If your pet has horrible breath, one way to make it better is to brush their teeth. To brush their teeth, make sure you use a special pet toothpaste, not your toothpaste. Animals don't spit, and you don't want them to swallow the fluoride in your toothpaste. Also, pet toothpastes tend to have flavors that pets prefer (chicken, rather than mint). These procedures work best if you start as a puppy/kitten.

For a dog, use this procedure, building up over time:

1. Introduce them to the toothpaste either on a treat or let them lick it off the toothbrush every day for a week.
2. With your dog sitting, massage or gently stroke the cheeks for several seconds.
3. Starting with the upper lip, gently lift and pull back so they get used to be handled in this area.
4. Brush one upper tooth for several seconds rhythmically from gum line down toward the tooth.
5. Repeat for the lower lip/tooth.
7. Gradually increase brushing time to 1 minute.
8. To reach the surfaces of the teeth closest to the tongue, prop a toy between the teeth to hold the jaws open.
9. Praise them throughout the process.

For a cat, use this procedure, building up over time:

1. Massage the cat's cheeks for several seconds every day.
2. Introduce toothpaste by dabbing it on a treat and giving it to your cat.
3. Dab toothpaste on a small toothbrush and let your cat lick it off.
4. Dab toothpaste on a small toothbrush and put the toothbrush into your cat's mouth for a few seconds. Gradually increase to 15-30 seconds, without brushing.
5. Dab toothpaste on a toothbrush and brush one tooth in a slow rhythm from the gum to the tooth. Gradually increase to brushing several teeth.
6. Retract the lips creating a smile and brush the back molars. Gradually increase brushing time to a total of 1 minute.
7. If your cat tolerates only a short period of brushing, concentrate on upper, outer molars.
8. If your cat won't accept the toothbrush, try using a finger instead.