My little one had double teeth, too. I had read that it was somewhat normal for smaller breeds so wasn't surprised when I saw them. My breeder said they are called Gator teeth.... and she was right, that is exactly what they looked like. We ended getting them pulled when he was neutered (@ 8 months old) so we didn't have to put him under twice.
Also we had noticed horrible breath.... apparently was a rotten tooth (baby tooth) that didn't want to fall out. Once it was removed the foul order was gone.
Good luck with whatever you decide. I didn't know until reading this thread that they would sometimes fall out on their own. I thought they had to be pulled and I imagined he had discomfort in his mouth having 2 sets of teeth.
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