Problem with my teeth??

I was looking at the back of my top front teeth with one of those dental mirrors, and the back of them looked kinda weird. i cant explain it well....but its as if a part of the back of the tooth is missing....like its not just a smooth backside of my tooth, its a little thicker in a little section of the tops of the back, but its most prominent on the 2 middle top teeth... i cant explain lol...can anyone look at the back of the top teeth like i did and sort of see what i mean? i hope i dont have a problem....i take decent care of my teeth
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If you cant explain it then how are we going to answer it?
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