• The Journal of Korean Academy of Prosthodontics
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• v.34 no.1
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• pp.169-186
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• 1996

The purpose of this study was to investigate the mechanical properities and biocompatibility with crystallization temperature and time of a bioactive glass-ceramic system $41.4wt%SiO_{2}-35.0wt%CaO-3.0wt%MgO-12.0wt%P_{2}O_{5}-8.6wt%Al_{2}O_{3}$ with same molar percent of $Al_{2}O_{3}\;and\;P_{2}O_{5}$. The crystallization behaviors were investigated with DTA, XRD and SEM. Fracture toughness with the change of crystallization temperature and time was measured by indentation fracture method. Also, biocompatibility was evaluated by culture of mouse fibroblast cell line L929. The results obtained were as follows ; 1. The major crystalline phases were apatite and anorthite, and relative intensity of anorthite phase was increased at $1004^{\circ}C$. 2. The hardness and fracture toughness were gradually increased with the increase in ceraming temperature to $1004^{\circ}C$. 3. When the glass ceramic was heat-treated for 4 hours at ceraming temperature of $1004^{\circ}C$, hardness and fracture toughness showed the maximum values $578.84k/mm^2\;and\;2.07MPa\;m^{1/2}$, respectively. 4. The growth rate and cytotoxic of L929 fibroblast cells for bioactive glass ceramic were better than those of stainless steel and titanium.

• Korean Journal of Materials Research
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• v.24 no.6
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• pp.310-318
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• 2014

In this experiment, a highly porous scaffold of biphasic calcium phosphate (BCP) was prepared using the spongereplica method. The BCP scaffold was coated with 58S bioactive glass (BG) and sintered for a second time. The resulting scaffold was coated with gelatin (Gel) and cross-linked with [3-(3-dimethyl aminopropyl) carbodiimide] and N-Hydroxysuccinamide (EDC-NHS). The initial average pore size of the scaffold ranged from 300 to $700{\mu}m$, with more than 85 % porosity. The coating of BG and Gel had a significant effect on the scaffold-pore size, decreasing scaffold porosity while increasing mechanical strength. The material and surface properties were evaluated by means of several experiments involving scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-ray diffraction (XRD). Cytotoxicity was evaluated using MTT assay and confocal imaging of MC3T3-E1 pre-osteoblast cells cultured in vitro. Three types of scaffold (BCP, BCP-BG and BCP-BG-Gel) were implanted in a rat skull for in vivo evaluation. After 8 weeks of implantation, bone regeneration occurred in all three types of sample. Interestingly, regeneration was found to be greater (geometrically and physiologically) for neat BCP scaffolds than for two other kinds of composite scaffolds. However, the other two types of scaffolds were still better than the control (i.e., defect without treatment).

• Ceramist
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• v.7 no.1
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• pp.47-60
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• 2004

골 대체재에서 생체활성재라 함은 이 물질이 체내에 식립 되었을 때 표면에 사람의 뼈와 물리적, 화학적으로 매우 유사한 성질을 갖는 저결정성 탄산 아파타이트가 스스로 형성되어 이 층을 매개로 하여 섬유성 조직의 생성 없이 신생골과 직접적으로 결합하는 능력을 갖는 물질을 말한다. 이와 같은 생체활성 물질은 1970년대 초 Hench가 Na$_2$O-CaO-SiO$_2$-P$_2$O$\^$5/ 글래스계에서 처음으로 발견하였으며 이를 Bioglass$\^$ⓡ/라고 명명한데서부터 유래한다. 그 후 결정성 아파타이트가 함유된 결정화 글래스인 Ceravital$\^$ⓡ/, 고결정성 아파타이트, 아파타이트와 wollastonite 결정을 포함한 Cerabone$\^$ⓡ/, 아파타이트와 phlogophite를 함유한 Bioverit$\^$ⓡ/, MgO-CaO-SiO$_2$-P$_2$O$\^$5/ 글래스, CaO-SiO$_2$ 글래스, ${\beta}$-tricalcium phosphate, 천연 calcite 등의 다양한 세라믹 물질이 생체활성을 갖는 것으로 보고되었다.(중략)

• Journal of the Korean Ceramic Society
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• v.36 no.10
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• pp.1087-1093
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• 1999

Bioglass which is one of the surface active bionmaterials has a good biocompatibility but a poor mechanical strength, In the present work therefore two types of fluoride-containing bioglasses were coated on an alumina to improve mechanical strength. Crystallization of the coating layer and the hydroxyapatite formation on the bioactive glass coatings in tris-buffer solution were studied. When bioactive glass coated alumina was heat-treated Na2CaSi3O8 crystal was formed on the layer at lower temperature while wollastonite(CaSIO3) was obtained at higher temperature. Hydroxyapatite forming rate on the coating layer with Na2CaSi3O8 crystal was delayed with SiO2 contents in glass composition. However the hydroxyapatite was developed in 20minutes regardless SiO2 contents when the coating layer crystallized into wollastonite. More amount of P3+ ions were leached out of the coating layer with wollastonite than that with Na2CaSi3O8 crystal while Na+ and Ca2+ ions were leached out more easily from the Na2CaSi3O8 crystal containing coating layer.

