.1
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• pp.13-19
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• 1980

Mineral identifications on halloysite in Hadong-Sancheong area and the halloysite bearing clay ii Yeoju, Yesan and Hampyeong-Muan area are carried out by the method of X-ray diffraction, electron microscopy and DTA. Chemical composition of the above minerals are analyzed by means of X-ray-fluorescence. Refractoriness are also measured by refractoriness tester. A standard diagram for quantitative analysis of halloysite is given.

• Journal of the Korean Institute of Rural Architecture
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• v.3 no.2
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• pp.1-12
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• 2001

This study is about the residential district structure of Gyeryong ceramic art village in Gyeryong ceramic art village is a residential district for potters who succeed to and develop Gyeryong ceramic art. The external appearance of Gyeryong ceramic art village seems like being fixed and simplified. The creative space is either detached or attached to a living room. The relation between inner and outer space is that is directly connected to a garden. In the characters of major spaces, the formation of a workshop is the most important part of a house. And, an exhibition equipment and an oven are connected to the workshop. According to the study, a house, which is designed without an architect's help is simple and has a different form from a house designed by an architect.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.116-121
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• 2009

The constituent phases in Ti($C_{0.7}N_{0.3}$)-xWC-20Ni (wt%, x=5, 15, 25) cermets were characterized using nanoindentation in conjunction with observation of microstructure. The microstructure of cermet is composed of hard phase and binder phase, which gave rise to a wide range of hardness distribution when nanoindentation was carried out on the polished surface of cermets. Because of the inhomogeneous nature of cermet microstructure, observation of indented surface was indispensable in order to separate the hardness of each constituent phase. The measured values of hardness using nanoindentation were ${\sim}14\;GPa$ for the binder phase and ${\sim}24$ to 28 GPa for the hard phase, of which nanoindentation hardness was decreased with the addition of WC into Ti($C_{0.7}N_{0.3}$)-Ni system. In addition, the nanoindentation hardness of Ni binder phase was much higher than reported Vickers hardness, which could result from confined deformation of binder phase due to the surrounding hard phase particles.