As puppies teeth, they like to chew on things to help massage their sore gums. Furniture legs, door trim casings and baseboards often bear the chew marks of a teething puppy. If your dog has chewed all the way through a piece of wood, you can't do much to fix it, other than replace the destroyed section. But, if the wood has only minor damage, you can repair it with wood putty.
Scrape all large splinters off the damaged wood with a putty knife.
Sand the chewed area with a piece of 80- or 100-grit sandpaper. Fold the sandpaper in half to give yourself a better grip.
Dust the sanded wood by wiping it down with a clean cloth.
Fill the chew marks with wood putty using a putty knife. Overfill the chew marks a little to make up for the shrinkage that will occur as the putty dries.
Wait 24 hours. Then, sand the putty and the surrounding wood surface with 150-grit sandpaper until smooth.