For many patients, root canal treatment creates a great sense of fear and anxiety. They associate root canal treatment with pain and discomfort, but this is not true; root canal treatment is used to treat a tooth where the nerve canal system of the tooth is infected.
With a proper local anaesthetic, as is used in our practice, root canal treatment is completely painless. The treatment is usually carried out over two appointments; during the first appointment, the nervous tissue is gently removed and an antibiotic placed inside the nerve canal system to promote healing. During the second appointment the system is cleaned, sterilised and filled, to prevent future infection.
The destroyed tooth structure is then replaced with a high quality filling, or a porcelain crown, if the damage was too extensive.
What is a Root Canal Treatment?
Root canal treatment, or endodontics, is the part of dentistry where the root canal system of an infected, or irreversibly inflamed tooth is opened, debrided, sterilised and filled. This is a wonderful form of treatment where we can save a tooth that would previously have been extracted. Many advances have been made in the techniques used in endodontics and our success rates are now much higher.
At Tzaneen Dental Studio we always advise patients with infected teeth, depending on the degree of infection and damage, to consider root canal treatment above extraction. Nothing in dentistry can replace your own tooth and it is always better to attempt saving a tooth.
Unfortunately we cannot save all teeth with root canal treatment. In some cases we do recommend extraction above endodontics, and although we try our best to sterilise and debride the tooth’s root canal system, there is always the chance that some microorganisms can remain in the root canals even after a proper root canal treatment has been performed. These microorganisms can cause re-infection, in which case the tooth would have to be extracted. Still, it is always advisable to attempt to save a tooth before considering radical, expensive treatments like extraction with a dental implant.
Root Canal Treatment Procedure
Root canal treatment usually starts with an emergency appointment. The patient presents at our practice with pain and discomfort, and as mentioned in the dental examination section, we will do a thorough examination and make a diagnosis.
The treatment begins by anaesthetising the infected tooth and isolating the tooth using a rubberdam. The infected tooth structure is removed with a high speed bur and the nerve canal system is exposed. The infected nerve canal tissue is removed with small nickel titanium hand files and an intra-canal medicament with antimicrobial properties is placed inside the canals. The pulp chamber is covered with a cotton roll and a strong temporary filling placed in the cavity. A second appointment will be made to finish and complete the root canal treatment. The length of the appointment depends on the tooth treated.
The second appointment starts by anaesthetising and isolating the tooth. Isolation is done by rubberdam. We will now remove the temporary filling and remove sufficient tooth structure to gain straight line access into the nerve canals. The coronal portion of the canals is widened to help with straight line access.
The next step of the root canal treatment involves determining the length of the nerve canal. The aim is to go through the apex of the root with small nickel titanium files to maintain apical patency. We attempt to go 1mm through the apex of the root with the small files. An apex locator is used to determine the initial length of the canal. An x-ray is taken with the files at length. We will adjust the length of the files and continue taking x-rays until we find the correct length. The aim in endodontics is to debride the whole nerve canal system right to the tip of the root, maintain apical patency and place our irrigating solution as close to the apex of the root as possible.
Once we have our root canal length determined, we can start with debridement. We like to go with a number eight and number ten files 1mm through the apex to maintain apical patency. We then file with a number 15 and a number 20 hand file to length. Between each file, we rinse the canal with a sodium hypochloride irrigating solution. We also make use of a gliding agent to ease filing and enhance debridement. As soon as our number 20 file sits passively in the canal at length without snagging, we can start using the rotary system.
The Rotary System
We make use of the Dentsply Protaper Next rotary system. The files taper from small to wide, gradually widening and debriding the canal. Between each file, the root canal is thoroughly irrigated with sodium hypochloride. Once we are finished cleaning and shaping the canals with the rotary system, we place the number 20 hand file at length and take an x-ray to confirm that we are still at the correct length. If we are happy, we will continue irrigating the canals with sodium hypochloride. I like to rinse each canal with at least 20ml of sodium hypochloride to ensure proper irrigation. We will place a sterile number ten file 1mm through the apex to make sure I have maintained apical patency. The canals are dried with paper points and we are now ready to obturate the canals.
Obturation is the filling and sealing of the nerve canals with a root canal cement and gutta purcha obturation material. I make use of the Protaper Next obturating system. The process starts by measuring the correct length on the obturator and placing it inside a thermafill oven to warm and soften the gutta purcha around the carrier. We dip a paper point in the root canal cement and place the cement down the canal.
A sterile dry paper point is used to remove any excess cement. The warmed thermafill obturator is placed to length and the excess carrier removed with a high speed bur. Once all the canals are obturated, we take a final x-ray to make sure our obturation is correct. The excess gutta purcha is removed and the canals are sealed with a resin modified glass ionomer cement. The root canal treatment is now complete.
Next, we will do a core build-up with a resin composite filling material as described in the section on restoration. It is important to note that we severely weaken the tooth during a root canal treatment. Firstly, we remove extensive amounts of tooth structure to gain straight line access to the canals. Secondly, we remove the blood supply to the tooth, causing the tooth to become very brittle.
We often recommend placing a porcelain crown on a root canal treated tooth to prevent fracture, which may lead to extraction of a tooth with a great root canal treatment.