A cracked tooth is exactly what it sounds like — a tooth that has a fracture running through it. Cracks can range from tiny surface lines (which are harmless) to deep fractures that split the root and may threaten the tooth.
Cracked teeth are one of the most common causes of dental pain in adults. They can be difficult to diagnose because cracks are not always visible on X-rays or even with the naked eye.
There are several types of crack, and the treatment and prognosis depend heavily on the type and depth:
Craze lines — tiny, surface cracks in the enamel only. Very common and harmless. No treatment needed.
Fractured cusp — a piece of the outer chewing surface breaks off. Usually does not affect the nerve. Often treated with a filling or crown.
Cracked tooth — a crack that extends from the chewing surface towards the root. Can affect the nerve over time. Treatment ranges from a crown to root canal treatment, depending on depth.
Split tooth — the tooth has completely split into two separate segments. The tooth is usually not salvageable.
Vertical root fracture — a crack that starts in the root. Often has few symptoms until infection develops. Usually requires extraction.
What causes cracked teeth?
Teeth can crack for several reasons:
Chewing hard foods — ice, hard sweets, popcorn kernels, or crusty bread
Tooth grinding (bruxism) — the sustained pressure over time fatigues and cracks the enamel
Large fillings — teeth with large old fillings have less natural tooth structure and are more prone to fracture
Trauma — a blow to the mouth from an accident or sport
Sudden temperature changes — for example, eating very hot food followed by a cold drink
Age — teeth naturally become more brittle with age
Signs and symptoms
Cracked teeth can be frustratingly difficult to identify. Typical symptoms include:
A sharp pain when biting or chewing — often on release of biting pressure rather than on biting down
Intermittent pain — not constant, and often hard to reproduce
Sensitivity to cold, hot, or sweet foods that lingers briefly
Discomfort that moves around and is hard to pinpoint
Difficulty chewing on one side
If you have a constant, severe ache combined with swelling or a bad taste, the crack may have allowed infection to develop. Please seek urgent dental attention.
How are cracked teeth treated?
Treatment depends entirely on the type, location, and depth of the crack. Your dentist will carry out a thorough examination, which may include special bite tests, dye staining, transillumination (shining a bright light through the tooth to reveal cracks), and X-rays. Even with all of these, some cracks remain difficult to see, and treatment recommendations are sometimes made on clinical symptoms alone.
Craze lines — no treatment needed. Cosmetic bonding may be offered if appearance is a concern.
Fractured cusp — a new filling or a crown to protect and restore the tooth.
Cracked tooth (not yet reaching nerve) — a crown to hold the tooth together and prevent the crack from deepening. This is often the best way to save the tooth.
Cracked tooth (involving the nerve) — root canal treatment followed by a crown.
Split or vertically fractured tooth — extraction is usually required. Your dentist will discuss options for replacing the tooth.
Unfortunately, there is no guarantee that a cracked tooth can be saved — this depends on how deep and in what direction the crack runs.
What you can do at home
Whilst you are waiting for your appointment:
Avoid biting on the sore side of your mouth.
Steer clear of very hard foods like ice, hard sweets, and crusty bread.
Avoid temperature extremes if the tooth is sensitive.
Take over-the-counter pain relief (paracetamol or ibuprofen) if needed, as directed on the packet. Avoid ibuprofen if you have asthma, cardiovascular disease, stomach problems, kidney issues, take blood-thinning medications, or are pregnant.
To reduce the risk of further cracking in other teeth, consider:
Wearing a nightguard if you grind your teeth
Not chewing ice, hard sweets, or other very hard foods
Wearing a mouthguard during contact sports
When to see your dentist
Book an appointment soon if:
You have pain on biting that is not improving
A tooth has visibly broken or a piece has come off
Sensitivity is increasing or not settling
Seek urgent care if you develop swelling, a bad taste, or constant throbbing pain — these suggest infection has developed. Contact your practice or call NHS 111 outside of hours.
This leaflet is for general information only and does not replace professional dental advice. Your dentist will discuss your individual circumstances and any risks and treatment specific to you. Treatment outcomes vary between patients depending on individual circumstances.
References
Aligned with guidance from: NICE, FGDP(UK), SDCEP.