When a tooth needs a crown
A crown covers the entire visible tooth, holding what remains together and taking the chewing load off it. That becomes necessary in a fairly specific set of situations:
- After root canal therapy — a treated back tooth becomes brittle and is prone to splitting without full coverage
- A large fracture or crack — where a filling would act as a wedge and worsen the split
- A very large old restoration that has failed — when there is more filling than tooth left, a replacement filling has nothing sound to bond to
- Severe wear — from grinding or acid erosion, where the tooth has lost height as well as surface
- Supporting a bridge — the teeth either side of a gap are crowned to carry it
- Restoring a dental implant — the crown is the part of an implant you actually chew with
A crown is not automatically the answer to a large filling. Where enough sound tooth remains, an onlay or a well-bonded composite keeps more of your own tooth — and keeping tooth structure is almost always the better long-term decision.
Crown materials and what they suit
All-ceramic
Ceramic transmits light in a way that resembles enamel, which is why it is the usual choice anywhere the tooth is visible. Modern ceramics such as zirconia and lithium disilicate are strong enough for back teeth as well. There is no metal core, so no dark line appears at the gum as the gums recede over the years.
Porcelain fused to metal
An older approach with a metal substructure under a porcelain surface. Durable and well proven, but the metal margin can become visible at the gumline over time. We use it selectively rather than by default.
Gold and metal alloys
Still the most forgiving material mechanically — kind to the opposing tooth and able to work in very thin sections, which means removing less tooth structure. Appearance is the only reason it has fallen out of fashion, so it remains a sensible option for molars that do not show.
The right material depends on where the tooth sits, how much space there is, how hard you bite, and whether you grind. We will explain the trade-off rather than simply presenting one option.
How a crown is made and fitted
1. Assessment and planning
We check that the tooth is restorable, that the gum around it is healthy, and that the root is sound. Where decay has reached the nerve, root canal therapy comes first.
2. Preparation
Under local anaesthetic, the tooth is shaped to make room for the crown — enough for strength, no more than necessary. Any decay is removed and the tooth built up underneath if required.
3. Digital impressions
A scan captures the prepared tooth, the neighbouring teeth and how your bite meets. Shade is matched at this stage against your surrounding teeth.
4. Temporary crown
A temporary protects the tooth while the permanent crown is made. It is deliberately easier to remove, so avoid very sticky food on that side and take care with floss.
5. Fitting
The permanent crown is tried in, checked for fit, contact with the neighbouring teeth, bite and appearance, then cemented. Adjustments happen before cementation, not after.
Expect two appointments a couple of weeks apart. Tell us if the bite feels high once the anaesthetic wears off — a crown that sits proud puts all your chewing force on one tooth, and it is a quick adjustment.
Inlays and onlays — the middle option
An inlay or onlay is a custom-made restoration bonded into or over a prepared area, sitting between a filling and a full crown. An inlay fits within the cusps; an onlay covers one or more of them.
- Keeps more tooth than a crown, which has to be prepared all the way round
- Stronger than a large direct filling, because it is made outside the mouth and bonded in as one piece
- Well suited to large back-tooth cavities where the cusps are still sound
- Ceramic or composite, matched to the tooth
Where an onlay will do the job, we would rather place an onlay. Once a tooth is crowned, that decision cannot be walked back.
Bridges: spanning a gap
A fixed bridge replaces a missing tooth with a false tooth — a pontic — carried by crowns on the teeth either side. It is cemented in place and not removable.
What a bridge involves
The teeth on both sides of the gap have to be prepared for crowns, whether or not they need treatment for their own sake. That is the central trade-off: healthy enamel is removed from two teeth in order to replace one.
Bridge or implant?
Where the neighbouring teeth are sound and untouched, a dental implant is usually the more conservative choice — it replaces the missing tooth without involving them. Where those teeth already carry large restorations and would benefit from crowns anyway, a bridge can be the more sensible option, and it is quicker: weeks rather than months.
Living with a bridge
You cannot floss between the pontic and the supporting teeth in the ordinary way. Cleaning underneath it with a floss threader or interdental brush is what determines how long it lasts — decay at the margins of the supporting teeth is the usual reason a bridge fails.
Making a restoration last
Ceramic does not decay, but the natural tooth underneath still can, and the join between crown and tooth is where decay starts. A crown does not make a tooth immune to anything.
- Clean along the gumline where the crown meets the tooth, every day
- Keep to your hygiene appointments so the margins can be checked
- Wear a night guard if you grind — it is the most common cause of ceramic fracture
- Avoid chewing ice, pens and hard sweets on a restored tooth
- Mention any bite change or sensitivity early rather than waiting
Gum health matters just as much: see our gum disease prevention guide, since bone loss around a crowned tooth will end its life sooner than the ceramic ever would.
Crowns and bridges FAQ
How long do crowns and bridges last?
+Published averages sit somewhere between ten and fifteen years, but the range in practice is enormous. What decides it is not the ceramic — it is whether decay starts at the margin and whether the gum and bone stay healthy. Home care and regular checks matter more than the material.
Does getting a crown hurt?
+Preparation is done under local anaesthetic, so you should not feel pain. Some sensitivity to hot and cold between the preparation and fitting appointments is normal while the temporary is in place, and it settles once the permanent crown is cemented.
Should I choose a bridge or an implant?
+If the teeth either side of the gap are healthy and untouched, an implant is generally the more conservative option, because a bridge requires preparing them. If those teeth already have large restorations and would benefit from crowns anyway, a bridge can make more sense — and it takes weeks rather than months.
Can a crown fall off?
+Yes, though it is uncommon. It usually means the cement has failed or decay has developed underneath. Keep the crown, avoid chewing on that side, and contact us — a crown that is otherwise sound can often be recemented.
Will a crown match my other teeth?
+Shade is matched against your surrounding teeth at the impression appointment. Worth knowing: whitening does not affect ceramic, so if you are planning to whiten, do it before the crown is made — otherwise it will match the shade you had, not the shade you end up with.