A root canal therapy involves the treatment of an inflamed pulpal tissue of a diseased or infected tooth. This pulpal tissue is comprised of blood vessels and nerve networks. Each tooth has its own blood and nerve supply.
This pulpal tissue is located inside the narrow space situated in the center of the tooth root or roots. This space is referred too as the canal of a single rooted tooth like a central incisor or canals of a multi-rooted tooth like a molar. Most molars will have at least three channels and some may have four or more.
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When the pulp network becomes damaged due to prolonged dental carious activities or from a traumatic punch or injury, pulp infection usually occurs. This infection may be acute or chronic depending on the situation that causes infection or damage at first.
One of the more common causes of dental nerve damage is trauma. The traumatic teeth initially might be loose, painful and finally tighten but then change (dark). Teeth that are usually involved in this type of situation are the anterior (front) teeth of the maxilla (front) and less frequently (lower jaws) anterior teeth.
If you have never noticed that dental front teeth or dark teeth are dark, you can safely assume that certain teeth have been traumatized. The dental profession refers to this type of teeth as teeth that are not vital and chronic infected with painful symptoms.