Your teeth...Not by looking at it with the naked eye...Looking at it microscopically...A teeth is like a square it has a top sideA, sides BC and bottom side D...Is the bottom i am talking about microscopically mapping your teeth the bottom of it....you may lose teeth, you may go to the dentist but still the same ridges microscopically at the bottom of your teeth will still be there...is like placing sand paper on your hand it will rub away your some of your palm fingerprints but there will be lots of markers still left there....

when i say the bottom i dont mean looking at it from outside through a 2 dimensional plane looking inside i mean looking from the bottom of the base looking upwards towards the few milimiters of width microscopically that the teeth is...Every human has a unique ridge of teeth...Dude fingerprints can be faked...

You know something else that is unique...if you was to make a map a microscopically matrix map and create logituded and latitude of the human hair and mantain a standard latitude/longitud matrix microscopically you could map the length of the pores that has the human hair...Think about it as trees every tree doesnt grow on the same location, same thing with the hair...