irs-t high strength ceramic restorations

Question 1

How are ceramics supported?

Answer 1

1. Resin bonded- tooth support
2. PFM- metal substructure support
3. High strength ceramic substructure support (CADCAM, traditionally- slip-casting, ceramic sintered)

Question 2

What are zirconia substructure materials?

Answer 2

Yttrium stabilised zirconia machined in their pre-sintered soft state

Milled 20% oversize to compensate for shrinkage during firing

Eg. Procera, Lava, infinident, Zircon Zahn, ZR

V OPAQUE- some translucent now available

- Alumina (Procera)- similar applications

Question 3

What are glass infiltrated substructure materials?

Answer 3

INCERAM- Spinell, Alumina, Zirconia
-substructure produced from blocks of lightly sintered material and once shaped- glass infiltrated

Question 4

What are indications for glass infill substructure materials?

Answer 4

Spinell- translucent, not as strong, single anterior units only

Alumina- fairly translucent, strong, single units and anterior bridges

Zirconia- v strong, bridge frameworks

Question 5

What are advantages of GI substructure materials?

Answer 5

Aesthetic
V strong
Simple to produce
Biocompatible
Trendy

Question 6

What are disadvantages of GI substructure materials?

Answer 6

Expensive
Confusing choice of materials and methods
Varying strengths and optical properties
Expensive