Epidemiological data reveals that as the improving of the oral health, morbidity rate of caries and periodontal diseases has decreased. Tooth fracture becomes a common cause of tooth loss in industrialized countries. Cracks and fractures can be classified as follows due to the extension and tissue involved: craze lines, fractured cusps, cracked teeth, split teeth and vertical root fractures. According to the pulp status and cracked extension, tooth fracture falls into two different types, which are incomplete tooth fracture and complete tooth fracture
of vital and non-vital tooth. Cracked tooth belongs to the incomplete tooth fracture of tooth with vital pulp. The cracked tooth with symptoms is called cracked tooth syndrome. This review focused on the clinical research about cracked tooth, which was providing thoughtway to diagnosis and therapy of cracked tooth.
