One of the most common causes of dental pain or toothache is nerve pain from a tooth, that has inflammation, called pulpitis. This inflammation can be caused by decay, a large filling with close proximity to the nerve or trauma. Pulpitis can cause excruciating pain or sensitivity to hot and cold.
There are two classifications of pulpitis. Reversible pulpitis is when a tooth is sensitive to hot or cold, but the pain quickly subsides with the removal of the stimulus. Reversible pulpitis may recover without requiring extraction of the tooth or a root canal. Irreversible pulpitis is where the tooth is experiencing intense pain that is constant and comes about without provocation. Irreversible pulpitis is only resolved by extraction of the tooth or root canal therapy.
A root canal is a procedure that removes the nerves and blood vessels, that reside in the hollow portion of the tooth. The doctor will open the tooth, clean, shape, and decontaminate the inside of the tooth before it is filled with a special filling material, called guttapercha. The tooth is then restored with resin and a crown to protect the tooth from potential fracture.