The Root of the Behavior
It is true that chewing on a bone does have some great dental benefits; it keeps your dog's gums and teeth clean. It is also true, however, that a bone that is too hard is one of the leading causes of broken or damaged teeth. Unfortunately, your canine may not have the ability to discern that the bone is the cause and continue to chew on them anyway, even while they are putting your dog in pain. The hardness is not the only concern bones can have for your dog. Some bones are more brittle than others and this leads to splintering. When a bone splinters, it can often create sharp edges that tear at the esophagus and stomach lining of your canine. This is the reason, for instance, that you are told never to give your dog chicken bones. Chicken bones are notoriously brittle and splinter very easily, however all bones can and do splinter to some degree or another. This could be the cause of your dogs pain.
Encouraging the Behavior
For instance, deer antlers are one of the best types of bones for your canine. They are very unlikely to splinter, provide great taste, and last a long time. However, they last a long time because they are rather hard in comparison to some other options out there. This hardness is likely to cause that dental damage in dogs that enjoy putting their full jaw force down onto that bone. Even still, the low rate of splintering makes it one of your better options. Speaking with your vet about your dog will give you a lot of insight into what choice is going to be best for you and your four legged friend.