No, dogs cannot heal their wounds by licking them. Dog saliva does not provide any healing powers for its wounds. Again, the excess bacteria in the mouth can be more hazardous to the wounds. Often times, if a dog has a wound, it licks excessively, causing more problems, open sores and dermatitis. It is actually better to let wounds heal on their own and place an Elizabethan collar on your pet to ward off the licking until the area is healed. Remember, to always consult your vet immediately when it comes to any wound or injury to your dog.