Root canal therapy is a treatment used to repair and save a tooth that is badly decayed or infected.
Root canal therapy is performed when the pulp which is composed of nerves and blood vessels in the tooth becomes infected or damaged. During root canal therapy, the pulp is removed, and the inside of the tooth is cleaned and sealed.
People fear root canals because they assume they are painful. Actually, most people report that the procedure itself is no more painful than having a filling placed. The discomfort experienced in the period leading up to seeking dental care is truly painful, not the procedure itself.
What Is Dental Pulp?
The pulp or pulp chamber is the soft area within the center of the tooth and contains the nerve, blood vessels, and connective tissue. The tooth’s nerve is in the “root” or “legs” of the tooth. The root canals travel from the tip of the tooth’s root into the pulp chamber.
A tooth’s nerve is not vitally important to a tooth’s health and function after the tooth has emerged through the gums. Its only function is sensory – to provide the sensation of heat or cold. The presence or absence of a nerve will not affect the day-to-day functioning of the tooth. However, after treatment the tooth is less viable and more susceptible to fracture.
Why Does the Pulp Need to Be Removed?
When pulp is damaged, it breaks down, and bacteria begin to multiply within the pulp chamber. The bacteria and other dying pulp remnants can cause an infection or abscessed tooth. An abscess is a pus-filled pocket that forms at the end of a tooth’s root. In addition to an abscess, an infection in the root canal of a tooth can cause:
- Swelling that may spread to other areas of the face, neck, or head
- Bone loss around the tip of the root
- Drainage problems extending outward from the root. A hole can occur through the side of the tooth, with drainage into the gums or through the cheek into the skin.
The Root Canal Therapy Procedure
Root canal therapy requires one or more office visits and can be performed by a dentist or endodontist. An endodontist is a dentist who specializes in the causes, diagnosis, prevention, and treatment of diseases and injuries of the teeth’s dental pulp. The choice of which type of dentist to use depends to some degree on the difficulty of the root canal procedure needed in your particular tooth and the general dentist’s comfort level in working on your tooth. Your dentist will discuss who might be best suited to perform the work in your particular case.
The first step in the procedure is to take an X-ray to see the shape of the root canals and determine if there are any signs of infection in the surrounding bone. Your dentist or endodontist will then use local anesthesia to numb the area near the tooth. Actually, anesthesia may not be necessary, since the nerve is dead, but most dentists still anesthetize the area to make the patient more relaxed and at ease.
Next, to keep the area dry and free of saliva during treatment, your dentist will place a rubber dam (a sheet of rubber) around the tooth.
An access hole will then be drilled into the tooth. The pulp, along with bacteria and related debris, is removed from the tooth. The cleaning-out process is accomplished using root canal files. A series of these files of increasing diameter are each subsequently placed into the access hole and worked down the full length of the tooth to scrape and scrub the sides of the root canals. Water or sodium hypochlorite is used periodically to flush away the debris.
Once the tooth is thoroughly cleaned, it needs to be sealed. Some dentists like to wait a week before sealing the tooth. For instance, if there is an infection, your dentist may put a medication inside the tooth to clear it up. Others may choose to seal the tooth the same day it is cleaned out. If root canal therapy is not completed on the same day, a temporary filling is placed in the exterior hole in the tooth to keep contaminants out between appointments.
At the next appointment, to fill the interior of the tooth, a sealer paste and a rubber compound called gutta-percha are placed into the tooth’s root canal. To fill the exterior access hole created at the beginning of treatment, a filling is placed.
The final step may involve further restoration of the tooth. Because a tooth that needs root canal therapy often is one that has a large filling or extensive decay or other weakness, a crown, crown and post, or other restoration often needs to be placed on the tooth to protect it, prevent it from breaking, and restore it to full function. Your dentist will discuss the need for any additional dental work with you.
What Should One Expect After Root Canal Therapy?
Root canal therapy should relieve the pain you feel. Until your root canal procedure is completely finished – that is, the permanent filling is in place and a crown, if needed, is in place – it’s wise to minimize chewing on the tooth under repair. This step will help avoid recontaminating the tooth’s interior and also may prevent a fragile tooth from breaking before the tooth can be fully restored.
For the first few days following the completion of treatment, the tooth may feel sensitive due to natural tissue inflammation, especially if there was pain or infection before the procedure. This sensitivity or discomfort usually can be controlled with over-the-counter pain medications such as ibuprofen (Advil, Motrin) or naproxen (Aleve). Most patients can return to their normal activities the next day.
Complications of Root Canal Therapy
Despite your dentist’s best efforts to clean and seal a tooth, new infections might emerge. Among the likely reasons for this include:
- More than the normally anticipated number of root canals in a tooth (leaving one of them uncleaned)
- An undetected crack in the root of a tooth
- A defective or inadequate dental restoration that has allowed bacteria to get past the restoration into the inner aspects of the tooth and recontaminate the area
- A breakdown of the inner sealing material over time, allowing bacteria to recontaminate the inner aspects of the tooth
Sometimes re-treatment can be successful. Other times, endodontic surgery must be tried in order to save the tooth. The most common endodontic surgical procedure is an apicoectomy, or root-end resection. This procedure relieves the inflammation or infection in the bony area around the end of your tooth. In this procedure, the gum tissue is opened, the infected tissue is removed, and sometimes the very end of the root is removed. A small filling may be placed to seal the root canal.