Physical Properties of Porcelain

Question 1

Anterior laminates, anterior crowns, and anterior Bridges to 2nd PM should have what porcelain?

Answer 1

IPS e.max (Type B porcelain)

Question 2

What is the composition of Leucite Reinforced Core?

Answer 2

Glass matrix + 35% KAlSi2O6 Leucite crystals

Question 3

What is the composition of Feldspar porcelain?

Answer 3

Na/K/Al, Si oxides make a glass matrix that is added to 6-21% KAlSi2O6 Leucite crystals

Question 4

What porcelain type is indicated for posterior crowns in a patient with bruxism?

Answer 4

Type A BruxZir

Question 5

What is done to the inside of the Type B porcelain before cementation?

Answer 5

Etch w/ HF acid and treat with Silane to bind to dentin

Question 6

You should cement Type B porcelain w/ only what cement type and method?

Answer 6

Dual cure or self cure resin cements with dentin bonding agent and self cure activator (bond Link)

Question 7

What is the core in Type B Porcelains ?

Answer 7

Lithium di-silicate

Question 8

What are the cores in Type A porcelains?

Answer 8

Aluminum oxide or Zirconium oxide

Question 9

What cement is usable with Type A porcelains?

Answer 9

Self-adhesive resin, compomer, or RMGI

Question 10

Why can you not use VLC cements with Type A porcelains?

Answer 10

Type A porcelain is too opaque

Question 11

Why can you not use Zinc Phosphate cements with Type A porcelains?

Answer 11

Type A porcelain would be too soluble with such cements

Question 12

Why can you not use Glass ionomer cements with Type A porcelains

Answer 12

An acidic reaction would result

Question 13

Do not use what cements with Type A porcelains?

Answer 13

No Glass ionomer, Zinc phosphates, or VLC cements

Question 14

How are Type A Porcelains (all ceramic crowns with CAD/CAM cores) characterized with regards to strength and esthetics?

Answer 14

1. High strength

2. Lower esthetics

Question 15

For a PFM, what is the thickness of the metal coping with feldspar?

Answer 15

0. 3-0.5 mm in the veneered area

1. 0 mm in the unveneered area

Question 16

What is the coefficient of thermal expansion for Ney Option high Pd for Feldspar porcelain?

Answer 16

14.4x10-6 cm/K

Question 17

What metals are used in the Feldspar porcelain coping and what must its thermal expansion be in relation to porcelain?

Answer 17

78% Pd, 8% Cu, 2% Au

The coefficient of thermal expansion of metal and porcelain must match

Question 18

List the Type A porcelains.

Answer 18

1. Aluminum oxide core (Procera)
2. Zirconium Oxide core + veneer porcelain
3. All zirconium oxide

Question 19

List the Type B porcelains.

Answer 19

1. Leucite reinforced lithium dicilicate

2. Lithium disilicate

Question 20

What porcelain is used at VCU for PFMs?

Answer 20

Feldspar