Dental Materials F9
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DENTAL MATERIALS F9
•
SPHEROIDAL/SPERICAL ALLOY
AMALGAM
o
Medium
•
Most successful restorative material
•
Grayish-black colored restoration
o
Smallest
•
Cannot be used in the facial surface of anterior teeth for aesthetic reasons
o
Best used
o
Advantages:
•
CLASS I, II, V (posterior teeth; lingual/palatal of anterior teeth; buccal pits)
Uses minimal liquid (Hg)
•
Core build-up material
More compact filling
•
CLASS III (distal of cuspid not seen clinically)
Less void in between
•
56% causes of failure due to faulty…
Makes stronger set
•
40% causes of failure due to improper handling of the material
Smoother surface finish
Resist tarnish and corrosion
o
o
o
May be controlled by both the manufacturer and dentist MANUFACTURER
•
MERCURY •
Purity (should be pure with a mirror-like appearance)
Particle size
•
Certified pure by USP (US PHARMATECOPEA)
Component alloy
•
Toxic in pure state
Selection of alloy and mercury
DENTIST
o
Inhalation of Hg vapor
o
Entry through pores in skin
Selection of alloy and mercury
•
When mixed with alloy, toxicity disappears
Proportioning of alloy and mercury
•
When an amalgam restoration is subjected to 80°C, the free form of Hg will rise to the surface
Trituration process •
Condensation process
Handpieces should have water to serve as coolant when manipulating amalgam
Burnishing
Carving
Finishing/polishing of amalgam
SELECTION OF ALLOY AND MERCURY •
ALLOY •
Combination of different metals
•
Dispensed in:
•
SILVER (Ag) o
65 – 75%
o
For strength of amalgam restoration
o
Too much will lead to expansion
TIN (Sn)
o
POWDER/FILING
o
25 – 27%
o
PELLET/TABLET
o
Too much will lead to shrinkage
•
DISPERSED/FINE CUT ALLOY
Powder placed in PHARMACEUTICAL PILL MILL
•
COPPER (Cu) o
6%
o
For strength of amalgam restoration
LATHE-CUT ALLOY o
Big particle sized •
ZINC (Zn)
o
1 – 2%
o
Too much will deoxidize amalgam restoration
•
Grainy is under triturated
will make the restoration not undergo discoloration
•
A little shiny
o
o
o
zinc + moisture (premature contact) leads to secondary/delayed expansion
o
PROPORTIONING OF ALLOY AND MERCURY
•
always more mercury than alloy
•
6:5
•
o
Manually proportioned
o
Fine cut
o
Can be 8:6
1:1 o
•
Remove surface coating of alloy so that it will be easily mixed with mercury
•
Reduces size of alloy
•
Provide proper union between alloy and mercury
•
Methods of Trituration: o
Uses MORTAR & PESTLE
Hold pestle in a PALM & THUMB GRASP manner to apply pressure
Mortar has slightly raised center to guide the trituration against the walls in one direction
Should be dine in hard, flat surface
45 – 60sec mixing time
Must look: •
Smooth
o
Should not cling at the sides of mortar
•
Should easily curl down at the sides of the mortar
•
it will cling when there is too much Hg
•
over trituration makes the mixture cling to the sides of mortar
rub on skin to make mixture homogenous (or make it into ropelike without breaking it at any certain length)
when it breaks, it means it is dry (there is too much alloy)
too much Hg makes it heavy; cannot make it rope-like
too much mercury makes it flat
too much alloy makes it round
correct consistency makes it spherical
HAND TECHNIQUE
•
transfer to rubber dam sheath to do kneading and malling technique (continuation process of trituration…)
TRITURATION PROCESS
Mixing of alloy and mercury
Due to little/excess Hg at the start of mix
Machine-proportioned in a capsule with fine alloy
•
Particles must be properly mixed
MECHANICAL
Pre-mixed
Follow steps in instruction guide
Has plastic piston inside to serve as pestle
Advantages:
•
Shorter mixing time
•
Shorter setting time due to heat release
Disadvantages:
•
Eliminates…
