If a friend suffers from a disease that is contagious through sharing meals, he or she may be infected with the disease after tooth extraction; if a friend does not suffer from a disease that is contagious through sharing meals, he or she will not be infected with the disease after tooth extraction. If your friend suffers from a disease that is contagious through sharing utensils, such as Helicobacter pylori infection or viral hepatitis, the virus will enter the body through saliva and cause contagious diseases when a normal person gathers with his friends after tooth extraction. If a friend does not have an infectious disease, or if a friend has an infectious disease that is not contagious through sharing utensils, it will not be contagious, even if there is a wound in the mouth after the tooth is extracted. Therefore, if you are sure that your friend is healthy, it is safe to have a meal with your friend after a tooth extraction. If you suspect that you have a contagious disease after having a meal with your friends after a tooth extraction, you can go to the hospital for a checkup in a timely manner.