Fish oils help with the coat. You can add Cod Liver oil, I think it is a teaspoon per day rizzled over the dry kibble. OR you can buy it in this pockets, you squish it open over the food.

On the tooth question: do you give them hard chews? Will they take carrots to crunch instead? One of mine -Sugar - LOVES her carrots, and Lacey eats them because Sugar does.