I THINK I may have a cavity. I havent been to the dentist in well over 3/4 years. I've just now started being serious about my health. Today I was looking at my teeth , as I do almost ever 10 mins , and I decided to try to look behind my teeth. Everything was okay except on the two teeth beside my very front teeth , I noticed something black. Now when I brush my tongue against it, it feels like when something is stuck on your teeth. Only, I tried to pick it out but it still remains. So, this month I have to go to the doctor & eye doctor and wont be able to see a densist until well into next month. What can I do to make sure this doesn't get worse and to take care of it?