Missing Teeth in healthy 4 yr old calico

I noticed that the tissue between my cat's nose and her upper lip was reddish/pinkish. Figured she got into something outside. There wasn't any blood or cuts so I left it alone. Two days later it looked fine, but I checked insider her mouth and it appears that all her little teeth are now missing. Her gums are a little pink but no evidence of blood or cuts that I can see. Her teeth are healthy as far as I know. Has anyone ever experienced this?