Well in there make up they are human like I mean. Molars, canines and such. Also say there teeth were formed of sugar it can get quite hard which could do some damage in this case.
I know yukkuri are generally presented as harmless to humans, but their teeth are similar to humans and humans can give a hell of a bite. I`m surprised you dont see more that with strays and such. Or hell even a rabid yukkuri there's an idea.