• 대한치과기공학회지
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• 제25권1호
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• pp.21-28
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• 2003

The purpose of this study was to process bio-active glass ceramic composite, reinforced with sapphire fibers, by hot press. Also to study the interface of the matrix and the sapphire fiber, and the mechanical properties. Glass raw materials melted in Pt crucible at 1300$^{\circ}C$ during 3.5 hours. The melt was crushed in ball mill and then crushed material, ground and sieved to $<40{\beta}{\mu}m$. Sapphire fibers cut (30mm) and aligned. Powder and fibers hot pressed. The micrographs show good bonding between the matrix and the fiber and no porosity in the glass matrix. This means ideal fracture phenomena. Glass is fractured before the fiber. This is indication of good fracture strength. EDXS showing aluminum rich phase and crystalline phase. Bright field image of the matrix showing crystalline phase. Also diffraction pattern of TEM showing the crystalline phase and more than one phase. Strength of the samples was determined by 3 point bend testing. Strength of the 10vol% sample was approximately 69MPa, while strength of the control sample is 35MPa. Conclusions through this study as follow: 1. Micrographs show no porosity in the glass matrix and the interface. 2. The interface between the fiber and the glass matrix show no gaps. 3. Fracture of the glass indicates characteristic fiber-matrix separation. 4. Presence of crystalline phase at high processing temperature. 5. Sapphire is compatible with bioactive glass.

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.173-192
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• 1999

The purpose of this study was to evaluate the effects of bioactive glass and natural coral on the human periodontal ligament fibroblast(HPLF) behaviors during the regeneration process of peridontium. To determine the cellular events occuring in the presence of the particles of bioactive glass and natural coral, HPLF were isolated from healthy premolar teeth extracted for orthodontic treatment. Cells were cultured in ${\alpha}$MEM at 37$^{\circ}C$, 5% $CO_2$, 95% humidity incubator. Bioactive glass and natural coral were powdered, and each particles(<40${\mu}$m) were placed on the cultured cells at the concentration of 0.3mg/ml, and 1,0mg/ml for experimental group. In control group no particles were added. And each group was evaluated by examining the cell morphology under phase-contrast micrograph at 4 day and transmission electron micrograph(TEM) and scanning electron micrograph(SEM) at 14 day, alkaline phosphatase activity at 5 and 9 day, protain synthesis at 4 day, DNA synthesis at 1, 2, 3 and 4 day, cell proliferation at 1, 3, 5,7 and 9 day and the formation of bone nodule at 30 day after culturing all groups in mineralizing supplemented mediun, No significant changes in cell morphology by adding these two matirials were found under phase contrast microscopy and TEM. HPLF phagocytocized each particles suggesting that HPLF is involved in the process of resorbing each particles and that bioactive glass were more biocompatible than natural coral. The ALPase activity of bioactive glass 0.3 mg/ml was similar with control groups and all the rests of control groups were significantly low(P<0.01) indicating a transient dedifferentiation of HPLF in the presence of bioactive glass and natural coral particles. There were no significant differences of protein synthesis between all groups. The DNA synthesis in experimental groups were significantly lower than control groups at 1, 2 and 3 day (P<0.01) but became similar to control groups at 4 day. Between control groups, the DNA synthesis in bioactive glass O.3mglml group was significantly higher than other groups(P<0.01). Cell proliferation in natural coral 1.0mg/ml and bioactive glass 1.0mglml groups were significantly lower than control group at 3 day(P<0.05) and there were no differences at 5, 7, 9 day. There were more bone nodule formation in experimental groups than in control groups. In conclusion, these results indicated that bioactive glass and natural coral have some effects of a transient dedifferentiation on HPLF and regeneration of periodontal tissues, however any significant cytotoxic effect on HPLF by these two particles were not found.

• 한국세라믹학회지
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• 제42권11호
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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 Korean Association of Oral and Maxillofacial Surgeons
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• 제26권6호
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• pp.613-619
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• 2000

The purpose of the present study was to investigate the effect of Bioactive glass on bone regeneration in the experimental mandibular bone defects. Five rabbits, weighing about 2.0kg, were used. Three artificial bone defects, $5{\times}5{\times}5mm$ in size, were made at the inferior border of the mandible. In the experimental group 1, the bone defect was grafted with $Biogran^{(R)}$ and covered with $Bio-Gide^{(R)}$ resorbable membrane. In the experimental group 2, $Biogran^{(R)}$ was grafted only. In the control group, the bone defect was filled with blood clot and was spontaneously healed. The animals were sacrificed at 1, 2, 4, and 8 weeks after the graft. Microscopic examination was performed. Results obtained were as follows: In the control group, the osteoid tissue was observed at week 1 and the bone trabeculi were connected each other and matured at week 2. The lamellar bone formation appeared at week 4, and the amount of bone tissue was increased at week 8. In the experimental group 1, the fibrous tissue was filled between the granules of Bioactive glass and the cartilage formation was found adjacent to the normal bone at week 1. The bone tissue was formed between the granules at week 2, while the amount of bone tissue increased and the lamellar bone formation was observed at week 4. The lamellar bone was increased at week 8. Histologic findings were Similar between the experimental groups 1 and 2, although the amount of Bioactive glass granules lost was increased in the latter. These results suggest that new bone formation is found around the Bioactive glass granules grafted into the bone defects, and the membrane plays a role in keeping the granules and preventing the fibrous tissue invasion.

