Root canal headaches can be extremely painful; so much so that they may deprive you of your sleep. They are mostly caused due to a flawed root canal treatment, or any new infection that sets in after sometime since placing the crown / completing the root canal treatment. Often, in order to stop the pain, you are forced to resort to a regular dose of pain killers for some relief. However, it is best not to consume pain killers for too long and you should seek medical attention quickly.
To further understand how root canal headaches are caused, here is a brief look at the cause and procedure of root canal treatment itself. Root canal – as the term indicates – is a treatment methodology to cure the infection that sets in the canal of a human tooth. The damage can be the result of an untreated cavity, gum disease or trauma to the tooth, but if left untreated, the infection could affect the nerves and kills the dental pulp, and spread to the other parts of the mouth, destroying the jaw bone and leading to other complications, even to a life threatening extend. If you do not do a root canal treatment, there is not other choice left, but to remove the damaged tooth.
The root canal treatment involves removing all the affected pulp, bacteria, puss, and any other decay from the cavities of the damaged tooth and filling the resulting space with neutral, medicated dental materials; so that, after the treatment, the tooth can stand on its own and perform almost all of its normal functions as if it were a live tooth. The entire procedure of root canal treatment may involve 3-4 sittings with an endodontist, and it may cost a few hundred to thousands of dollars, depending upon the complexity of the situation.
If everything goes fine and the root canal treatment nearly perfect, the tooth will cure within a week's time and it will function almost normally as any other tooth. But if the dentist or endodontist, who had performed the cleaning of the canals, failed to cleanout the canals fully or missed a canal by accident, the infection or bacteria within the canals remains, and within few days, it'll again spread to the jaw bone or nearby tooth, resulting in uncontrollable pain. If someone who has recently undergone a root canal treatment feels persisting pain in the operated tooth that increases in intensity with time, it can be a budding root canal headache, and hence must consider consulting a specialist immediately.
The treatment for root canal headache includes antibiotics to kill the inflammation and pain, and a second root canal treatment to cleanout the newly set in infection.
Tail Piece: Root canal headache is more of a common man's slang than a technical term. Medical science often refer it as the headache due to a miscarried out root canal treatment.