question: Hi i have a strange lump on the gum at the back of my mouth - my gum has been uncomfortable there for a while (few months) but I wouldn t say painful and lump is recent. When i pressed down on the top of it earlier this white stuff started coming through a hole at the side of the gum (facing into the mouth). It seems a little strange. My last tooth has always caused irritation at the back so i don t know if this makes a difference. I went to the dentist a couple of days ago and she took x-rays to check for tooth decay but everything was all okay and my wisdom tooth on that side showed up that it was still really embedded in the gum. I m not sure what this is and whether it is worth going back to the dentist??