Once tooth enamel has been destroyed by acid, it will not be
replaced; neither will the dentin of the tooth when it has been destroyed. But
if the decay has not gone too far, the dentist can save the tooth by removing
the diseased portion and filling the cavity. For this, he drills out the
decayed area, applies an antiseptic, then inserts a well-fitted filling. When
decay has penetrated to the pulp and root canal, the tooth may ache.
The nerve
dies and infection spreads around the ends of the roots in the jawbone. This
may lead to infections elsewhere even when the tooth itself does not hurt.
The dentist tries to save most of the tooth by cleaning out
the decay and the residue of pulp and nerve. He sterilizes the root canals,
then fills them and the cavity to seal them and keep them sterile. Thereafter,
such a tooth is examined at intervals by x-ray. If the infection continues or
recurs, the tooth may have to be extracted, but there is a good chance that it
can remain in place.
Techniques of re-implanting dislodged teeth and of inducing
damaged tissue to regrow are new and still not matters of routine dental
practice, but they are advancing beyond the merely experimental stage. Re-implantation
means that, under some circumstances, a permanent tooth that has been knocked
out may be reinserted into its socket, reinforced, and encouraged to grow back
into the jaw. In regeneration, the tissues and bone around teeth, after being
destroyed by disease, may be induced to grow back.
