Can gingivitis be passed on to others?

Perhaps you have a charming smile. It might be slightly crooked, showcasing your white teeth or even your vibrant red gums ... wait, red gums? Swollen, shiny, tender gums that bleed easily, along with mouth sores, are signs of gingivitis, not a healthy smile. Ignoring these symptoms can eventually lead to tooth loss.

Gingivitis is the initial phase of periodontal disease, a condition involving gum inflammation and infection. A significant portion of Americans—approximately 75 percent—experience some form of periodontal disease, though many remain unaware of it [source: University of Maryland Medical Center].

Gingivitis is particularly prevalent among individuals in their 30s and older, though it can start as early as the teenage years. The primary culprit? Plaque. Plaque is a sticky blend of food particles, bacteria, and mucus. When plaque and tartar accumulate on teeth over time, they irritate the gums. The bacteria in plaque release toxins, leading to inflammation and infection of the gums.

Your likelihood of developing gingivitis and other periodontal conditions increases if any of the following apply to you:

Genetics also significantly influence your susceptibility to gum disease. If you are genetically predisposed, your risk increases sixfold [source: American Academy of Periodontology]. Additionally, bacteria play a critical role. Studies indicate that family members and partners of those with periodontal disease face a higher risk, not solely due to genetics but because gingivitis-causing bacteria can be transmitted through saliva.

Bacteria's role in gingivitis

Our mouths host over 500 different species of bacteria. While most are harmless, certain types, such as A. actinomycetemcomitans and P. gingivalis, are known to heighten the risk of gingivitis and other periodontal diseases [source: Ciancio]. These harmful bacteria reside on our teeth, within gum pockets, and on the tongue. Unfortunately, we often share these bacteria with those closest to us, making it difficult to keep them to ourselves.

Although research is still in its early stages, studies indicate that individuals with periodontal disease can transmit disease-causing bacteria through saliva. Children under 3 years old are 26 times more likely to have A. actinomycetemcomitans in their mouths if their mothers carry the bacteria. Spouses are equally at risk, as multiple studies have shown that oral bacteria can spread through direct mouth-to-mouth contact. One study revealed that if one partner carries A. actinomycetemcomitans and P. gingivalis, there's a 20-to-30 percent chance of passing these bacteria to their spouse [source: Asikainen].

It's no surprise that periodontal disease, not cavities, is the leading cause of tooth loss among adults in the U.S. [source: American Academy of Periodontology]. However, the presence of gingivitis-causing bacteria doesn't guarantee gum disease. Factors like oral hygiene, lifestyle, health, and genetics—not just bacteria—play a crucial role in determining whether your gums will become infected.

If P. gingivalis takes up residence in your mouth, there's still hope: gingivitis is reversible. While antibiotics might seem like a solution, treatment typically involves scaling and root planing, which deep-clean the gums and control bacterial infection. Prescription mouthwashes and gels with antimicrobial ingredients can aid long-term management, and surgical options like flap surgery or bone and tissue grafting are available for severe cases.