All of our yorkies were using the pee pads and had an occassional one that would be torn or they might decide to play with it. When the Biewers came, Leo and Hannah thought it was a riot to play tug of war with them and I was constantly cleaning them up.
One of the threads here at YT mentioned washable pads with a website
http://valethics.com I've ordered three different shipments of them and plan on using them in the whelping beds this next month (we've got three litters due). Wish I'd found them sooner.