I have developed a black section on my gum. It is located on the lower interior and covers the back section of my gums on one side and has made my gums recede away from my crowns. It is not painful but the front side of that same section is sore; feels like there is a coating on my gum and hurts to brush on that side. There is no coated feeling where the black is located. Several dentists have looked at this and say they have never seen anything like it and have no idea what it is.
I can't find any information on this so if anyone has experienced this, please tell your experience. Thanks!