It is normal for yorkies to retain puppy teeth. Two of the three of mine had at least one puppy tooth that was retained. Pebbles was a puppy and had 2 removed during her spay. The only problem was that one was right in front and now she has a gap were the baby tooth was remove. Bogey was over a year and since he was a rescue his was removed during his neuter. Prior to is being removed he had very stinky breath but the removal of the puppy tooth had an immediate difference in his breath.
Talk to your vet about having any puppy teeth removed during spay/neuter. Leaving them in can cause more harm than good.
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