Exam 2: Dental Cements Flashcards
What are the types of cements?
- ZINC PHOSPHATE
- ZINC OXIDE EUGENOL
- ZINC POLYCARBOXYLATE
- GLASS IONOMER
- RESIN-MODIFIED GLASS IONOMER
- PROVISIONAL CEMENTS
It is important to note that no cement will perform to it’s optimal level clinically without an _____________
ADEQUATE PREPARATION
What are the important characteristics to consider about cements?
BIOCOMPATIBILITY
RETENTION
MECHANICAL PROPERTIES
MARGINAL SEAL
LOW FILM THICKNESS
EASE OF USE
RADIOPACITY
ESTHETICS
What are the important mechanical properties of cements?
withstand occlusal forces, high tensile strength
The first cement in dental literature was…
zinc phosphate
Which cement is the gold standard?
zinc phosphate
What are the advantages of zinc phosphate?
- thin film thickness
- proven reliability
- low solubility (resists breakdown in mouth)
- low thermo-conductivity (less sensitivity)
- long shelf life
What are the disadvantages of zinc phosphate?
- initial low pH (pulpal irritation)
- no chemical adhesion/bond
- no antibacterial properties
- poor esthetics (for all porcelain)
- long setting time (2.5-8 minutes)
- exothermic (chilled glass slab when mixing)
What is the setting time for zinc phosphate?
2.5-8 minutes
How do you overcome the exothermic properties of zinc phosphate?
- mix on a chilled slab
- small amounts of powder added to liquid
What are the two types of zinc oxide eugenol (ZOE) cement?
Type 1: Temp-bond
Type 2: IRM
What are the properties of type 1 zinc oxide eugenol cement?
- less strong
- used for temporary restorations and for temporary cementation
What are the properties of type 2 zinc oxide eugenol cement?
- reinforced and stronger
- intermediate restorative
- lasts 6-12 months in the mouth
What are the benefits of zinc oxide eugenol cement?
- neutral pH
- sedative or soothing effect on the dental pulp
- protective/insulating base or liner is not required
What can you not use zinc oxide eugenol cement under?
not used under composite or acrylic restorations becuase eugenol is incompatible with these materials (retards the setting process)
What is the mixing time of zinc oxide eugenol cement?
30-60 seconds
What is the setting time of zinc oxide eugenol cement?
3-5 minutes
What is the first cementing system to obtain an adhesive agent that bonds to enamel and dentin?
zinc polycarboxylate
What are the advantages of zinc polycarboxylate?
- bonds to enamel and dentin
- antibacterial action
- shorter working time (2.5 min)
- not as fragile as zinc phosphate
What are the disadvantages of zinc polycarboxylate?
- poor marginal sealing due to film thickness
- doesn’t always support occlusal stress well
- does not bond to gold
- difficult to remove excess cement (rubbery)
- has to be mixed fast (30-40 sec)
- not used as often
What is the working time of zinc polycarboxylate?
2.5 minutes
What is the mixing time of zinc polycarboxylate?
30-40 seconds
What is important about dental materials?
bitches are expensive
don’t waste the shit
love the earth (unlike dom)
What are glass ionomers also known as?
acid-base cement
