Clinical Aspects of Resin Composites Flashcards
whats the basic chemistry of a GIC
Acid-base reaction between polyacrylic acid and glass fillers
whats the basic chemistry of a resin composite
made from Bis-GMA & UDMA
inorganic fillers
whats the basic chemistry of amalgam
alloy of silver, mercury & tin
what’re the 2 types of amalgam
spherical = more flowable
lathe-cut = less flowable, for building up large amounts of tooth structures
whats the unwanted product of amalgam
gamma2
what are some disadvantages with gamma2
- corrosion
- creep (changes shape under load
- decrease in strength
- tarnishing
what may reduce the effects of gamma2
addition of copper
what are the helpful aspects of gamma2
helps form seal between dentine and amalgam (prevent secondary caries)
how much of amalgam is mercury
around 50%
cons about amalgam use
- toxic vapor ingested
- released when chewing & brushing
- bad for environment
whats the difference between a resin modified GIC (Fuji II LC) and conventional GIC (Fugi XI)
Fuji II LC
- light cured
- improved handling
- abrasion resistance
Fugi XI
- chemically set
- F release
- low abrasion resistance
whats the name of the most common priming agent
HEMA
whats the name of the most common bonding agent
bis-GMA
what’re the advantages and disadvantages for GICs
Pros:
- tooth coloured
- bonds to enamel & dentine
- less moisture sensitive
Cons:
- poor wear resistance
- brittle
- opaque = aesthetics
