LECTURE 9: DIRECT GOLD RESTORATIOn Flashcards
DIRECT GOLD
two types for dental use:
o gold foil
o powdered gold
→ superior restorative material
→ can last a lifetime
→ superb biocompatibility with oral environmen
DIRECT GOLD
T/f
Direct gold has an excellent marginal integrity
T
T/f
DIRECT GOLD INDICATIONS:
teeth abraded, eroded or has abfraction on facial surfaces of
teeth
T
INDICATIONS:
All classes with small cavitated tooth EXCEPT class IV
DIRECT GOLD
T/f
DIRECT GOLD is contraindicated with root canal filled teeth, handicapped patients unable to sit for a long appointment
T
T/f
DIRECT GOLD is contraindicated for teeth with very large pulp chambers, severe periodontally weakened teeth, economics
T
T/f
gold foil is manufactured by beating pure gold into thin sheets
T
the 4x4 inch sheets of gold foil are too large to use in restorative procedures that is why it is rolled into ______ or ___ before insertion
into tooth preparations
cylinders, pellets
GOLD FOIL pellets are rolled from:
o 1/32 inch
o 1/43 inch
o 1/ ___inch or
o 1/128 inch
64
damp cotton pellet with ________ into each box section to prevent deleterious oxides from forming on gold
18% ammonia
combination of chemical precipitation and atomization, with an average particle size of 15 mm
A. GOLD FOIL
B. POWDERED GOLD
B
marketed as Williams E-Z Gold
A. GOLD FOIL
B. POWDERED GOLD
B
atomized particles are mixed together in wax, cut into pieces, and wrapped in no. 4 or no. 3 foil
A. GOLD FOIL
B. POWDERED GOLD
B
T/f
the gold must be in a cohesive state before compaction
T
gases must be removed from the surface of the gold before dental compaction accomplished by heat application; desired result is to remove residual surface contamination
degassing/annealing
accomplished by heating the gold foil on a mica tray over a flame or on an electric annealer or by heating each piece of gold over a pure 2. _____ flame
- degassing/annealing
- ethanol
T/f
all direct-filling gold products are degassed immediately before use
T
gold is passed into the blue inner core of the flame on the tip of a foil passing instrument and held just until the gold becomes dull ____; then the instrument is withdrawn from the flame–after a few seconds are allowed for cooling, the gold is placed in the preparation
red
preferred technique:
o___ to deliver light blows to a condenser held by the dentist → allows great control of malleting forces and allows for rapid change in condenser nibs, or tips, when a multitude of condensers is required
hand mallet