치과용 지르코니아의 소결 및 전장도재와의 결합 특성 = Sintering and Bonding Properties of Dental Zirconia with Veneering Ceramics

다국어 초록 (Multilingual Abstract)

Densification and mechanical properties of dental zirconia ceramics were evaluated by different sintering methods. Microwave sintering was very effective so that considerable mechanical properties such as flexural strength and bulk density were drastically increased than conventional electric heating
method. It is also shown that microwave sintering time was faster and more economical than common method to be present in qualities which equal or exceed. However, in the high heating rate, some cracks were occurred in the thick specimens. By adjusting the heating rate in dry phase at lower temperature
than 400℃, thereby having been able to inhibit the crack formation, which had occurred in the specimen with large thickness due to moisture, and to obtain the fine zirconia sintered body. However, it will be important to seek the accurate sintering condition of dental zirconia by microwave sintering method and the continuous research is necessary for the study of relationship between sintering temperature and mechanical properties.
The shear bond strength between sintered zirconia cores and veneering ceramics was measured and the effect of Coefficient of Thermal Expansion(CTE) of veneering ceramics and surface treatment method were evaluated. Four groups of veneering
ceramics with different CTE were sintered on sandblasted zirconia. The shear bond strength of lower CTE was higher than high CTE groups. And 4 groups of specimens with different surface treatment were prepared. Group I: without any
pre-treatment, Group II: treated with sandblasting, Group III: treated with liner, Group IV: treated with sandblasting and liner. The shear bond strength was tested in a universal testing machine. The shear bond strength of Group II was significantly higher than the other groups. Sandblasting decreased the
percentage of interfacial failure patterns and increased the surface roughness and bond strength. In contrary, liner application reduced the shear bond strength and increased the likelihood of interfacial failure and delamination of the veneering ceramic from the zirconia core structures. CTE of the core and veneer is an important factor in making a successful core veneer combination. Finally the effect of thermo-cycling treatment on the bond strength and flexural strength of ceramic veneered zirconia was evaluated. After thermo-cycling treatment between 5℃ to 55℃ ceramic-zirconia bond strength and zirconia flexural strength was not affected. In the phase analyses using XRD, after thermo-cycling treatment, however both the experimental group and the control group were tetragonal phase. That is, the ceramic-zirconia bond strength and zirconia flexural strength were unaffected by low temperature degradation. So low temperature aging treatment did not reduce the flexural strength and the temperature applied to the aging treatment was relatively low.

목차 (Table of Contents)

• 제 1 장 서 론 1
• 제 2 장 이론적 배경 7
• 2-1. 치과 보철 7
• 2-2. 치과용 세라믹 10
• 2-3. 치과용 지르코니아 15
• 2-4. 치과용 지르코니아 세라믹의 제작과정 19
• 2-5. 지르코니아의 마이크로웨이브 소결 27
• 2-6. 비니어링 세라믹의 열팽창계수 35
• 2-7. 지르코니아의 저온열화 39
• 제 3 장 소결방법에 따른 치과용 지르코니아의 물리적 특성 43
• 3-1. 서 론 43
• 3-2. 연구 재료 및 방법 45
• 3-2-1. 연구 재료 45
• 3-2-2. 시편의 소결 45
• 3-2-3. 밀도측정 48
• 3-2-4. 3점 굴곡강도 시험 49
• 3-2-5. 미세구조 관찰 50
• 3-3. 결 과 51
• 3-3-1. 소결 방법에 따른 소결시간의 차이 51
• 3-3-2. 소결 조건에 따른 밀도 변화 54
• 3-3-3. 시편 두께에 따른 밀도 변화 55
• 3-3-4. 초기 승온속도 변화에 따른 파절양상 및 밀도변화 58
• 3-3-5. 소결방법에 따른 굴곡강도 59
• 3-3-6. 미세구조 관찰 60
• 3-4. 고 찰 63
• 3-5. 결 론 67
• 제 4 장 비니어링 세라믹의 전단결합강도 69
• 4-1. 서 론 69
• 4-2. 연구 재료 및 방법 71
• 4-2-1. 연구 재료 71
• 4-2-2. 지르코니아 시편의 제작 73
• 4-2-3. 지르코니아 표면처리 및 관찰 73
• 4-2-4. 도재축성 및 소성 74
• 4-2-5. 시편의 고정 75
• 4-2-6. 전단결합강도의 측정 75
• 4-2-7. 파절면 분류 및 관찰 76
• 4-3. 결 과 77
• 4-3-1. 표면처리방법에 따른 표면거칠기와 형태 77
• 4-3-2. 표면처리방법에 따른 비니어링 세라믹의 결합강도 79
• 4-3-3. 열팽창계수 차이에 의한 비니어링 세라믹의 결합강도 80
• 4-3-4. 파절면 분석 82
• 4-4. 고 찰 86
• 4-5. 결 론 89
• 제 5 장 수분환경이 지르코니아와 비니어링 세라믹에 미치는 영향 90
• 5-1. 서 론 90
• 5-2. 연구 재료 및 방법 93
• 5-2-1. 연구 재료 93
• 5-2-2. 지르코니아 시편의 제작 94
• 5-2-3. 비니어링 세라믹의 축성 및 소성 94
• 5-2-4. 시편의 열수처리 95
• 5-2-5. 3점 굴곡강도 시험 96
• 5-2-6. 상분석 97
• 5-2-7. 미세구조 관찰 98
• 5-3. 결 과 99
• 5-3-1. 열순환 처리에 따른 비니어링 세라믹의 결합강도 99
• 5-3-2. 열순환 처리에 따른 지르코니아 세라믹의 굴곡강도 100
• 5-3-3. 열순환 처리에 따른 상변화 101
• 5-3-4. 미세구조 관찰 103
• 5-4. 고 찰 104
• 5-5. 결 론 106
• 제 6 장 종합 결론 107
• References 109