• Journal of Periodontal and Implant Science
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• 제28권1호
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• pp.145-160
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• 1998

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue which has been lost due to destructive periodontal disease, and numerous kinds of materials and techniques have been developed to achieve this goal. Bone grafts include autografts, allografts, xenografts and synthetic grafts. Among the synthetic grafts, bioactive glass has been used in dentistry for more than ten years and Fetner reported improved new bone formation and more amount of new attachment after grafting PerioGlas, a kind of bioactive glass, in 2-wall defects of monkeys in 1994. It Is well known that 1-wall defects have less osteogenic potential and more epithelial migration, so we need to study the erect of bioactive glass in 1-wall dejects in dogs. The present study evaluates the effect of bioactive glass on the epithelial migration, alveolar bone regeneration, cementum formation and gingival connective tissue attachment in intrabony detects of dogs. Four millimeter deep and four millimeter wide 1-wall defects were surgically cheated in the mesial aspects of premolars. The test group received bioactive glass with a flap procedure and the control underwent flap procedure only. Histologic analysis after 8 weeks of healing revealed the following results: 1. The height of gingival margin was 1.30{\pm}0.73mm$ above CEJ in the control and $1.40{\pm}0.78mm$ in the test group. There was no statistically significant difference between the two group. 2. The length of epithelial growth (the distance from CEJ to the apical end of JE) was $1.74{\pm}0.47mm$ in the control and $1.12{\pm}0.36mm$ in the test group. These was a statistically significant difference between the two groups (P<0.01). 3. The length of new cementum was $2.06{\pm}0.73mm$ in the control and $2.62{\pm}0.37mm$ in the test group. There was no statistically significant difference between the two groups. 4. The length of new bone was $1.83{\pm}0.74mm$ in the control and $2.39{\pm}0.59mm$ in the test group. There was no statistically significant difference between the two groups. These results suggest that the use of bioactive glass 1-wall intrabony defects has significant effect on the prevention of junctional epithelium migration, but doesn't have any significant effect on new bone and new cementum formation.

• 한국세라믹학회지
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• 제36권10호
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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.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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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.

• 한국세라믹학회지
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• 제40권3호
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• pp.255-261
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• 2003

생체활성 유리를 알루미나 기판에 코팅하고 이를 유사 생체 용액에 반응시켰을 때 코팅 유리층 표면에 생성된 수산화 아파타이트 형성 거동 변화에 대하여 연구하였다. 알루미나에 코팅된 생체 활성 유리를 여러 온도에서 열처리하였을 때 다양한 종류의 결정상이 나타났으며, 특히 110$0^{\circ}C$에서 열처리하였을 때는 $\beta$-wollastonite와 apatite, 120$0^{\circ}C$에서 열처리하였을 때는 $\alpha$-wollastonite와 apatite가 생성되었다. 이들 시편을 tris-완충용액에 반응시켰을 때, $\alpha$-wollastonite 결정의 부식 속도가 $\beta$-wollastonite의 부식 속도보다 빨랐다. 그리고 이들 시편을 유사 생체 용액과 반응시켰을 때는 두 코팅층 표면에서 수산화 아파타이트가 형성되었는데, 그 형성 속도는 $\alpha$-wollastonite가 포함된 시편에서 더 빨랐다.

• Composites Research
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• 제14권4호
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• pp.15-26
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• 2001

Implant용 bioabsorbable 복합재료의 계면물성과 미세파괴분해 메카니즘을 micromechanical 시험법과 음향방출을 이용하여 평가하였다. Poly(ester-amide)와 bioactive 유리섬유의 인장 강도와 탄성률 그리고 연신율은 분해시간에 따라 점차적으로 감소하는 경향을 보인 반면, chitosan 섬유는 분해시간 내에서 거의 변화가 없었다. Dual matrix composite 시험법을 이용하여 측정된 bioactive 유리섬유와 poly(L-lactide) 사이의 계면전단강도는 chitosan이나 poly(ester-amide) 섬유의 경우 보다 큰 값을 보였다. 그리고 계면전단강도 감소는 bioactive 유리섬유 강화 poly(L-lactide) 복합재료에서 가장 빨랐으며, chitosan 섬유의 경우가 상대적으로 가장 느린 경향을 보였다. Poly(ester-amide) 섬유의 분해시간에 따른 음향방출 진폭과 에너지는 점차로 감소하였고, 음향방출 진폭의 분포 역시 점차 좁아짐을 보여주었다. Bioactive 유리섬유에서 인장파단에 의한 음향방출 진폭과 에너지는 압축파단의 경우 보다 크게 나타났으며, 또한, 인장 및 압축시험 모두에서 초기상태가 분해 후 보다 더 큰 값을 보였다. 본 연구에서 평가한 계면물성과 미세파괴분해 메카니즘은 생흡수성 복합재료의 성능을 조절할 수 있는 중요한 요소가 될 것이다.

• 세라미스트
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• 제21권3호
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• pp.216-232
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• 2018

The average life span is over 80 years of age, and various biomaterials have being studied. Many research institutes and companies around the world have been commercializing bioactive glass through R&D, however, there is not much research in Korea. Most bioactive glass is applied to bone regeneration in powder form due to its excellent bio-compatibility. Recently, new applications such as scaffolds for tissue engineering and nerve regeneration have been found in composite form. The global market size is not as large as US $ 556 million in 2019, but the growth rate is very high at a CAGR of 14.35 %. This field is waiting for the challenge of new researchers.