Toothpaste that fills cavities is fake, toothpaste cannot fill cavities. Toothpaste can not repair cavities, hard tissues of the teeth produce cavities, can only go to the stomatology department in the dentist’s treatment can be repaired, toothpaste is unable to repair the hard tissues of the teeth. Toothpaste contains friction agents, wetting agents, sweeteners, surfactants, does not contain ingredients that can repair teeth. Toothpaste can only be used to clean teeth, which can prevent cavities from occurring and reduce the chance of them occurring. When there is a cavity produced, the doctor needs to perform decay removal, cavity preparation of resistant and retentive shapes, then disinfect the cavity, isolate it from moisture, and then fill the cavity, and finally adjust the grinding heights, polish and correct the shape. This is a process of filling the cavity. Maintaining good oral hygiene by practicing good oral cleaning habits can prevent cavities. It is recommended to seek medical treatment as soon as possible to prevent the cavity from expanding.