Chapter 10 Materials for fixed indirect restoration Flashcards
1.
What is indirect fixed Restoration?
- constructed **outside **of the mouth
- Not meant to be removed
- Restores part of a tooth
How are indirect fixed resotrations classified?
- By the amount of tooth restored and material used to restore the tooth
What are some types of IFR?
indirect fixed restorations?
Bridge
Veneers
Inlay
Onlay
Crown
What are inlays?
- intracoronal (INSIDE the crown)
- Class I- pits fissure and grooves
- Class II- proximal surfaces posterior
- DONOT restore Cusps
- used luting cement and bonding resins
What are onlays?
- Restores one or more CUSPS
- (ON a cusp)
- Protects from occlusal forces
What is a veneer?
- Thin layer of material
- placed facially
- direct or indirect
- supported by underlying tooth structures
When are crowns needed?
- When there is significant tooth loss structure or fractures
What is a cantilever bridge ?
When a pontic only supported on one side
What are the indirect restorative materials ?
- metals
- ceramics
- ceramometals
- composites
What are the indirect restortative METALS?
- Noble metals: Gold, palladium, plantium and silver
High Noble is?
Greater than or equal to 60 %
Gold= 40% or more
Noble?
Noble greater or = to 25% with or without gold
Base metals
noble: less than 25%
What are the requirements for dental alloys?
- biocompatible
- Adequate physical and mechanical properties
- Corrosion resistant
- relative ease of favrication by trained dental personnel
- inexpensive
What are the steps for casting dental alloys?
- create wax pattern
- attach sprue
- invest the wax pattern
- burn out wax pattern
- cast the metal
- cool and retrieve
- finish and polish
what are indirect restorative ceramics?
- feldspathic
- leucite-reinforced
- lithium disilicate
- polycrystalline- zirconia
- hybrid resin ceramic
- porecelain fused metal- PFM
What is feldspathic?
- mixture of silica, feldspar, alumina
- highly esthetic
- more prone to fractures
- veeners
What is leucite-reinforced?
- added high amount of leucite crystals to feldspathic porcelain for strength
- veneers
What is lithium disilicate ceramic?
- composed of lithium disilicate crystals and glass matrix
- strong and suitable for veneers, crowns and bridges
What is zirconia?
- zirconium dioxide
- extremely strong
- opaque
- less wear on enamle
- difficult to bond
- crowns, bridges
What are hybrid resins?
- blend of ceramic and resin
- combines benfits of ceramics and flexibility of resin
- easier to adjust and polish
- uncertain clinical longevity
What are porcelain fused to metal?
- Metal substructure with porcelain overlay
- Can show darkline at gingva
- Wised for many years
- Crowns and bridges
