do you have knowledge of geographic
tongue? they kind of resemble the patches in the
tongue due
to syphillis. Youmention that this patches cannot be removed, that is something good to know, because all of the patches or plaques taht happens in my tongue removes with food or brushing, and you can see the lost of papillae. More than withish plaques, they resemble grayish white.
hope your appreciation is correct, I actually never thought about this until I saw this pictures.