Lecture 5 Part 2: All Ceramic Crown

What are some differences between monolithic eMax and monolithic zirconia ?

- Monolithic e.Max (Milled):Is a Glass Ceramic, can be Etched/bonded with resin cement, need sslightly more reduction (> 1mm axial) -Monolithic Zirconia: Is a Polycrystalline Ceramic, can be cemented, Reduction similar to CVC. (0.5-0.65mm axial)

What three types of all ceramic crowns are utilized at our school

1. Layered Zirconia Crowns (PFZ) *BEST ESTHETIC • Coping: Milled Zirconia • Veneering Porcelain: A Glass Ceramic such as Feldspathic or Lithium Disilicate (e. Max) 2. Monolithic Zirconia Crowns • Milled Zirconia 3. Monolithic e.Max Crowns • Milled Lithium Disilicate

Most modern All Ceramic Crowns (Layered Zirconia, Monolithic Zirconia, Monolithic e.Max), the INTERNAL FITTING SURFACE is ____________

MILLED!

For layered zirconia crowns, the Coping is __________ Zirconia, the Veneering Porcelain is a Glass Ceramic which ould be pressed or hand stacked on top of the Zirconia Coping

Milled

when checking marginal internal fit, use the _______ _______ and if there needs to be adjustments make adjustments to the prep and not the crown and if it still does not fit rescan and remill

fit checker

Lithium Disilicate Crowns aka eMax crowns can be pressed using ________ over either metal or zirconia as veneering porcelain or milled using CAD CAM blocks resulting as a monolithic crown

ingots

the monolithic zirconia preparation is similr to CVC except for _________ ___________.

margin design

Monolythic crowns are made via mlling, pressed, or cast, except for zirconia which must be __________.

milled IN GREEN STATE (semi splintered) after milling is sintering

T/F Below are indication of monolithic zirconia: • Molars • Esthetics (buccal/Occlusal) • Lack of space for PFM porcelain occlusal • Bruxor patient DO NOT USE FOR ANTERIRO

true

the minimum thickness of coping for a PFM is 0.3 mm versus the layered zirconia is _____mm.

0.5 mm

impressions can be done via PVS or digital; however, if margins are subgingival ______________ impression is mandatory

PVS

What is zirconia?

Zirconia is a Polycrystalline Ceramic and NOT a Glass Ceramic; can't be etched, pressed, casted or hand stacked. it can only be MILLED

what is the margin design for zirconia crown>

do not bevel or use chamfer

t/f outline for ceramic crowns is the same, it follows CADET, 0.65mm Supragingival, > 0.5mm Separation with adjacent teeth, No damage of adjacent teet Retention for ceramic crowns is the same as well: • Ideal taper of 6-10 Degrees. (Same!!) • > 3mm 1st Plane • Avoid parallel walls or undercut which can confuse the scanner • No secondary retentive features marginal finsih for ceramic crowns is the same as well: • Shoulder with Rounded Internal • 90 degrees to external tooth surface • Clear, Continuous, Smooth and Free of Irregularities • Terminate on Sound Tooth Structure • Well Supported

true

what is the internal reduction for Layered Zirconia, Monolithic Zirconia, Monolithic e.Max

• Layered Zirconia: Min 1.0 mm Gingival Axial Reduction All Around • Milled e. Max: Similar to Layered Zirconia • Monolithic Zirconia: Similar to CVC

Describe the preparation of a monolithic zirconia

• Occlusal & Gingival Axial reduction: similar to CVC --> Occlusal: 1.5 mm (1-1.75 mm) --> Gingival axial: 0.65 mm (0.5- 1.0 mm) • Slight more rounded occlusal line angles