If your dog has bad breath, make sure he has had a thorough physical to rule out dental problems, such as periodontal or gum disease, which affect 80 percent of dogs over the age of three. In older dogs, an ammonia-like smell on the breath can indicate kidney disease. There's also a slight chance your dog has a mouth tumor or an infection that you can't see. Once you've ruled out any medical reason as the cause of bad breath, you can proceed with the following:
1. Brush your dog's teeth. Brush the front and back of your dog's teeth as you would your own for about 30 seconds on each side. If you start doing this early and regularly, before disease sets in, you'll save his or her teeth. For large breeds, try Benedent or Top Performance brushes. For small dogs, try Petrodex or Drs. Foster & Smith finger brushes. All four are widely available in pet stores or online.
2. If you can't get your dog to enjoy having his teeth brushed, give him a large hemp rope or rope toy to chew on—it acts as a sort of toothbrush, rubbing away food. (First soak the rope in beef broth.) Raw knucklebones are great for big dogs. Don't use them with small dogs who are not able to get their back teeth around the bone.
3. Cut your dog's facial hair. Keep your animal's hair trimmed and washed. Facial hair collects saliva and bacteria-causing odor around the mouth.