
redoing procedure..title
Dear Dr. Mady: I had a root canal done on one of my teeth about
30 years ago and now the tooth is infected. My dentist said it is because
my root canal was done by some old technique using some sort of silver
filler inside the roots. He wants to take that stuff out and redo the
procedure. Do you think this really necessary and can it even be done?
J.G. in Lakeshore
Dear J.G.: Silver points were commonly used in the past to fill
and seal the roots of the teeth during root canal therapy, especially
during the '50s and '60s. They were more popular as an obturating (root
filling) material as opposed to gutta purcha (a rubber-like material)
that is widely used today. They are composed of pure silver.
Their use has declined to a point where few dentists even use them
anymore. Virtually no dental schools in North America are teaching the
routine use of silver points in endodontic (root canal) treatment.
Many of the reasons for this decline in use are justified and some
are not. Most failures of silver points are usually associated with
leakage and corrosion. It is the inability of silver points to seal
irregularly shaped root canals that allows leakage of the tissue fluids
into the canal, thus harbouring bacteria and causing potential reinfections.
The contact of these fluids with the silver point may result in corrosion
and thus the release of products including silver carbonates and silver
sulfates. It is these culprits that can be extremely damaging to the
tissues around the root(s)of the tooth.
If and when silver point root canals fail, the best thing that your
dentist or endodontist (root canal specialist) can do is attempt re-treatment.
During this, the most challenging, but necessary dilemma is to retrieve
or remove the point from the root canal. The points cannot be extracted
unless they are accessible, so your dentist will have to take care in
the removal of surrounding fillings and restorations so that the head
of the point does not get severed in the process. If this occurs it
makes retrieval much more difficult and sometimes impossible. If your
dentist or specialist uses ultrasonic tools and/or enhanced magnification
and lighting, the chances of success are greater.
It sounds like this is the necessary procedure for you and it can be
done most of the time with minimal consequences. After the failing point(s)
are removed, your dentist will clean and flush the inside of the root(s)
and refill them usually with a rubber-like material called gutta purcha.
This material tends to seal the end of the root and the inside walls
very well due to its adaptability and capability of being heated and
melted. This, in conjunction with a good sealer, may get you better
service out of your tooth for a number of years to come, once the tooth
is properly restored.
This column is reprinted with the permission of the author and The Windsor
Star. "Ask the Dentist" is written by Windsor dentist (and ECDS member),
Dr. David Mady Jr.. The column appears the first Thursday of each month
in the Windsor Star. Readers with questions can write to "Ask The Dentist",
c/o The Windsor Star, 167 Ferry St., Windsor Ontario, N9A 4M5