sarah_c

I had a filling done on one of my upper left molars a few months ago, I noticed a lump developed immediatly afterwards just above the tooth but then it disappeared a few days later. Over the past few weeks it has come back, well at least I've only noticed it over the past few weeks because of the mild pain. Is this an abscess, is that serious, will the tooth have to be extracted now? Any feedback would be appreciated.