FAQ - Root Canals – The Center for Dental Education

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Questions about Root Canals

What IS a root canal?
Why might I need a root canal?
When my tooth hurts, does that mean I need a root canal?
Might I need a root canal even if my tooth doesn’t hurt?
Is getting a root canal a painful experience?
After a root canal is done, what is the chance that it will work and I won’t have pain again?
How long will it take for the pain to go away after a root canal is done?
Why is a root canal procedure so expensive?
Are there different ways to do a root canal?
After the root canal is done, what must be done to the tooth?
What is the probability of success for a root canal treatment?
Why does the dentist use that rubber sheet in my mouth during the root canal procedure?
Why not just get the tooth removed – the root canal is so expensive – especially when adding in the crown afterward?
If I have the tooth removed, will the empty space cause any problems?
If I have the tooth removed and an implant and crown placed, is that a more successful long-term solution than the root canal?
What is used to fill the roots of the teeth when a root canal is done?

Answers about Root Canals:

What IS a root canal? Actually the term “root canal” refers to a structure within the tooth, not to any procedure. People often refer to getting a root canal, but it is the therapeutic cleaning out of the root canal itself, called root canal therapy or RCT that is what you pay the dentist to do. ………………..BACK to questions
Why might I need a root canal? You will need root canal therapy if the canal system within the tooth becomes infected with bacteria. The tooth has such a poor circulation system that infection is not well fought off by the immune system in that area and the infection flourishes and the nerves inside the pulp and root canal system respond with pain, and if the infection comes out the apex of the roots into the bone, there will be pain just to put even a light pressure on the tooth as well. Even if the source of the bacterial invasion into the tooth is arrested by removal of decay and filling the area, once the pulp has been exposed, it is most likely that the only solution will be to remove the pulp in the chamber and canals completely………………… BACK to questions
When my tooth hurts, does this mean I need a root canal? Not necessarily. There are many reasons why the tooth might hurt. But, if there is decay that has obviously invaded the pulp chamber, or is clearly very close to it, or there is some history of trauma to the tooth which might have disrupted the blood supply to the tooth through the roots, a root canal may be needed. If the pain is throbbing, a classic “tooth ache” it is pretty clear a root canal will be necessary. If the tooth is sensitive to cold and hurts for just a few seconds, that is suggestive of less serious problems. If the tooth is sensitive to heat – that is more of an indication that there is something wrong with the pulp. ………………..BACK to questions
Might I need a root canal even if my tooth doesn’t hurt? There are pulp testing procedures that the dentist can do which tests the vitality of the pulp – basically tests the conductivity of electricity through the tooth – if it doesn’t pass electricity (very low levels), then it may be necrotic or dead. It may NOT hurt, because the pulp including the nerve are not living and functioning anymore – but that tooth needs root canal therapy too. This may have been caused by trauma to the tooth which disrupted the blood flow to the pulp of the tooth………………… BACK to questions
Is the root canal treatment painful to experience? We will often prescribe antibiotics to attempt to reduce the infection inside the tooth before the root canal therapy is attempted, so the procedure itself is less painful than it might be otherwise. If pain medications and antibiotics are not effective to calm things down and the pulp must be removed, the dentist must VERY carefully inject anesthetic INTO the pulp chamber so the nerves are deadened before starting to remove the pulp. This normally requires injecting just a little at the point of entry, letting that numb that area, and then advancing the needle deeper a little at a time, injecting more anesthetic at many levels before the whole pulp is numb and working on it is comfortable. A dentist that is in too much of a hurry may certainly expose you to more pain and discomfort during the procedure than is strictly necessary. This has lead to the “root canal” having such a bad reputation…………………BACK to questions
After a root canal is done, what is the chance that it will work and I won’t have pain again? There is a very high, around 95%, chance that root canal therapy that is done well will solve the problem with the tooth. Immediately after the pulp has been removed and the inside of the tooth cleaned out and filled, there can be NO pain from the inside of the tooth, that is a certainty, because there are no nerves left there. There may still be pain from the bone at the apex of the root, if the infection extended into that area – but it will resolve soon if the source of the infection from the tooth has been eliminated. Typically, a patient with the infection beyond the tooth into the bone is prescribed antibiotics to help resolve this infection. Once the situation normalizes in the area it is expected that you will have no pain or problems with the tooth again. But, IF there is still some pulp tissue, including nerves that still connect to the body through the one apex, some pain may still be present. This, however, is unusual………………… BACK to questions
How long will it take for the pain to go away after root canal therapy is done? The throbbing pain from within the tooth, the toothache, will be gone as soon as the anesthetic wears off. Any pain or sensitivity originating from the bone may take a couple of days to resolve, but won’t be as serious…………………BACK to questions
