Cracked Tooth: Symptoms, Repair Options and Cost

The classic sign of a cracked tooth is sharp pain when you release your bite rather than when you clench. Cracks do not heal and they spread, so a tooth that could be saved with a crown this month can become an extraction next year. How repairable it is depends almost entirely on which type of crack you have.

The Bite and Release Test

If you take one thing from this page, take this.

Bite firmly on something like a cotton bud or a piece of soft food with the suspect tooth, then let go. If the sharp pain comes as you release, that is close to diagnostic of a crack.

The reason is mechanical. Biting down opens the crack slightly and pushes the two segments apart. Releasing lets them snap back together, and that movement pinches the nerve tissue inside. Pressure alone does not do it. The snap back does.

Pain only while clenching, without the release element, is more often a high filling or an inflamed nerve.

The other giveaway is that cracked teeth are unpredictable. It hurts on one mouthful and not the next, depending on exactly where the force lands. People often assume they are imagining it for that reason, and delay.

The Five Types, and What Each One Means

Dentists classify cracks using a framework from the American Association of Endodontists, and the type decides both treatment and whether the tooth survives.

1. Craze lines

Hairline cracks in the outer enamel only. Extremely common in adult teeth, painless, and essentially cosmetic. They do not need treating and do not weaken the tooth. Our page on craze lines covers them properly.

Prognosis: not a problem.

2. Fractured cusp

One of the pointed corners of a back tooth breaks away, usually alongside an existing large filling. Often surprisingly painless, because the crack tends to run away from the pulp rather than into it.

Treatment: usually a crown, sometimes a large filling or onlay. Prognosis: good.

3. Cracked tooth

A crack running from the biting surface downwards, still in one piece but travelling towards the pulp. This is the one that produces the bite and release pain.

Caught early it can be crowned, which binds the tooth together and stops the crack progressing. Left alone the crack extends, reaches the pulp, and then needs root canal treatment as well.

Treatment: crown, with root canal if the pulp is involved. Prognosis: good if treated early, and this is where timing genuinely changes the outcome.

4. Split tooth

The crack has progressed all the way through and the tooth is in two separate segments. This is what a cracked tooth becomes if it is ignored long enough.

Treatment: usually extraction. Occasionally one segment can be saved. Prognosis: poor.

5. Vertical root fracture

A crack starting in the root and travelling upwards, often invisible on the biting surface and difficult to spot even on an X-ray. Usually found in teeth that have already had root canal treatment.

Treatment: extraction, in most cases. Prognosis: poor.

Why Waiting Costs You the Tooth

Cracks do not stabilise. Every time you chew, the two sides of the crack flex against each other and the crack extends slightly.

The sequence is predictable. A crack confined to the crown can be crowned, and the tooth is fine. Once it reaches the pulp you need root canal treatment as well. Once it splits the root, the tooth comes out.

Moving between those stages can take months or years, and it can also happen on one unlucky mouthful. There is no way to predict which, which is the argument for dealing with it while the answer is still a crown.

Cracks also let bacteria into the pulp, so an untreated crack often presents eventually as an abscess rather than as pain on biting.

Why Teeth Crack

• Large old fillings. The most common reason. A big filling leaves thin walls of tooth around it, and those walls flex until one gives.
• Grinding and clenching. Sustained heavy loading, often at night without knowing.
• Biting something hard. Ice, olive stones, popcorn kernels, or the classic, using teeth to open packaging.
• Root-treated teeth, which are more brittle because the internal blood supply has gone. This is why crowning them afterwards is recommended.
• Sudden temperature change, such as something very cold straight after something hot.
• Trauma, a blow to the face or a fall.
• Age. Enamel accumulates decades of microscopic damage.

How It Is Diagnosed

Cracked teeth are genuinely difficult to find, which is worth knowing so you are not surprised if it takes more than a glance.

X-rays often show nothing. A crack running vertically is invisible on a two-dimensional image taken from the side, because there is no gap for the X-ray to pass through. A normal X-ray does not rule out a crack.

