Is a Dog’s Mouth Actually Cleaner Than a Human’s?

Dark-haired Pit Bull dog lies on its belly with its pink tongue hanging out while outdoors by a green plant

Picture this: you’re visiting a friend’s house for the first time. They have an exuberant dog who wants to slobber kisses all over you, perhaps even on your face. If you flinch away from these affections, chances are you might be told, “A dog’s mouth is ten times cleaner than a human’s mouth!” This saying is often bandied about, but is there any truth to it?

Comparing Apples & Oranges

While comparing mouths on a species by species basis is not completely impossible, a dog’s mouth and a human’s mouth are still really different—“like comparing apples and oranges,” according to Colin Harvey, former president of the American Veterinary Dental College. Both human and canine mouths are filled with microbes and bacteria. Although the germs in a human mouth might not always overlap with the kinds in a canine mouth, there are some commonalities.

  1. Gum Disease
  2. For example, gum disease (resulting in “dog breath” and tooth loss) is the most commonly diagnosed problem in dogs (and cats!). The Porphyromonas family of bacterium is the guilty culprit in causing gum disease in both humans and animals. P. gingivalis is the cause of human periodontal disease and its sibling P. gulae is the source in dogs.

  3. Tooth Decay
  4. Dogs are less likely to suffer from tooth decay than humans are. Cavities are often caused by the bacteria Streptococcus mutans, a kind of bacteria that feeds on sugar. Sugar is a lot more common in the human diet than the canine’s diet. Dog teeth are also differently shaped than ours. The pointy shape of dog’s teeth offers fewer places for food and bacteria to set up shop and damage the tooth’s structure. However, this does not necessarily mean that a dog’s mouth is cleaner than yours!

The Verdict

Let’s think about this question logically. Who brushes and flosses regularly? Who sees us at Bluedot Dental every six months for a cleaning and checkup? And who has been known to raid the garbage can and lick their bottom? Alas, it’s a myth: a dog’s mouth is not cleaner than yours. If you are a dog parent, don’t forget to care for your furry friend’s oral hygiene by brushing their teeth several times a week using the proper supplies and regularly visiting the vet.

Have a dental question for yourself, or need to schedule your own trip to the dentist? Contact us today!

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