The most common cause of a cracked tooth is a sudden external aggravation of a single tooth, such as biting into broken bone or stone particles, where the patient often feels significant pain and is then afraid to chew.
This condition can also occur after root canal treatment, as the tooth loses its elasticity due to the loss of blood nutrient supply, and teeth that have not been restored with a crown are prone to fracture when exposed to excessive cold, heat or large biting forces.
This condition can also be seen in teeth with significant tooth defects in the neck of the tooth caused by horizontal brushing, acidic environments in the gingival sulcus, and stress concentrations, resulting in a lateral cracking of the tooth.