The bite test reproduces the pain and identifies which tooth.

Removing an existing filling sometimes reveals a crack running underneath it that was hidden.

Transillumination, shining a bright light through the tooth, makes some cracks visible as a dark line.

A crown or filling that keeps failing in the same tooth is itself a clue.

Repair Options and Cost

Composite bonding for small chips and shallow cracks. Tooth-coloured material bonded on in one appointment. UK market rates start around £100. Not enough on its own for a crack that runs into the tooth, because it does not hold the segments together.

A crown is the main treatment for a genuinely cracked tooth. It encircles the tooth and binds it, which is exactly what a cracked tooth needs. Our crowns start from £995, against UK market rates typically running £600 to £2,500.

Root canal treatment where the crack has reached the pulp, from £425 with us. Usually followed by a crown. Market rates elsewhere commonly run £600 to £1,400.

Extraction from £195 where the tooth is split or the root is fractured. If a tooth does come out, our guide to replacing a missing tooth covers the options.

On the NHS, bonding and simple extractions fall under Band 2 and crowns under Band 3. Band charges change each April, so check the current figures.

What to Do Right Now

• Stop chewing on that side. Every bite extends the crack.
• Avoid hard and chewy food entirely until it is assessed.
• Avoid temperature extremes, which make the tooth flex.
• Keep it clean, gently.
• Over-the-counter pain relief as directed on the packet if needed.
• Book promptly. This is not a wait-and-see situation, because the treatment options narrow over time.

If a piece has broken off and the tooth is now sharp or painful, that is an emergency appointment. Keep any fragment in milk in case it can be reattached.

Frequently Asked Questions

How do I know if my tooth is cracked?

Sharp pain when you release a bite rather than when you clench is the classic sign, along with pain that comes and goes unpredictably. Cracks are often invisible and frequently do not show on X-rays.

Can a cracked tooth heal itself?

No. Enamel and dentine cannot repair, so a crack stays and gradually extends with normal chewing.

How much does it cost to fix a cracked tooth in the UK?

Depends on the crack. Bonding from around £100, crowns from £995 with us against a £600 to £2,500 market range, root canal from £425, extraction from £195. NHS bonding is Band 2 and crowns Band 3.

Can a cracked tooth be saved?

Usually, if the crack is still within the crown of the tooth. A crown binds it and stops progression. Once the tooth has split into segments or the root has fractured, extraction is normally the only option.

Why does my cracked tooth only hurt sometimes?

Because pain depends on force landing at the exact angle that flexes the crack. That inconsistency is characteristic, and it is why people convince themselves it is nothing.

Will an X-ray show a cracked tooth?

Often not. Vertical cracks are frequently invisible on standard X-rays because there is no gap for the image to capture. A clear X-ray does not mean there is no crack.

Is a cracked tooth an emergency?

Not usually, unless a piece has broken off leaving sharp edges or significant pain, or there is swelling. It is urgent in the sense that delay narrows your options rather than that it needs treating tonight.

Can I just have a filling instead of a crown?

For a shallow crack or small chip, yes. For a crack running into the tooth, a filling sits inside it and does not hold the segments together, so the crack keeps spreading. A crown wraps around and binds it, which is why it is recommended.

Get a Cracked Tooth Assessed in Elephant & Castle

If biting on one tooth gives you a jolt when you let go, get it looked at while a crown is still the answer. Cracks are the one dental problem where the difference between acting now and waiting a year is often the difference between keeping and losing the tooth.

Call 020 7928 4474 or book online. We are in Elephant and Castle, minutes from Waterloo, Borough and London Bridge, and we hold emergency slots daily. If the tooth is currently painful, our guide to stopping severe tooth pain covers the next few hours.

Our fees start from the figures quoted. Market ranges are indicative UK figures from published 2026 guides. NHS band charges change each April. This page is general information, not a diagnosis. Last reviewed August 2026.