In that case, the teeth have to renew to some extent forever too, so that there is dental matter to rot for all eternity; and if they renew, it can't rightfully be said that they are rotting.
No a logrithmic slide into decay will do the job starting with the available teeth.
But there are "versions" of eternity where there is no birth, aging, illness and death, so most of what we usually think is "real" wouldn't apply there to begin with.
Sounds void to me.