Wolves clean their teeth on bones. Everyone knows that. Sharks just replace their teeth at a constant rate. Hey, maybe vamps do that too? Replace them?

I read a novel...I think the vamp brushed his teeth before going somewhere or other with the heroine (I don't think she knew he was a vamp at that point. Could be wrong on the exact details.)

I would think sipping or drinking blood would leave a horrible aftertaste, but yanno, not my thing.