Cracked teeth do not heal themselves. When a tooth is cracked, it should be treated as soon as possible according to the condition of the crack, and not wait for the possibility of self-healing, thus delaying the treatment. Cracks in teeth are related to factors such as brittle tissue, excessive biting force, accidental injuries and underdevelopment of tooth enamel. Slight hidden cracks will appear on the surface of the teeth when biting hard objects for a long time. Teeth with congenital enamel insufficiency or incomplete mineralization have a looser structure, and cracks or even chipping can also occur when subjected to greater biting forces. And after root canal treatment, the tooth loses its nutrient supply from the pulp, and the tooth tissue can become darker and brittle, making it susceptible to cracking or outright fracture. If the crack is deep and reaches the dentin layer, the tooth needs to be filled in time. If the crack is shallow, you can apply a layer of bonded composite resin and take care of it for regular restoration. If the crack reaches the nerve, root canal treatment is required.