There is no bleeding. Do I still have to bite on the gauze?

Yes, even if you see no blood you should bite firmly on the gauze for at least 2 hours after an extraction. Even without visible bleeding, clotting is under way inside the socket, and pressure is needed for the clot to settle firmly. If a proper clot does not form, it can lead to a painful dry socket. If the bleeding has stopped after 2 hours you may take it out, and a slight trace of blood in your saliva is normal. However, if bright red bleeding continues even after changing the gauze, please come in.