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Germs Quiz: What Lives in Your Mouth?

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The number of bacteria in your mouth is closest to the population of which of the following?

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The number of bacteria in your mouth is closest to the population of which of the following?

  • Your Answer:
  • Correct Answer:

A typical human mouth contains billions of bacteria. If you haven't brushed your teeth lately, you might well have more bacteria in your mouth right now than there are people living on planet Earth. Scientists have identified more than 700 different species of mouth-dwelling microbes.

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A dog's mouth is cleaner than a human's.

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A dog's mouth is cleaner than a human's.

  • Your Answer:
  • Correct Answer:

There's no basis for concluding that a dog's mouth is "cleaner" than a human's. Both humans and dogs have mouths that are full of bacteria, and both contain roughly the same number of bacteria. And there are more than 100 different germs in dog (and cat) saliva that can make you sick.

If you drop food on the floor, it won’t pick up any germs if you pick it up within 5 seconds.

If you drop food on the floor, it won’t pick up any germs if you pick it up within 5 seconds.

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While it’s true that the longer food is on the floor, the more germs it will pick up, the “5-second rule” is arbitrary. Food starts to pick up germs from the moment it hits the floor. You’re better off tossing it and eating something else.

Anyone who kisses someone with gum disease will always get it.

Anyone who kisses someone with gum disease will always get it.

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  • Correct Answer:

Periodontal disease is not contagious. While bacteria that lead to gum disease can pass through saliva, gum disease typically develops if your teeth and gums aren’t healthy. If your mouth is not healthy, you increase your risk through repeated and prolonged exposure to someone with periodontal disease. The American Dental Association recommends brushing twice a day and flossing daily.

If you find yourself without a toothbrush, it's a good idea to borrow a friend's.

If you find yourself without a toothbrush, it's a good idea to borrow a friend's.

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  • Correct Answer:

You should never share a toothbrush with someone else. The CDC advises that "the exchange of body fluids that such sharing would foster places toothbrush sharers at an increased risk for infections."

Which of the following items can transfer potentially dangerous microbes between people?

Which of the following items can transfer potentially dangerous microbes between people?

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  • Correct Answer:

Studies have demonstrated that germs may be present on lipstick (including “tester” lipstick at cosmetics counters), lip balm, drinking glasses, band instruments, and many other items that may sometimes be shared.

 

Don't share such personal items if you want to avoid picking up potentially harmful bacteria, viruses, or other microbes.

To protect your toothbrush from harmful germs, you should:

To protect your toothbrush from harmful germs, you should:

  • Your Answer:
  • Correct Answer:

The American Dental Association recommends rinsing your toothbrush with tap water after you use it, then letting it air-dry. Keeping it in a closed container creates an ideal moist environment for the growth of bacteria.

 

According to the ADA, "there is no clinical evidence that soaking a toothbrush in an antibacterial mouth rinse or using a commercially available toothbrush sanitizer has any positive or negative effect on health." And using a dishwasher or a microwave could damage your toothbrush.

 

Experts recommend following similar advice for retainers or other dental devices that you put in your mouth, although additional disinfection with a denture cleanser may be recommended. Ask your dentist about the proper way to care for any particular dental devices that you may be using.

To avoid the buildup of bacteria, the American Dental Association recommends replacing your toothbrush every month.

To avoid the buildup of bacteria, the American Dental Association recommends replacing your toothbrush every month.

  • Your Answer:
  • Correct Answer:

The American Dental Association recommends replacing your toothbrush every 3 to 4 months, sooner if the bristles are frayed. The ADA’s main reason for replacement is to make sure your toothbrush is in good working order -- not because of bacteria. Although the group acknowledges that "various microorganisms can grow on toothbrushes after use," they maintain that there is "insufficient clinical evidence to support that bacterial growth on toothbrushes will lead to specific adverse oral or systemic health effects."

Antiseptic mouthwashes can kill the germs that cause bad breath.

Antiseptic mouthwashes can kill the germs that cause bad breath.

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  • Correct Answer:

Antiseptic mouthwashes do more than keep your breath fresh. The American Dental Association says they help reduce the film of bacteria that forms on teeth (plaque) and gum inflammation (gingivitis). Many dentists recommend rinsing with an antiseptic mouthwash twice a day to help keep your teeth and gums healthy. Of course, bad breath can be caused by things other than germs, such as eating garlic or other fragrant foods, or poor dental hygiene. Certain medical conditions also can cause bad breath. In these cases, a mouth rinse may help mask your bad breath, but it won't address the cause of it.

Drinking green tea may help keep your teeth and gums healthy.

Drinking green tea may help keep your teeth and gums healthy.

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Research indicates that green tea has been associated with healthier gums and lower odds of tooth loss.

All bacteria are bad for the health of your teeth and gums.

All bacteria are bad for the health of your teeth and gums.

  • Your Answer:
  • Correct Answer:

While some bacteria are bad for your teeth and gums, others are critical to keeping them healthy. In fact, some helpful organisms in your mouth secrete substances that kill bad bacteria. Researchers are exploring a potential new kind of toothpaste based on a mouth bacterium that creates enzymes that prevent plaque formation.

Most bacteria in your mouth reside in plaque.

Most bacteria in your mouth reside in plaque.

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  • Correct Answer:

Most of the bacteria in your mouth are part of a sticky film on your teeth known as plaque, which is the main cause of tooth decay. A single tooth can host 500 million bacteria. This is, of course, why you brush your teeth, floss, and use an antiseptic mouth rinse.

Bacteria in your mouth can cause tooth decay by:

Bacteria in your mouth can cause tooth decay by:

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  • Correct Answer:

When you eat, the bacteria on your teeth excrete acids that can weaken tooth enamel. This is why it’s better for your teeth to confine eating to larger meals, rather than snacking throughout the day; the more times you eat, the more times the bacteria on your teeth will release their damaging acids. Fluoride toothpaste and other fluoride products, like mouth rinses, help strengthen enamel and prevent cavities.

Research has shown a link between gum disease and:

Research has shown a link between gum disease and:

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  • Correct Answer:

Harmful bacteria in your mouth can lead to gum disease, which has been linked with a number of other chronic inflammatory diseases throughout the body such as diabetes, cardiovascular disease, and Alzheimer's disease. It was once believed that the bacteria were the culprit. But researchers have begun to believe that the resulting inflammation is the key.

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Good job! You know how to deal with those germs in your mouth.

Not bad, but you can do better. Brush up on the germs in your mouth and try the quiz again.

Keep trying. Brush up on the germs in your mouth and try again.

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