When the nerve inside the tooth is either irritated or becomes necrotic(dead), this can lead to pain and if left untreated can cause abscesses/infections. Pain from such a condition is typically a constant ache and will prevent patients from chewing, talking and generally negatively affect their quality of life.
A root canal is the procedure by which the nerve space inside the tooth is cleaned, shaped and eventually filled to restore function.
Contrary to public belief, root canals are not painful, the procedure is done under local anesthesia and with new technological advances the procedure takes about 45minutes-1 hour (on average).