All Ceramic Crowns and Cements

Question 1

How to strengthen ceramics?

Answer 1

Increase crystalline content and increase thickness

Question 2

Increased crystalline content leads to?

Answer 2

Opacity

Question 3

Strength of different ceramic materials

Answer 3

Y-TZP > eMax(Lithium disilacate; LDS) > Empress (Leucite reinforced glass ceramic)

Question 4

Zirconia in dentistry (1990 vs 1999)

Answer 4

1990: ortho brackets, prefabed posts, implates
1999: technology available for crowns (ProCera)

Question 5

Mpa of translucent zirconia

Answer 5

850

Question 6

Difference in crown prep from zirconia to CVC?

Answer 6

No difference

Question 7

Crown fabrication techniques for zirconia

Answer 7

• Full contour ceramic with internal and external colorations
• Minimal cutback with porcelain veneer material
• High strength core with porcelain veneer material

Question 8

How eMax crowns are fabricated and how is it done here art the school?

Answer 8

Machined (wet milled) or Pressed (what we do at school)

Question 9

% shrinkage of zirconia

Answer 9

20%

Question 10

Adjustments of Zirconia

1. Material Removal
2. Materail Additions

Answer 10

1. Dialite Zr Kit
   * course-stone or fine diamond
   * green=medium, orage=fine
2. Low fusion porcelain to add contacts-both Zr and LDS

Question 11

Cementation of non-silica based ceramics

Answer 11

No silane treatment

*Phosphate ester based cement or RMGI cement

Question 12

Cementation of silica based ceremics

Answer 12

1. HF etch surface
2. Silanate
3. Resin based cements TE or SE

Question 13

What can dentists do to minimize potential for fracture?

Answer 13

1. Minimize surface flaws:
   * Polish after adjusting (LDS and Zr)
   * Etch internal surface (LDS) and clean internal surface (Zr)
   * Do not grind internal surface (LDS and Zr)
2. Minimize Stress:
   * Increase thickeness
   * anteriors