If the leftover bones are cooked, then it is not a good idea to give them to your dog to chew. If the leftover bones are raw, then it is a little bit safer to give them to your dog but raw bones still carry risks. Salmonella infections, obstructions, splintering injuries, and more can occur from raw bones, especially if they are too small. If you want to give your dog a bone to chew, make sure it's uncooked and at least the size of its head to decrease the odds of a dangerous piece getting broken off.