Underneath your tooth's outer enamel and within the dentin is an area of soft tissue called the pulp, which carries the tooth's nerves, veins, arteries and lymph vessels. Root canals are very small and thin divisions that branch off from the top pulp chamber down to the tip of the root. A tooth has at least one but no more than four root canals.
When the pulp becomes infected, due to a deep cavity or fracture that allows bacteria to seep in, or injury due to trauma, it can die. Damaged or dead pulp causes increased blood flow and cellular activity, and pressure cannot be relieved from inside the tooth.
Pain in the tooth is commonly felt when biting down, chewing on it and applying hot or cold foods and drinks. Because the tooth will not heal by itself, the infection will spread without treatment. At that point, bone around the tooth will begin to degenerate, and the tooth may fall out.
Pain usually worsens until one is forced to seek emergency dental attention. The only alternative is extraction of the tooth, which can cause surrounding teeth to shift crookedly, resulting in an unfavorable alignment.
Though an extraction is cheaper, the space left behind will require an implant or a bridge, which can be more expensive than root canal therapy. If you have the choice, it is always best to keep your original teeth.
A root canal is a procedure done to save the damaged or dead pulp in the root canal of the tooth by cleaning out the diseased pulp and reshaping the canal. Once cleaned, the canal is filled with gutta percha, a rubberlike material, to prevent recontamination of the tooth. The tooth is then permanently sealed with either a post and/or a gold or porcelain crown, thus allowing patients to keep the original tooth and return to a free-pain meal.