table of contents

1. high strength ceramics2. solutions3. provisional 4. solutions

what are modern high strength ceramics?

– lithium disilicate (e.Max) – zirconia

“A factor critical to the strength and abrasiveness of ceramic materials is how the clinician adjusts, grinds, and polishes the ceramic restoration on delivery and cementation.” – John A. Sorensen, DMD, PhD, FACP

modern ceramics• “…there is no correlation between the

hardness of a ceramic and the potential abrasion of natural tooth structure.” – Sorensen

– microscopic surface roughness of the ceramic = abrasion

– finer the grain structure = lower the wear

– finer the grain structure = the more polishable

• zr/ld = Finest Grain Structure

zirconia~1200MPa

• pressed or milled • strongest • opaque• substructure or

monolithic

lithium disilicate~400MPa

• pressed, milled or layered

• second strongest • translucent• can be pressed within

2/10ths mm for anterior restorations (veneers)

zirconia~1200MPa

• BruxZir (Glidewell)• Lava Zirconia (3M ESPE)• Cercon (Dentsply)• In-Ceram (Vita)• Zirlux (Zahn)

lithium disilicate~400MPa

e.Max (Ivoclar Vivadent)

solutions

• occlusal – low RPM, low pressure

• 100K RPM

• anatomy

– low RPM, low Pressure• 100K RPM

solutionsheat = micro fractures heatless grinder for adjustment(Max 240°F)

solutions

– LD Grinders• pink medium recommended for Lithium Disilicate• Green Coarse recommended for Zirconia

– Dialite Diamonds– adjust/removal

– removal, provided copious amounts of water, 100K rpm and light, steady touch

ZR LD

provisional

Tips and techniques

tips & techniques

composite provsionalBisAcryil

• Protemp (3M ESPE)• Luxatemp (DMG-

America)• Venus (Heraeus)

acrylic provisonalmethayl/methacrylate

• Snap (Lang Dental)• Jet (Parkell)

problem: messy pumice + ragwheel

solution: 2-step polish – no rag wheel• minimal heat• no pastes or compounds needed

#1: medium pre polish #2 fine high

shine

other uses• Night guards• Splints• Flippers • Dentures• Orthodontic Retainers