PMMA (acrylic resin) Flashcards
1
Q
give some ideal properties of acrylic resin?
A
high softening temp unaffected by oral fluids high youngs modulus thermal expansion math that of tooth high thermal conductivity
2
Q
what does the liquid component of PMMA contains?
A
methacrylate monomer (dissolve pmma particles) inhibitor (hydroquinone) co-polymer (improve mechanical properties)
3
Q
what does the powder component of PMMA contain?
A
imitator (benzoyl peroxide) pmma particles plasticiser pigment co - polmymer
4
Q
what happens if u heat cure the PMMA above 100 degrees celsius?
A
gasses will be produced leading to porosity and a weaker denture
5
Q
what effects will under curing have on PMMA denture?
A
free monomer (irritant) low molecular weight (poor mechanical properties)
6
Q
too much monomer when making PMMA results in what?
A
contraction porosity
7
Q
too little monomer when making PMMA results in?
A
granularity
8
Q
name the 2 types of porosity u might get in acrylic?
A
gaseous porosity or contraction porosity
9
Q
name the good properties of PMMA
A
non toxic non irritant unaffected by oral fluids thermal expansion = artificial tooth high thermal conductivity low density
