Gum or bone growth?

[Jenninewell05]

I have what seems to be my gums (right below my gum line) or lower jaw growing in towards each other (nearly touching between my lower teeth). It has been this way for years with no pain, teeth, or gum problems. It is very hard like it was bone covered with skin. It didn't bother me until now when I noticed that the same thing is happening on the outside (cheek side) of my gumline on one side, but not the other. I have no pain. I have looked for hours on the internet and cannot find anything close to resembling what this is. I know I need to see a dentist, but would like to have some idea of what this is before I go.

[Gellia]

Hi,  Is it possible it is plaque that has collected there?  I never had any problems with my gums bleeding at all or any cavities but found that there was alot of bone loss in my teeth because of plaque buildup around the tooth root and down in the gums.  
I went to my periodontist and had to have deep root planing and scaling.  Please go to your dentist and see if it that may be it.