Why is a root canal procedure so expensive? This is because of the time required to do it correctly. If done by an endodontist, you are also paying a premium rate for his time because of the additional training he needed to be able to handle particularly tricky cases. Whoever is doing the root canal therapy, there is a need to make certain that ALL of the pulp tissue, nerves, vessels, connective tissue is removed completely, AND that it is removed from every root or canal. Typically one root has one canal, but there are exceptions. Some canals are more difficult to find than others. Notoriously, the upper first molar that has one of the three roots that often has two canals in it, but the second one can be quite difficult to find. One needs to know exactly where it MIGHT be, and then carefully probe the area to find some indication it is there, and then widen into it. Also, these canals are being cleaned out JUST to the apex of the tooth, while the dentist cannot see what he is doing. Some of it is done by feel, and some is done by checking every step of the way using X-rays. Again, the difficulty requires more time to be spent, and time is money…………………BACK to questions
Are there different ways to do a root canal? Yes – the traditional approach is using long thin needle-like files with sharp fluted edges to enter each canal and remove the tissue and scrape down the inside of each by hand. Many dentists these days use similar files that are connected to a rotating handpiece – this is called rotary instrumentation of the root canal system. Rotary instrumentation can be faster and it can be easier and it can be better, when done by someone familiar with the method…………………BACK to questions
After the root canal is done, what must be done to the tooth? The root canal system that has been totally cleaned out must be filled with something. There are a variety of materials that may be used, but a SEALER is typically also used which is a thin paste which may be pushed into small accessory canals extending from the main canals. So, some FILLER is placed which pushes the sealer with significant pressure into any small canal or irregularity in the canals. This filling is done for the canals and the pulp chamber as well, and then a crown is typically done for the tooth, protecting the tooth structure as weakened by the procedure. Sometimes, when there is significant parts of the tooth missing, one or more cusps missing because of decay or fracture, for instance – some kind of POST is screwed or cemented into one of the canals such that it will help to retain a material used to rebuild the bulk of the tooth so that a crown has something to hold onto…………………BACK to questions
What is the probability of success for a root canal treatment? Long term success, where the tooth is never again symptomatic and the bone around the apex of the roots returns and remains solid and dense, is over 90%, depending on the difficulty of the situation in the first place. For teeth where the canals are quite curved, and there are many side branches of the canals, present more of a challenge. They can still be managed by a specialist to achieve a similarly high success rate…………………BACK to questions
Why does the dentist use that rubber sheet in my mouth during the root canal procedure? They should! Most dentists do but not all. If they do not, then during the procedure where the tooth is open into the canal system, there can be contamination by saliva, and this has been shown to significantly reduce the overall success of the treatment. In fact, legally, if a dentist is taken to court because of a patient’s dissatisfaction with the results of the therapy, if the dentist cannot show evidence from the progress notes in the patient’s file that a rubber dam was used, the dentist will lose the case!………………..BACK to questions
Why not just get the tooth removed – the root canal is so expensive – especially when adding in the cost of the crown afterward? You certainly have the option of doing that, but then the consequences of having a missing tooth can be serious too. Eventually, you may need to have the space filled with another tooth, and any procedure whereby that is accomplished is far more expensive than the root canal and single crown…………………BACK to questions
If I have the tooth removed, will the empty space cause any problems? Quite likely. What happens is that the teeth behind the space will eventually TIP into the space. This causes quite a disruption in the occlusion, and pressures on the teeth in directions they were not designed to support. There can also be interference in the movement of the jaws from side to side because of the attendant malocclusion. Now – some people do well with missing teeth for long periods of time, but that is rather unusual…………………BACK to questions
If I have the tooth removed and an implant and crown placed, is that a more successful long-term solution than the root canal? Those dentists that place a lot of implants will have you believe that their success is better than that of root canal therapy. I would say that the jury is still out. The relative success of the two approaches depends a lot on the skill and care of the dentist doing the root canal therapy or the implant and crown – both can be done poorly so that the lifetime is compromised. In my own mouth I would rather save the root of the tooth if at all possible – the root of the tooth is, basically, an implant, but a much more natural one than one made out of titanium…………………BACK to questions
What is used to fill the roots of the tooth when a root canal is done? The classic material is called Gutta Percha. It is kind of rubbery clay that can be fashioned into “points” which are tapered needle like pieces which are designed to fit down into the canals. The correct size and taper is selected and it is placed by hand, with a sealer cement between it and the canal surfaces. The tight fit of the point into the canal provides considerable pressure to push the sealer into any accessory canals coming from the sides of the main canals, and this is important for the success of the procedure. Sometimes dentists use a hot Gutta Percha device, which extrudes a warm snake-like strand of gutta percha into the canal, which is then pressed down using a hand instrument. There are advantages to this if the canal system has a lot of irregularities and not an even taper from the pulp chamber to the apex. Other filling materials and cements have been suggested over the years, but the “gold standard” is still gutta percha with some kind of sealer, however it is placed…………………BACK to questions