Elastomers Flashcards
What are the benefits of Alginate: Rapide 105
Speed set alginate - high levels of patient comfort are maintained due to speed of setting coupled with a pleasant taste.
Unique alginate polymer and excellent water solubility gives greater ease of mixing.
Enhanced thixotrophy gives greater accuracy of impression without excessive flow
Resultant high elasticity copes with the most severe undercuts.
The dimensional stability controlled by
pH balance in the formula limits syneresis of the final impression.
A perfect unblemished surface finishes off the cast model.
What depth of grooves must be replicated to meet the ISO standard for impression materials
20um or 50um depending on viscosity
What are the properties of Virtual
High tear strength
Superior elastic recovery
Accurate recording of surface detail
Excellent wettability
Good contrasting colours (caramel/blue)
Convenient to work with - flexible setting times
What is viscosity
- a measure of material’s ability to flow
- determines a material’s potential for making close contact with hard/soft tissue surfaces…….so how well it records surface detail
What is surface wetting
– impression material must make intimate contact with teeth/mucosa surfaces
– so all of surface is replicated
What is the ideal elasticity behaviour of an impression material
Complete 100% elastic recovery
No permanent strain
What reduces the amount of permanent strain
Removing the material quickly with a sharp pull
Is the ideal viscoelasticity high or low
Low viscoelasticity (small deformation)
Which are better impression materials - polyethers or addition silicones
The combination of the polymer and innovative spheroid silicon micro-fillers ensures exceptional precision and excellent reproduction of anatomical details
What are types of elastomers
Polyethers
Addition silicones
