Is gingivitis contagious?

If you have gingivitis, your saliva contains bacteria that can be transferred to other people.
If you have gingivitis, your saliva contains bacteria that can be transferred to other people.
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Maybe you have a toothy grin. Maybe it's slyly crooked or shows off your pearly whites or your bright red gums ... wait, bright red gums? Bright red, shiny gums, swollen gums, gums that are tender when you touch them, bleeding gums and mouth sores are all symptoms of gingivitis, not of a pretty smile. And if these symptoms are left untreated, they can lead to tooth loss.

Gingivitis is an early stage of periodontal disease, an inflammation and infection of the gums. The number of Americans living with some form of periodontal disease is fairly substantial -- it's estimated that about 75 percent of us have a form of periodontal disease, though many aren't aware of it [source: University of Maryland Medical Center].


Gingivitis, specifically, is most common in the mouths of people in their 30s and older, but may begin as early as adolescence. The most common cause? Plaque. Plaque is a mixture of food debris, mucus and bacteria. Allowing plaque and tartar to build up long term on teeth irritates the gums, and the bacteria in plaque begins to produce toxins that cause the gums to become inflamed and infected.

Your risk of developing gingivitis and other periodontal diseases increases if any of these statements apply to you:

  • You have poor oral hygiene habits (both brushing and flossing are important).
  • You use tobacco products.
  • You have a poor diet or are malnourished.
  • You have diabetes or an illness that decreases your immune system function (such as HIV or cancer).
  • You are prone to clenching or grinding your teeth, or you are under stress.
  • You take certain medications (especially those that cause dry mouth).
  • You're female (it's the hormone fluctuations during puberty, pregnancy and around menopause that increase a woman's risk of gum disease).

Genetics also play an important role in whether or not you develop gum disease, and if you're genetically predisposed, your risk jumps six-fold [source: American Academy of Periodontology]. And then there's the role of that bacteria. Research suggests that the families and partners of people with periodontal disease have a higher risk of the disease, not necessarily because of the genetic link, but because gingivitis-causing bacteria is actually transferred among family members through saliva.


Bacteria's role in gingivitis

There are more than 500 different species of bacteria living in our mouths, and while most are considered friendly, there are a few types known to increase your risk of developing gingivitis and other forms of periodontal disease, including A. actinomycetemcomitans and P. gingivalis [source: Ciancio]. This injurious bacteria lives on our teeth, in the pockets of our gums and on our tongue. And as it turns out, we're not very good at keeping our bacteria to ourselves, at least when it comes to those closest to us.

While research is still preliminary, studies have found links suggesting that people with periodontal disease pass along the disease-causing bacteria through saliva. Children under the age of 3 years are 26 times more likely to test positive for A. actinomycetemcomitans in their mouths if their mothers test positive for that bacteria. And spouses are no safer from transmission than kids. Multiple studies have found oral bacteria transmission through person-to-person, mouth-to-mouth contact, and one study specifically showed that if one spouse is colonized with A. actinomycetemcomitans and P. gingivalis, that spouse has a 20-to-30 percent likelihood of passing that bacteria on to his or her partner [source: Asikainen].


It's no wonder that periodontal disease, not cavities, is the No. 1 cause of tooth loss among adults in the U.S. [source: American Academy of Periodontology]. The good news, though, is that if you have gingivitis-causing bacteria in your mouth, it doesn't guarantee that you'll develop gum disease. Other factors such as oral hygiene habits, personal habits, health and heredity -- not just bacteria alone -- determine whether or not your gums will become infected.

And if your mouth does become home to P. gingivalis? More good news: Gingivitis is reversible. Because periodontal disease is caused by bacteria, you might want to reach for antibiotics to kill the disease, but treatment most frequently consists of a process called scaling and root planing, two therapies that help control the bacteria and infection and deep clean the gums. Prescription medications such as mouthwashes and gels that contain antibiotics and antimicrobial ingredients may help with long-term disease control, and there are also surgical treatments available for treating persistent or severe disease, including flap surgery (the deepest gum-cleaning therapy) and bone and tissue grafting.


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More Great Links


  • American Academy of Pediatric Dentistry. "Policy on Early Childhood Caries (ECC): Unique Challenges and Treatment Options." 2011. (Sept. 16, 2011)
  • American Academy of Periodontology. "Fallacies About Gum Disease." (Sept. 16, 2011)
  • Asikainen, Sirkka; Chen, Casey; Alaluusua, Satu; and Jørgen Slots. "Can One Acquire Periodontal Bacteria and Periodontitis from a Family Member?" The Journal of The American Dental Association. Vol. 128, no. 9. Pages 1263-1271. 1997. (Sept. 16, 2011)
  • Ciancio, Sebastian and Fontinos S. Panagakos. "Superior Management of Plaque and Gingivitis Through the Use of a Triclosan/Copolymer Dentifrice." Journal of Clinical Dentistry. Vol. 21, special issue. Pages 93-95. 2010. (Sept. 16, 2011)
  • National Center for Biotechnology Information, U.S. National Library of Science. "Gingivitis." 2010. (Sept. 16, 2011)
  • National Institute of Dental and Craniofacial Research. "Periodontal (Gum) Disease: Causes, Symptoms, and Treatments." 2010. (Sept. 16, 2011){CE246689-D899-4CC7-B68A-805AD910F4E7}&NRORIGINALURL=%2fOralHealth%2fTopics%2fGumDiseases%2fPeriodontalGumDisease%2ehtm&NRCACHEHINT=Guest
  • Tribble, Gena D.; Lamont, Gwyneth J.; Progulske-Fox, Ann; and Richard J. Lamont. "Conjugal Transfer of Chromosomal DNA Contributes to Genetic Variation in the Oral Pathogen Porphyromonas gingivalis." Journal of Bacteriology. Pages 6382-6388. Sept. 2007. (Sept. 16, 2011).
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  • WebMD. "Oral Health Center -- Gingivitis and Periodontal Disease (Gum Disease)." 2009. (Sept. 16, 2011)