Question:
Last week I posted a question about how to evaluate whether and when I
should get a crown for a tooth with a 7-week old root canal that still
had sensitivity to touch. Thanks to numerous helpful suggestions from
members of this forum I've reached the following point (also
cross-posted in the original thread).
I went for a second opinion visit Thursday. Dentist used a high-powered
microscope (displayed on a screen and printed out) to get a better look
at the problem tooth. It showed one area that had been patched
(amalgam) on the back surface of the tooth and a small hairline crack
on the side of the tooth. This dentist proposed putting in a gold
crown, but warned that it is not certain that the tooth will be saved
in the long run. He didn't see any evidence in the x-ray that there was
a hidden untreated root.
Now here's another problem. This dentist has an excellent reputation as
judged by a local consumer magazine and a report on dentists that other
dentists recommend. He seems top-notch to me as well. However he will
cost hundreds more than my regular dentist--who also seems OK, but not
with anything like this guy's reputation. And, I think this dentist
wants to use a porcelan crown.
Is there much of a difference in these treatments? Is the gold crown a
better approach with a tooth with one real and one minor crack? I know
you don't know these dentists, but, in general, what hints can you give
about making this sort of choice?
Answer:
Considering the questionable nature of the tooth, its long-term
survival has much more to do with the outcome of the root canal and the
presence and nature of any root fractures than what material the crown
is made out of. In my mouth, I would rather have a gold crown, but many
patients would opt for porcelain on purely cosmetic grounds. As a
practical matter, if you are going to make the effort to save this tooth
and can accept the questionable long-term prognosis, either one will be
equally effective.
I was told that the crown would help strengthen the tooth against
fracture and I was assuming that the more malleable gold crown would
somehow be more able to get into a better fit. Is that wrong?
You're not going to beat the fit of gold. However, porcelain crowns
are almost always bonded into place, so any pre-existing fracture will
tend to be supported by either. I am concerned though that if a
fracture extends to the level of the bone now, it will not have to
spread further to prevent healing of any infection. This is sometimes
very difficult to determine visually, and though a fracture can
sometimes be inferred by an x-ray, you don't know for sure until you
extract the tooth and examine the root.
This is sometimes a difficult decision--to crown a tooth that may be
lost anyway. I will sometimes grind a tooth to remove it totally from
the bite, or sometimes place a temporary plastic crown on the tooth to
allow healing. I generally will not proceed with the crown if there is
any pain, and certainly not if I have any sign on x-ray that there is a
problem with the root canal treatment.
Regarding the details of the tooth, there isn't evidence one way or the
other. The x-ray isn't clear about hidden or untreated roots. There is
no temperature sensitivity, if that's important. On the other hand, the
endodontist said the roots he worked on were dead, so maybe that
wouldn't be expected.
Similarly, neither the x-ray nor visual examination revealed the extent
of the crack. Since I have already lost the lower wisdom teeth I want
to treat this tooth even knowing that it may fail sooner or later.
Dr. Bornfeld's advice is excellent. There's a couple of things that can
be done to be sure you don't spend so much money on a tooth that could
be lost:
1. Have the temporary crown made. This is usually made of acrylic or
resin. If there is a crack that can be "fixed" with a crown, your
symptoms will disappear.
OR
2. Have an orthodontic band cemented on the tooth. This will have the
same effect on your cracked tooth symptoms as the temporary crown.
If after any one of these two alternatives your symptoms go away, then
have a permanent crown made. Either gold (all metal), porcelain (no
metal) or porcelain fused to metal can be done. Your dentist is in a
better position to say which is best in your case.
If the symptoms persist there may be a vertical fracture of one of the
roots and there may be no other alternatives but extraction.