-Rosette Go 031409
•
SPHEROIDAL/SPERICAL ALLOY
AMALGAM
o
Medium
•
Most successful restorative material
•
Grayish-black colored restoration
o
Smallest
•
Cannot be used in the facial surface of anterior teeth for aesthetic reasons
o
Best used
o
Advantages:
•
CLASS I, II, V (posterior teeth; lingual/palatal of anterior teeth; buccal pits)
Uses minimal liquid (Hg)
•
Core build-up material
More compact filling
•
CLASS III (distal of cuspid not seen clinically)
Less void in between
•
56% causes of failure due to faulty…
Makes stronger set
•
40% causes of failure due to improper handling of the material
Smoother surface finish
Resist tarnish and corrosion
o
o
o
May be controlled by both the manufacturer and dentist MANUFACTURER
•
MERCURY •
Purity (should be pure with a mirror-like appearance)
Particle size
•
Certified pure by USP (US PHARMATECOPEA)
Component alloy
•
Toxic in pure state
Selection of alloy and mercury
DENTIST
o
Inhalation of Hg vapor
o
Entry through pores in skin
Selection of alloy and mercury
•
When mixed with alloy, toxicity disappears
Proportioning of alloy and mercury
•
When an amalgam restoration is subjected to 80°C, the free form of Hg will rise to the surface
Trituration process •
Condensation process
Handpieces should have water to serve as coolant when manipulating amalgam
Burnishing
Carving
Finishing/polishing of amalgam
SELECTION OF ALLOY AND MERCURY •
ALLOY •
Combination of different metals
•
Dispensed in:
•
SILVER (Ag) o
65 – 75%
o
For strength of amalgam restoration
o
Too much will lead to expansion
TIN (Sn)
o
POWDER/FILING
o
25 – 27%
o
PELLET/TABLET
o
Too much will lead to shrinkage
•
DISPERSED/FINE CUT ALLOY
Powder placed in PHARMACEUTICAL PILL MILL
•
COPPER (Cu) o
6%
o
For strength of amalgam restoration
LATHE-CUT ALLOY o
Big particle sized •
ZINC (Zn)
o
1 – 2%
o
Too much will deoxidize amalgam restoration
•
Grainy is under triturated
will make the restoration not undergo discoloration
•
A little shiny
o
o
o
zinc + moisture (premature contact) leads to secondary/delayed expansion
o
PROPORTIONING OF ALLOY AND MERCURY
•
always more mercury than alloy
•
6:5
•
o
Manually proportioned
o
Fine cut
o
Can be 8:6
1:1 o
•
Remove surface coating of alloy so that it will be easily mixed with mercury
•
Reduces size of alloy
•
Provide proper union between alloy and mercury
•
Methods of Trituration: o
Uses MORTAR & PESTLE
Hold pestle in a PALM & THUMB GRASP manner to apply pressure
Mortar has slightly raised center to guide the trituration against the walls in one direction
Should be dine in hard, flat surface
45 – 60sec mixing time
Must look: •
Smooth
o
Should not cling at the sides of mortar
•
Should easily curl down at the sides of the mortar
•
it will cling when there is too much Hg
•
over trituration makes the mixture cling to the sides of mortar
rub on skin to make mixture homogenous (or make it into ropelike without breaking it at any certain length)
when it breaks, it means it is dry (there is too much alloy)
too much Hg makes it heavy; cannot make it rope-like
too much mercury makes it flat
too much alloy makes it round
correct consistency makes it spherical
HAND TECHNIQUE
•
transfer to rubber dam sheath to do kneading and malling technique (continuation process of trituration…)
TRITURATION PROCESS
Mixing of alloy and mercury
Due to little/excess Hg at the start of mix
Machine-proportioned in a capsule with fine alloy
•
Particles must be properly mixed
MECHANICAL
Pre-mixed
Follow steps in instruction guide
Has plastic piston inside to serve as pestle
Advantages:
•
Shorter mixing time
•
Shorter setting time due to heat release
Disadvantages:
•
Eliminates…
-Rosette Go 031409
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