A crown and a root canal solve different problems
A crown is a cover that protects and rebuilds the outside of a tooth. A root canal treats the inside, when the pulp is infected or dying. One does not require the other, and the order is set by the condition of the nerve, not by the plan to place a crown.
The common link is the reverse direction: a root-treated back tooth usually needs a crown afterwards, as explained in do I need a crown after a root canal. The other way round, a crown on a healthy tooth needs no root canal at all.
When a crown alone is enough
A tooth with a large filling and thin walls that is likely to split. A cracked tooth where the crack has not reached the nerve. A tooth worn down by grinding or acid. A tooth that needs a change of shape or colour that a filling cannot give. A tooth next to a gap that will support a bridge.
In each case the nerve is healthy and the dentist is protecting the tooth rather than treating infection. Materials and where each is used are covered in types of dental crowns.
How the dentist checks the nerve first
Before shaping the tooth, the dentist tests its response to cold, taps it, and takes an X-ray. A tooth that responds normally and has no shadow at the root tip is safe to crown. A tooth with lingering pain, tenderness to bite or a root-tip shadow is not, and treating the nerve first avoids a failed crown.
A tooth with an abscess or sinus on the gum needs root canal before the crown, and the crown is only made afterwards.
The small chance of needing a root canal after a crown
Shaping a tooth for a crown removes tooth structure and generates heat and vibration, and the nerve of a tooth that was already stressed by deep decay or a big filling can become inflamed. A small proportion of crowned teeth need a root canal later. The dentist can often tell beforehand which teeth are at higher risk, and should say so.
If a root canal is needed after the crown is in place, it is done through a small hole drilled in the crown, which is then repaired. In some cases the crown has to be remade. See what happens when you get a crown (cap) for the sequence, and our crowns and bridges page for when crowns are recommended.
Common questions
Can I get a crown on a tooth that still has its nerve?
Yes, and this is the most common situation. The tooth is numbed, shaped and fitted with a temporary crown while the permanent one is made. Some sensitivity to hot and cold for a few days is normal and settles.
Why do some dentists do a root canal before a crown?
Because the nerve is already damaged or the tooth is so broken down that a post inside the root is needed to hold the crown. In those teeth the nerve is treated first. Where the nerve is healthy, no root canal is needed.
Does shaping a tooth for a crown kill the nerve?
Not usually. Most teeth tolerate it well, although a minority, especially teeth with deep fillings or past injury, can become inflamed and later need a root canal. The risk is higher when a lot of tooth is removed.
Is a crown cheaper than a root canal and crown together?
Yes, because it skips the root canal fee. The dentist decides on the condition of the nerve rather than cost. Crown ranges by material are on the crown cost page, and root canal ranges are on the root canal cost page.
About this page
This page is general information, not a diagnosis or a quotation. Prices are prevailing Lucknow market ranges. Your own treatment and cost are determined after an examination. For questions about your own case, call +91 83036 12717.