Once a root canal has calmed a painful tooth, it is tempting to stop there. The pain has gone, the tooth feels fine and a crown is one more cost. But for many teeth, the crown is what makes the root canal last. This guide explains why, when a crown is needed, and what having one involves.
What a crown is
A crown, often called a cap, completely covers the visible part of a tooth. It is usually made of metal, ceramic, or porcelain fused to metal. To fit one, the tooth is shaped so the crown can sit over it, and because a laboratory takes time to make the crown, you usually wear a temporary one in between (NHS).
Why a root-treated tooth often needs one
A tooth that needs root canal treatment has usually already lost a fair amount of its structure, to a deep cavity, a large old filling or a crack. The treatment itself then opens a path through the top of the tooth to reach the canals. What is left can be like a hollowed-out shell, particularly in back teeth that take the full force of chewing. A crown holds the tooth together and covers it, so biting forces are spread over the whole tooth.
The research supports this. A systematic review of tooth survival after root canal treatment identified four factors linked to keeping the tooth, and the strongest was a crown placed after treatment (Ng et al., 2010). In a separate study of 203 root-treated teeth, teeth that were not crowned were lost at about six times the rate of crowned teeth (Aquilino & Caplan, 2002). That was one university clinic, so the exact number should not be over-read, but the direction is consistent.
Which teeth need a crown
| Tooth | Usually | Why |
|---|---|---|
| Molars (big back teeth) | A crown | They take the heaviest chewing forces and lose a lot of structure during treatment |
| Premolars | A crown, in most cases | They are narrower and prone to splitting under load |
| Front teeth with little damage | Sometimes a filling is enough | Lighter biting forces; the dentist may keep more natural tooth |
| Front teeth that are broken or heavily filled | A crown | Not enough tooth left to hold a filling well |
The NHS puts it simply: a crown may be needed if the tooth was badly infected (NHS). Your dentist looks at how much healthy tooth is left, where it is in your mouth and how you bite.
What happens if you skip it or delay
- The tooth can crack or split. A crack that runs down into the root often means the tooth cannot be saved.
- Leakage. A temporary filling is not designed to last. If it wears or breaks, bacteria can get back into the tooth and the infection can return.
- More treatment later. A broken root-treated tooth may need a repeat root canal, a post to rebuild it, or extraction and replacement.
What to expect at the crown visits
- 1
Check and plan
Your dentist checks the root canal has settled, then discusses the crown material that suits the tooth and your bite.
- 2
Building up the tooth
If a lot of tooth is missing, a filling (sometimes with a post) builds up a core for the crown to sit on.
- 3
Shaping and impression
Under local anaesthetic where needed, the tooth is shaped and an impression or scan is taken. A temporary crown is fitted.
- 4
Fitting
The finished crown is checked for fit, colour and bite, then cemented in place.
Afterwards, look after the crowned tooth like any other: brush twice a day, clean between your teeth, and keep up your check-ups. The tooth underneath can still decay at the edge of the crown if plaque is left there.
Choosing the crown material
Crowns are made in metal, ceramic or porcelain fused to metal. For back teeth, strength usually matters most. For front teeth, appearance matters more, and a tooth-coloured crown is usually chosen. Your dentist will explain the options that suit your tooth, how each looks and wears, and what each costs.
If you are still deciding whether to save the tooth at all, read Root canal or extraction: how to decide.
Frequently asked questions
Is a crown really necessary after a root canal?
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For most back teeth, yes. A crown placed after root canal treatment is the factor most strongly linked to keeping the tooth in the long term. Front teeth with little damage can sometimes be restored with a filling instead.
How soon after a root canal should I get the crown?
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As soon as your dentist advises, usually once the tooth has settled. Do not leave a temporary filling for months, as it can wear, leak or let the tooth crack.
Can I just have a filling instead of a crown?
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Sometimes, for a front tooth or a tooth with plenty of healthy structure left. For a molar that has lost a lot of tooth, a filling alone is more likely to fail. Your dentist will advise for your tooth.
Does getting a crown hurt?
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A root-treated tooth no longer has a living nerve, but the gum around it can still be sensitive, so local anaesthetic is used where needed. Most people find the crown visits straightforward.
How long does a crown last?
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It varies with the material, your bite, grinding habits and how well you clean around it. Regular check-ups let your dentist spot wear or a leaking edge early.
Sources
- Ng, Mann & Gulabivala (2010), Tooth survival following non-surgical root canal treatment: a systematic review, Int Endod J 43(3):171–89 (accessed 15 October 2026)
- Aquilino & Caplan (2002), Relationship between crown placement and the survival of endodontically treated teeth, J Prosthet Dent 87(3):256–63 (accessed 15 October 2026)
- NHS: Root canal treatment (accessed 15 October 2026)
- NHS: Dental treatments (bridges, dentures, implants) (accessed 13 October 2026)
This article is general information, not a diagnosis or treatment plan. What suits you depends on an examination at the clinic, and every treatment plan and cost is explained before treatment begins.
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