Can OP please provide the details of how their hand came to be in the proximity that allowed for said dog, with unknown previous interactions, to bite them? I don't usually make it a habit of placing my hands near the mouths of animals that I do not have regular familiarity with. I would be more embarrassed as a grown adult to admit I had engaged in such a seemingly careless act that resulted in my injury. If the dog had been running loose in the lobby or not under direct control of the owner then I apologize in advance as this is the result of an irresponsible dog owner.