<s>[INST] I had a wisdom tooth removed about a year ago and its been fine but recently I feel like the hole opened up.  Its sore and feels like hamburger. I don't know what I did but chewing back there on accident makes it worse. I started swishing with salt water last night. Any advice? [/INST] Hello, Thank you for consulting with HCM.As you are mentioning that you got your wisdom tooth removed about 1 year ago, in that case the hole should not open again as the tooth is missing. But it can be possible that the tooth adjacent to the wisdom tooth might have become carious and now because of the infection of the root area , there is pus collection in gums which is now discharging  from the gums.Or it can also be possible that there is a traumatic ulcer in the gums.For confirmation of diagnosis you have to visit a dentist and get an x-ray done of that area which will show the infection. And treatment will done accordingly.Hope it will help you. </s>