Composite Flashcards
What are the different components of composite
Resin
Glass filler particles
Camphorquinone
Dimethacrylates
Silane coupling agent
What are the different types of glass filler particles
Conventional
Fine
Hybrid
Microfine
What resin is used in composite
Bis-GMA 0 which works by crosslinking via free rdical addition polymerisation
What does camphorquinone do
It is photo-intiator which produces radical molecules that intiate free radical addiation polymerisation of BIS-GMA and changes the resin properties
What is found in composite which adjusts the mechanical properties
Dimethacrylte
What allows intimate contact with the resin and glass filler particles in composite?
Silane coupling agent which provides a good bond
What property changes does the resin get from camphorquinone
Increased molecular weight, vicosity and strength
What are the different types of filler particles
Conventional
Hybrid
Macrofilled
What does increasing the filler size range and % volume of filler particles do?
Improves strength, rigidity,, hardness and abrasion resistance
Lower themeral expansion, polymerisation shrinkage
less heat
improves aethetics
Light curing?
uses a blue light and camphorquinone to produce free radicales which break the C=C bond and polymerisation occurs
Self curing?
uses benzoyl peroxide and aromatic tertiatry amine to produce free radicals and polymerisation occurs
What are the advantages of light curing composite
on demand setting
less finishing required
less waste
less porosity
higher filler level
What are the disadvantages of light curing composite
Occular damage
soft tissue damage
pulpal damage
short setting times
early polymerisation and shrinkage
What is the curing depth of light cured composite?
2mm as it prevents a soggy bottom
What is a soggy bottom
it is when the composite increment is >2mm which means a poor bonding occurs to the tooth surface
