It looks like this tooth in the picture here: leftmost tooth on the top (this is from a different yorkie; I can't imagine Cookie letting me take a pic of her mouth):
http://steventyler.files.wordpress.c...1/img_0899.jpg
There is definitely a tooth growing inside of there, but it's much smaller. The smaller one on the inside is the permanent tooth and the loose one on the outside is the baby?