Cracked tooth syndrome is defined as an incomplete fracture of the dentine in a vital posterior tooth. It can be caused by factors like occlusal trauma, restorative procedures, developmental defects, or parafunctional habits. Diagnosis involves examining the tooth for signs of cracking and reproducing the patient's symptoms. Treatment depends on the severity and location of the crack, ranging from restorations to root canal therapy or extraction. While cracks cannot heal, proper treatment can relieve symptoms and slow progression.