<s>[INST] My nephew is teething and today we found extra skin in his mouth that was black. When we checked later a tooth had broken through and the black was gone, but now there is more skin on the bottom left gum, it is not a blister but more of a lump or a big ball of skin. What could this be? [/INST] Hi... Thank you for consulting in Chat Doctor. Skin conditions are best diagnosed only after seeing directly. I suggest you to upload photographs of the same on this website, so that I can guide you scientifically.  Hope my answer was helpful for you.  I am happy to help any time. Further clarifications and consultations on Chat Doctor are welcome. If you do not have any clarifications, you can close the discussion and rate the answer. Wish your kid good health. </s>