Occurs when the extraction area fails to clot properly, thus causing a dry socket. I'm assuming you had all four of yours taken out so there's a slight chance you could have dry sockets in all four areas, although I seriously doubt it. I only had one thank God! Similiar to someone gettin' a scab on some place of their body, and they continue to pick at it making it much worse. You want all four extraction areas to clot b/c these clots actually protect the area underneath them and speeds up the healing process. If they fail to clot, then your extraction areas will hurt like a sum bitch due to the exposed nerve endings. Most of the time, dry sockets happen for no apparent reason. However, there are a few things that you should NOT do to lessen the risk of getting them: smoking, carbonated beverages, drinkin' through a straw, & try to cut out the spittin'....If you unfortunately think you have one, they usually start roughly 3 days AFTER you have them taken out.