not necessarily....
if the bridge was cemented 20 years ago, there is a good chance that
it can be removed if it hasn't been recemented since. if it can be
removed, if the color change isn't significant, it is possible to
restain the porcelain, if the tooth needs to go darker. if it needs
to go lighter, you are in trouble. the porcelain can be stripped and
re applied but i'm not sure exactly what a dentist will charge for
that.
good luck
C
Dental labs find that if the restoration has been in the mouth for many
months or more, that when they heat the restoration to dry off any moisture,
all the porcelain "pops" off (or much of it). Doing anything to the
porcelain after it has been in the mouth for a long time generally means
stripping off all the porcelain and applying new. Lab fee for this is
almost the same as having a new restoration fabricated. To have the
porcelain re-done, the dentist has to send an opposing model and a pick-up
model with the restoration. The dentist may as well get the margins in the
impression and make a brand new one.

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> not necessarily....
>
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> C
Jack S - 01 May 2007 21:45 GMT
> Dental labs find that if the restoration has been in the mouth for many
> months or more, that when they heat the restoration to dry off any
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> model with the restoration. The dentist may as well get the margins in
> the impression and make a brand new one.
I misdescribed the situation.
The tooth I would like to change in color is actually a live tooth that the
permanent bride anchors to.
That probably makes it more dificult, right?
>> not necessarily....
>>
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>> good luck
>> C
Amatus Cremona - 02 May 2007 00:05 GMT
If the tooth is part of the bridge, and it has porcelain on it, my comments
are applicable.

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>> Dental labs find that if the restoration has been in the mouth for many
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>>> C