What is root canal treatment?
If tooth decay is left without being fixed by a dentist, it will grow bigger and deeper into the tooth, causing holes (cavities) A large hole, which grows close to the pulp of the tooth, can result in infections in the root canal(s) of your teeth.
This is because bacteria can more easily enter into the pulp through the hole in the tooth. The bacteria can then make its way down to the root canal(s) and will develop an abscess (the yellowish patch under the left root of the tooth in the below diagram).
The abscess, which is full of pus, will push against the bone surrounding the tooth. It can't escape as there is nowhere for it to go, this can cause a lot of pain!
The only way to get the pus out is to have root canal treatment, or get the
pulled out. Root canal treatment clears all the pus and
bacteria out of the canal, then a crown is put on top of the
tooth to cover the hole and prevent further infections. However, it is not
always successful, and
it may cause problems in the future. To read more
about how to avoid getting large holes click here...
Source of diagram: http://en.wikipedia.org/wiki/Image:Root_Canal_Illustration_Molar.svg