The Immaculate Conception - Is Mary Sanctified of Original Sin?

Even in the places where he explicitly states that Mary is not conceived without original sin, he's pretty clear in stating that she is. But even with that wrinkle, I think the one place in the sentences where St. Thomas most explicitly denies the Immaculate Conception, he says something to the effect of almost immediately after the installment, she would have been sanctified of original sin. The question of fittingness regarding Mary having any kind of a sin is clearly on the mind, even a bond of venture in Thomas.