Well this is an interesting question and the result is variable to be honest.
The flipside is that there will always be some women who feel very little after breast reduction surgery.
Breast and nipple sensation varies from patient to patient, but in my hands, most girls and women can actually feel the cold wash as I inspect the scars and nipples at week three. This is often a surprise to them, but from that moment on, more and more comes back. You might notice cold and touch to start, then more sensation returning over the next few weeks and months.