Bite the cotton after tooth extraction time is generally recommended in 30-40 minutes or so, to play the main role of compression hemostasis, normal in the extraction of traumatic teeth, extraction after the extraction of trauma will have the normal phenomenon of blood seepage. The oozing blood will form a more perfect blood clot in 15-30 minutes, and during this period of time, it is recommended to apply cotton balls or cotton rolls to press on the original extraction wound, and ask the patient to bite tightly so as to play a localized compression effect of hemostasis. It is not recommended to brush teeth, rinse mouth, lick the extraction wound with tongue, or suck the extraction wound within 24 hours after tooth extraction, in order to prevent the dislodging of blood clot in the extraction wound, which will cause secondary bleeding.