My dog has bad breath. What should be done?

As part of the yearly exam (or 6-month exam for elderly or sick dogs) the mouth should be examined along with all the major systems. This exam is part of medical data collection to facilitate good health in your dog. During this exam your veterinarian may find that there is something that indicates bad breath may be a medical issue (oral cancer, lung problem, heart problem, foreign body) or the exam may point at the mouth or teeth being dirty or problematic. The scope of this article is to explain how Astoria Animal Hospital approaches “smelly mouth” in dogs (and cats).

The mouth is generally a fairly dirty place. Whoever tells you that dogs’ mouths are cleaner than humans’ mouths is sadly mistaken. The mouth is an opening to the body where a lot of action takes place: eating, drinking, and breathing. Because of this the bacterial load is generally high. The bacteria swim in the moisture that is created by the salivary glands. The flushing action of the salivary gland fluid and the process of drinking water help minimize the bacterial load while dehydration (thirst) and eating tends to increase it.

When animals are young the salivary glands tend to produce saliva at a more frequent rate than older dogs (partly due to thyroid hormone which should be tested at least yearly in dogs over 6). Hence, older dogs tend to pack on the tartar quicker and more severely than younger dogs. Another reason older dogs tend to have more tartar is because they often have damage to teeth which provides a place where the bacteria/saliva combination called calculus can hold onto and grow.

Dental disease in dogs can be due to many things besides age. It can be due to mouth trauma (chewing on electric wires, being hit by car, falling out of a truck), misalignment of the teeth (overbite or under bite), poor tooth construction (tooth root malformations seen on dental x-ray), extra teeth (retained puppy teeth), cracked/fractured teeth (from chew toys, rocks, sticks). As you can see that the reasons for dental disease are many.

The effects of dental disease in animals, is also vast. The mouth is made of membranous tissue and is very vascular, and any breach in the mucous membrane (inflamed gums, broken tooth, exposed bone) can allow bacteria into the rest of the body. Bacteria in the system is called bacteremia. If there is bacteria in the blood it circulates and can settle into any tissue that has a blood supply, which is most tissues. It is thought that the most vulnerable tissues are the kidneys, the liver, the heart or the brain.

In order to get rid of the tartar on the teeth, a dental cleaning will be needed. It is recommended that a full exam/consultation take place prior to the dental cleaning as many things need to be discussed: financial cost, the dog’s anesthetic risk, extractions, and any work up that is recommended prior. In Oregon anesthesia-free dentistry is illegal for many reasons, so a discussion during this pre-operative exam regarding anesthetic is warranted.

All in all, to investigate “smelly breath” in animals one should (among many things) examine the mouth and the teeth. If you are worried about the breath, make an appointment with your veterinarian sooner rather than later to start collecting data regarding your dog’s health and learn if a dental cleaning may be needed.

Dr. Dannell Davis
Astoria Animal Hospital