The root canal treatment procedure: What steps are involved with endodontic therapy?

A) Placing a rubber dam around your tooth.

After numbing your tooth but before beginning the actual process of performing the root canal treatment, your dentist will stretch a sheet of rubber around your tooth. Dentists call this sheet of rubber a "rubber dam." It is held in place by a small clamp that grasps your tooth.

The purpose of a rubber dam is as follows. Since one of the fundamental goals of root canal therapy is to clean bacteria out of a tooth, and since saliva does have bacteria in it, the placement of a rubber dam allows the dentist to keep your tooth saliva free so it doesn't get recontaminated with bacteria while your root canal treatment is being performed.

B) Gaining access to the nerve area of the tooth.

As a starting point for the process of performing your root canal treatment your dentist must first gain access to that area inside the tooth where the nerve tissue resides. This is accomplished by using a dental drill and making an "access cavity" that extends down to the pulp chamber of the tooth. On posterior teeth this hole is made on the chewing surface of the tooth. On front teeth the access hole is made on the tooth's backside.

C) Cleaning the tooth out.

The next step of the root canal treatment process is for your dentist to clean out the interior of your tooth (the pulp chamber and all root canals). As we discussed previously, this cleaning process removes any bacteria, toxins, nerve tissue, and related debris that are harbored inside your tooth.

For the most part the cleaning process is accomplished by way of using "root canal files" and copious irrigation. Root canal files look like straight pins but on closer inspection you would find that their surface is rough, not smooth. These instruments literally are files and are used as such. Your dentist will work a series of root canal files, each of increasing diameter, up and down in your tooth while simultaneously using a twisting motion. This action will scrape and scrub the sides of the tooth's root canal(s), thus cleaning it out.

As an additional part of the cleaning process, your dentist will wash your tooth out periodically ("irrigate" the tooth) so to help flush away any debris that is present. Traditionally, a number of different solutions have been used for this purpose. Nowadays, sodium hypochlorite (bleach, Clorox) is commonly used. An added benefit of bleach is that it is a disinfectant.

The goal is for your dentist to clean the entire length of the tooth's root canal(s), but not beyond. As a means of determining the length of a canal your dentist may place a root canal file in your tooth and then take an x-ray. Once developed the x-ray picture will reveal if the file extends the full length of the canal or not. Alternatively, your dentist may have an electronic device that can make this same determination when it is touched to a file that has been positioned in a canal.
[ More about how a dentist measures the length of a tooth's root canals. >> ]

Traditionally the filing action of root canal files has been created by way of the dentist manipulating them with their fingers. There are, however, special dental drills (dental drills are called "handpieces") which can hold and twist these files, and your dentist may choose to use one. As a variation on this same theme, there is yet another type of dental handpiece that produces a cleaning motion by way of holding a root canal file and vibrating it vigorously.