Sure you can - I just prefer the white bread/milk combo. I met Celebrity Chef Michael Psilakis years ago and he said that Wonder Bread & milk are THE secret to his meatballs! It's referred to as a panade and adds a moist binder to the meatballs but keeps them tender. But breadcrumbs will work as well - you might need to add a little milk or a 2nd egg for the moisture.