Dental ceramics Flashcards
1
Q
composition of dental ceramics
A
- Feldspar
- borax
- silica
- metallic oxides
2
Q
How do dental ceramics differ from conventional?
A
- Kaolin removed
- replaced by feldspar and silica
- as dental ceramics need to be translucent
3
Q
advantages of conventional dental ceramics
A
- good aesthetics
- chemically stable
- good biocompatibility
- similar thermal properties to tooth surface
- good dimensional stability
- high hardness
- high compressive strength
4
Q
disadvantages of conventional dental ceramics
A
low tensile strength
low flexural strength
low fracture toughness
can form surface micro-cracks
5
Q
Why are conventional dental ceramics only used for anterior crowns?
A
too brittle to be used elsewhere
6
Q
disadvantages of zirconia cored crowns
A
- expensive equipment required
- potential for veneering porcelain to debond from core
- zirconia core is opaque
- inert fitting surface, cannot etch or bond
