My Kissy has the underbite and she has a bigger lower lip which makes it really cute, IMO!
I had to have several of her permanent teeth removed on top to allow her bottom canines to come in straight. She has perfectly straight teeth now and there is a little gap on top on both sides that allow her bottom canines to go up. If we hadn't had this done, her teeth would have collided and she may have ended up with the bulldog look where their teeth bow out on the sides.
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