What is a Root Canal, Build-Up, and Crown?

This was a case I treated at my office that (I hope) illustrates a very common situation (a tooth needing a root canal, buildup, and crown) and an explanation of why all those things are needed to save a tooth.

This tooth had a large silver filling with a crack running down the middle and decay around the edges. The tooth was sensitive to cold and to pressure. Even before looking at an x-ray, I’m already in the mindset of this tooth needing a root canal because of the patient’s symptoms.


An x-ray of the tooth shows the filling, the depth of the decay, and how close the decay is to the nerve of the tooth. Symptoms including lingering cold or hot sensitivity (you drink something cold or hot and it is sensitive for a long time after you swallow it), pain to biting pressure, or unprovoked pain could indicate that the tooth needs to have the nerve removed (it is inflamed beyond repair or has become infected).


Due to the depth of the decay and the patient’s symptoms, root canal therapy was performed. This consists of removing the old filling, all decay, and the nerve inside the middle of the tooth, disinfecting the inside of the tooth, and sealing it off to prevent reinfection. This can sometimes take multiple appointments due to the length of the procedure and/or the extent of the infection. A temporary material is placed in the top part of the tooth to cover the root canal material until a buildup and crown is performed.

Many people stop here because this step stops the pain, but at this point the tooth is really in a weakened state – it has a big hole in the middle of it and a clay-like substance where a solid chewing surface should be. This sets the tooth up for fracture and reinfection - this tooth needs a crown as soon as possible.


After the root canal is completed and the tooth has “settled down” (no more pain from that tooth) the patient was brought back and a “buildup” (a.k.a. core or core buildup) and “crown preparation” was performed. A buildup is a filling that is done in the middle segment of the tooth to seal off the roots from future reinfection and to give the tooth enough “body” to make a crown on. A crown preparation means drilling the tooth down to this plateau-style you see here to make room for a crown or “cap” to be made to fit over the buildup.

A crown is needed to protect all of this hard work – a big filling would break over time. A root canal treated tooth is more brittle than other teeth, and is prone to fracture. Many people stop after the root canal because that gets them out of pain, but if they do not get it crowned they could lose that tooth down the road.


The final step to all of this is to crown the tooth. An impression is taken, and then sent to a dental lab that fabricates this pretty (and strong) cover that gives the tooth the best possible chance of surviving long term.

Crowns are made out of numerous materials, including gold alloy, porcelain, and zirconia (which is what we used in this case). This procedure is more expensive than a filling because there is more cost involved in making it than with a filling. However, in many cases it is necessary to save a tooth.

Crowned teeth can still have problems – they can break and they can get decay around the edges if not cleaned properly. But in many cases, including this one (a root canal treated back tooth), crowns are key to the tooth’s longevity.


Reply with any questions or comments you might have about this process, I’d be glad to try and help out. On the other hand, feel free as always to call us at (205) 290-7878.

1 Response

  1. Jamie
    May 23, 2013

    It’s definitely true that you need to crown the tooth as soon as you can after the root canal is done. The expense of the crown — not to mention the trouble of the root canal itself — usually discourages us from hurrying on towards the crown. But let me tell you from personal experience: if you don’t, the tooth may BREAK. If it breaks beyond the gum-line (mine did) then you’re outta luck — that tooth has to be pulled. I.E. the whole expense/trouble of the root canal in the first place (trying to stop the pain but avoid losing the tooth) is rendered moot. Get a crown done ASAP afterwards, and you won’t have to worry about it anymore. :)