Page 35 - Amazing Smiles

figure 32 Cosmetic Dental Procedures
figure 33
layer is applied over the metal. This results in a
crown with the appearance of an opaque-like or
dead look. This effect can be lessened by using a
high carat alloy gold inside the crown instead of a
new gold containing silver looking metal. Careful
staining by a very talented dental technician can
sometimes overcome this opaque look to make
the crown look more natural. However, this is not
an easy task and it truly involves a great deal of
talent and experience.

Another problem associated with porcelain
fused to metal crowns is the black line phenomenon.
(figure 32).

The black line appears because the porce-
lain fused to metal crown must end at or below
the gum line with an all-metal margin. Dentists
usually try to hide this black line by preparing the
tooth deep enough below the gum line so that the
metal margin does not show. However, many
patient’s gums are thin and translucent and the
dark line shows through. Some have gum reces-
sion over time, exposing the black line of the
metal margin, which originally did not show. The
“black line” phenomenon is eliminated when
using a “all porcelain crown.” (figure 33).

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