Earticle

초록

영어

Purpose: This study analyzed the mechanical properties of dental zirconia blocks as a function of the size of artificially introduced initial cracks. Methods: Rectangular specimens (30×4×3 mm) were prepared, and cracks were introduced using a Vickers hardness tester under 0 (no applied load), 5, 20, and 30 kg loads. The crack lengths and indentations were measured microscopically, and the fracture toughness was calculated. Results: The Vickers hardness ranged from 1,414.9 to 1,515.5 kgf/mm2, and the fracture toughness ranged from 5.2 to 8.2 MPaㆍm1/2. The higher the load, the larger the cracks created. Further, the bending strength of zirconia decreased considerably as the cracks propagated. Uncracked specimens had a strength of 1,147~1,244 MPa, whereas cracked specimens with 5, 20, and 30 kg loads exhibited values of 237~290, 179~191, and 140~152 MPa, respectively. The fatigue life also reduced drastically with the crack appearance, falling to ≤1,060 cycles, compared with the over 1 million cycles observed for the intact specimens. Conclusion: Initial cracks considerably decreased the bending strength and fatigue life of zirconia. The size of the initial cracks increased with the indentation load, resulting in a decrease in the bending strength and fatigue life.

목차

Article Info
INTRODUCTION
MATERIALS AND METHODS
1. 시편 재료
2. 시편 제작
3. 실험 방법
RESULTS
1. 경도 및 파괴인성
2. 굽힘시험
3. 피로시험
DISCUSSION
CONCLUSIONS
FUNDING
ACKNOWLEDGEMENTS
CONFLICT OF INTEREST
ORCID
REFERENCES

키워드

저자

• 이항재 [ Hangjae Lee | 코엔디티 ] Corresponding Author
• 박중민 [ Jungmin Park | 엠펙 ]

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  대한치과기공학회지 [THE JOURNAL OF KOREAN ACADEMY OF DENTAL TECHNOLOGY]

• 간기

  계간

• pISSN

  1229-3954

• eISSN

  2288-5218

• 수록기간

  1979~2026

• 등재여부

  KCI 등재

• 십진분류

  KDC 515 DDC 617