Generally, teeth are very durable. They're designed to hold up to daily crunching, biting, and chewing of all kinds of solid foods. Sometimes, a one-off incident like a fall or impact to the mouth – or a chronic condition like nighttime teeth grinding – can generate enough force to crack or fracture a tooth. People with a history of tooth decay, large dental fillings, and root canal treatment may also be more susceptible to a fracture.

Contact your dentist right away if you think you already have a cracked tooth. If you want to avoid a cracked tooth, read on to learn the common causes of a cracked tooth and steps you can take to minimize your risk.

Common causes of a cracked tooth

A cracked tooth can be the result of many possible incidents. In some cases, you may have little idea what caused the fracture, especially if it happens overnight as a result of teeth grinding (bruxism) or if it forms gradually over time. The following are the most common causes of a cracked tooth:

• Teeth grinding: Chronic teeth grinding, also known as bruxism, can cause cracked teeth due to repetitive stress and friction. Since teeth grinding often occurs during sleep, you may not be aware it’s happening. These cracks may start out as minor stress fractures but can become more significant and painful over time if the cause is not corrected.
  
  
• Weak teeth: Weak teeth, whether from long-term erosion of enamel or lost tooth structure from large fillings, are far more susceptible to cracks. This is because the tooth structure can't withstand the normal rigors that teeth endure. Weak or eroded enamel can be a result of diet (acid drinks like soda), health conditions like acid reflux, and medications.
  
  
• Hard foods: Hard candies, ice cubes, and un-popped popcorn kernels are all frequent causes of cracked teeth. It’s not difficult to mindlessly bite into a piece of food at just the right angle to create a fracture. Chew slowly and navigate pitted fruits and similar food items with care.
  
  
• Accidental impact to the mouth: A direct hit to the mouth can cause chipped teeth, fractures, and other serious oral injuries. Most often these are the result of a sports incident, unexpected fall, or an auto accident. These types of tooth fractures may involve other complications: A blow to the mouth that causes a cracked, loosened, or knocked-out tooth should be considered a dental emergency that requires prompt attention.
  
  
• Extreme temperature changes: When tooth enamel is rapidly exposed to opposite temperature extremes – for example, immediately biting into an ice cube after burning your mouth on a hot drink – can lead to hairline cracks. This is because enamel expands and contracts during temperature changes.
  
  
• Age: With a lifetime of use comes weaker enamel and teeth more susceptible to injury. This is why older adults experience cracked teeth more frequently. To prevent cracks, worn-down enamel should be properly repaired or restored according to your dentist’s recommendation.

A cracked tooth is something dentists see regularly. If diagnosed early, the problem can usually be solved with a dental or endodontic procedure.

To prevent cracked teeth, be cautious when eating hard foods and chew slowly. If you grind your teeth, ask your dentist about a nighttime mouth guard for protection. If you play contact sports, wear a mouthguard. Take care of your enamel by avoiding sugary soft drinks and highly acidic foods and beverages. The stronger your enamel, the less prone your teeth will be to fractures. Get regular dental check-ups to make sure any potential problems are caught early on.

If you are experiencing pain on biting or chewing or increased sensitivity to temperature, you may have a cracked tooth. Do not ignore it. Make an appointment with your dentist to have the tooth evaluated and avoid further complications.