Advantages of Piece method of annealing
No wastage
Choice of selecting correct size
The eliminations of chance of contamination of gold foil between annealing and use

Disadvantage:
Need of assistant

BULK METHOD OF ANNEALING

Mica tray is attached to alcohol lamp
Many gold pellets can be heated together
ELECTRIC ANNEALING:
The desired gold is placed in the divided trays of annealer and lid is closed
Gold is heated for 10 minutes at 850 F (3500C)
Then it is allowed to cool momentarily
Advantages: No need of assistant
It is time savings
DISADVANTAGES:
Wastage by heating extra pellets
Inability to select proper size which fits into cavity
Danger of over annealing
Convection air currents can also cause inadequate heating of the tray and results in poor welding properties
CAVITY PREPARATION FOR DFGs:
Principles are same and as for amalgam
Differences are evident in the design features and instrumentation related to retention, convenience and enamel wall finishing

Retention point by 33 ½ inverted cone bur or by angle former (61/2 – 90 – 21/2 – 9) or ¼ round bur or (6 ½ – 2 ½ – 9) hoe
Retention point is for starting of placing gold foil which is convenience form.
Enamel wall is bevelled 450 for encapsulating the final DFG for prevention of microleakage
CONDENSATION OF GOLD FOIL (DFG) OR COMPACTION OF GOLD FOIL
The aims of condensation of cohesive gold are
Weld together the pieces of DFG
To adapt the gold to walls of the cavity and margin closely
To gain an uniform compactness and drive out all air between the pieces of gold
To cold work and harden the mass
Develop strength within the restoration
Instruments commonly used for condensation
The Black
Wood bury
Ferrier
Lomalinda
Types of condensation:
Hand condenser and mallet
Automatic condenser
Hand Condensation:
Disadvantages: Force is not uniform therefore frequency of blow is not uniform therefore chances of fracture of tooth at cavosurface
AUTOMATIC CONDENSER:
Hollen Back pneumatic condenser electro mallet
Both will have straight and contra-angled H.P with rubber cups of different size frequency range is 3600 vibrations.
Advantages:
Force of blow is regular
No chance of tooth fracture
Manual variations are less

The difference of gold foil condensers from other instruments are that –
Longer handles
Flattened ends for malleting
Straight shaft to help the dentists to direct the line of force
NIBS: Serration on the ribs
Serrations are small and pyramidal in shape (Increased surface area of working point)
They serve to interlock each pellet with previously placed gold
Creates cohesion
Condensation procedures:
Pressure 15lbs/inch 2 of force on the condenser is needed. Smaller the condenser better cohesion
Line of force: Is directed 450 to cavity walls
Line of force should be directed in such way to bisect line angles and trisect point angles after sitting of gold foil in the cavity.
Employ uniform stepping condenser. Each succeeding step of nib overlaps the previous one by at least 1/4th of the nib face diameter
Wedging of gold foil should be achieved for proper strength and compactness bridging should be avoid totally
6. To reduce the placement time, powdered or platinised gold is used for core and cohesive gold foil is used to veneer the surface of restoration
FINISHING AND POLISHING:
Contouring the filled restoration
Spartely burnisher
Moone Scaler
Jones knife
Spartely burnisher is helpful in marginating gold foil. Inter proximal finishing is done by strips made of linen. Plastic coated with abrasives
Final polish is due for class I, II, pits and class V silica and pumice are used for smoothening.
Metallic oxides (like tinoxide or rouge) are used for final polish to get luster of gold.
Polish reduces tarnish and corrosion,
Promotes health of gingiva and
Enhances qualities of pure gold