Yes, but the in the cases I remember it was not on purpose.
1. When I was like hmm 5 yeas old maybe, I was sitting on the floor with a playful puppy and well I guess you know the teeth of puppies. sharp! and well, I got suprised when it wanted to play and scratched my hand.
we even have it on video 
2. My aunt and uncle's doberman. It was still a puppy, childish and clumsy, but it was bigger than the other older dogs!
.... Anyway ,we were both a bit clumsy and somehow our heads collided in a way that his tooth hit my face and gave me a nice bloody,and swelled scratch. 
But a cat did do it on purpose!
I was waiting for my grandmom who was talking to somone, so while waiting I thought I would join the cat in the bush next to us. I was patting it and my grandmom told me to be carefull, more than once i think... of course I was ..I thought!... it got tired of me, I guess, and scratched my arm.