• Journal of the Korean Ceramic Society
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• v.49 no.2
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• pp.146-150
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• 2012

The effects of $Al_2O_3$ on the crystallization behavior of glass compositions in the $Na_2O$-CaO-$SiO_2$ system were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The effect of $Al_2O_3$ content on the mechanical properties, density, phase formation, and microstructures of $Na_2O$-CaO-$P_2O_5$-$SiO_2$ glass ceramics were studied. The thermal parameters of each glass were studied by DTA. The density of the glass ceramic samples was measured by Archimedes' method. It was found that the glass-ceramic containing 2.0 molar percent $Al_2O_3$ had desirable sintering behavior and reached an acceptable density. Phase investigation and micro-structural analysis were performed by XRD and SEM, respectively.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.322-329
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• 1998

Chemical bonding was investigated in the simulated body fluid of several selected hydroxyapatite-containing composites. The hydroxyapatite-containing composites chemically bonded with each other in the simulated body fluid after 4 weeks. Bioglass was strongly bonded in the simulated body fluid, but bonding strength was not depended on composition. Their composite bodies were chemically bonded by heterogeneous nucleation and growth at the interfaces of the specimens in the simulated body fluid.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.52.1-52.1
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• 2011

In this work, the effect of the addition of bioactive glass in the biocompatibility and mechanical behavior of conventional TTCP/DCPA based bone cement were investigated. The cement was initially modified with chitosan and HPMC which cross-linked with citric acid to improved mechanical properties.The injectable bone substitutes were further modified by adding varying amounts of bioactive glass (0%, 10%, 20% and 30%) and its effects on the biocompatibility of the material were studied. Afterbio-glass powders were mixed with the optimized composition for HPMC and citric acid content,the IBS was incubated at $37^{\circ}C$ at different time intervals and showed progressive formation of HAp with increasing time. Mechanical properties like Vickers hardness and compressive strength were found to increase with the increasing amount of bioactive glass addition and that setting time was shortened. The fabricated IBS morphologies were further characterized using SEM. MTT assay was performed to check the cell cytotoxicity and cell proliferation for 1, 3 and 5 days. Cell morphology, adhesion and proliferation behavior of cell in the IBS by culturing MG-63 cells on the IBS for 20, 60 and 90 mins and 1, 3 and 5 days was also investigated. All the results showed increasing biocompatibility as the bioglass content increased. MTT results found the materials to be cytocompatible and SEM images showed that cells attached and proliferated successfully.

• Journal of the Korean Ceramic Society
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• v.56 no.2
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• pp.205-210
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• 2019

Bioactive glass (BG) finds limited use as a bone replacement material owing to its low mechanical properties. In order to solve this problem, the micro-sized 13-93 BG was prepared as a fabric composite with SiC microfibers, and its mechanical properties and biocompatibility were investigated in this study. The tensile strengths of BG-SiC fiber-bundle composites increased in proportion to the number of SiC fibers. In particular, even when only one SiC fiber was substituted, the tensile strength increased by 81% to 1428 MPa. In the early stage of the in-vitro test, a silica-rich layer was formed on the surface of the 13-93 BG fibers. With time, calcium phosphate grew on the silica-rich layer and the BG fibers were delaminated. On the other hand, no products were observed on the SiC fibers for 7 days, therefore, SiC fibers are expected to maintain their strength even after transplantation in the body.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.7
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• pp.87-93
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• 2010

This paper presents an evaluation of efficiency on glass precision machining by using abrasive water-jet machine. In this study, problems of conventional water-jet machining are examined experimentally and are analysized numerically. Especially, the reason of whitening on the machined surface of biochip glass is determined. It is found that the mass flow rate of abrasive input and transverse speed of water-jet are key parameters to control the direct machining of micro hole and channel on a glass substrate. Based on results of experimental analysis, possibility of direct fabrication of micro holes and channels on a glass substrate is successfully confirmed.

• Journal of the Korean Ceramic Society
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• v.37 no.11
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• pp.1105-1113
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• 2000

Bioglass 조성 중 45S5 (46.1SiO$_2$.24.4$Na_2$O.26.9CaO.2.6P$_2$O$_{5}$ : 몰비)를 기본 조성으로 하여 46P4 (46.2SiO$_2$.49.5CaO.4.3P$_2$O$_{5}$ : 몰비), 46SF (46.1SiO$_2$24.4$Na_2$O.16.1CaO.2.6P$_2$O$_{5}$.10.8CaF : 몰비) 그리고 55SF (55.1SiO$_2$.9.2$Na_2$O.27.8CaO.3.4P$_2$O$_{5}$.4.5CaF : 몰비)를 제조하여 tris-완충용액 및 유사 생체용액(simulated body fluid)에서 반응시킨 후 생체활성유리의 표면에 생성되는 아파타이트 결정형에 관하여 연구하였다. 45S5 유리를 tris-완충용액에 반응시켰을 경우 6시간 반응시부터 수산화 아파타이트가 생성되었으나 유사 생체용액에 반응시켰을 경우에는 24시간까지도 수산화 아파타이트 결정이 생성되지 못하고 비정질 상태의 칼슘 인산염만 형성되었다. tris-완충용액에 각 조성의 유리를 200시간 반응시킨 경우 불소를 함유하지 않은 유리에서는 잎사귀 모양의 수산화 아파타이트가, 불소를 함유한 유리에서는 구상의 플루오르 아파타이트가 형성되었다. 그러나 유사 생체용액에 각 조성의 유리를 200시간 반응시켰을 경우 불소를 함유하지 않은 유리에서는 누에고치형의 수산화 아파타이트가 형성되었고 불소를 함유한 유리에서는 무정형의 칼슘 인산염이 생성되었다.