Woman smelling her breath while looking in the mirror

Many Americans are by now well-acquainted with the abundance of information about the effectiveness of face masks in slowing the spread of COVID-19. Yet, while mask-wearing continues to serve as a protective measure against infection, some people’s first-hand experiences beg the question: What about what is happening under my mask?

Montry S. Suprono, DDS, MSD, director of LLU Center for Dental Research, explains what mask mouth is and how to prevent it.

Mask mouth: What it is and why it happens

Mask mouth refers to an array of adverse oral side effects people experience from wearing masks more often and for hours at a time. The main reason for mask mouth is that wearing a mask disrupts normal breathing patterns by hindering our ability to breathe through our noses. To compensate for this breathing resistance, we switch to breathing through our mouths.

The tendency toward mouth breathing is a primary cause of dry mouth, which occurs when you don't have enough saliva to keep your mouth moist. Saliva is a crucial player for many facets of oral health, from fighting off harmful bacteria to cleansing out food debris in your mouth. It also maintains acid/alkaline balance — pH balance — in the mouth, thus preventing tooth decay and gum disease. Also, the decreased saliva flow from dry mouth alters the oral microbiome — the bacteria habitat in the mouth.

Dry mouth, or xerostomia, heightens the risk for tooth decay and developing a slew of other undesirable conditions and symptoms, such as:

  • Tender gums (gingivitis) — Wearing a mask may impact the type and amount of bacteria in your mouth, causing plaque buildup that advances to your gum tissues. As a result, the gums are likely to feel tender and become red, swollen, or bleed easily during brushing and flossing. These symptoms are an indication of mild gum disease.
  • Persistent bad breath (halitosis) — Masks can trap the stench coming from the mouth. This is usually caused by a poor oral hygiene routine or eating smelly foods.
  • Fungal infections (candidiasis) — The combination of heat, humidity, and a tight mask could worsen underlying conditions that prompt a yeast-like infection. It manifests as a raw, red, irritated, or chapped area around your mouth.
  • Inflamed or irritated corners of the lips (angular cheilitis) — This is a type of fungal infection from harmful bacteria overgrowth under your mask that will appear as cracking, irritation, bleeding, and redness in the corners of the mouth.

Inhaling and exhaling under a mask can also deposit moisture and alter the flora on the outer parts of the skin and lips, leading to dermatological side effects like acne mechanica or "maskne.”

How to prevent it

Many tips for preventing mask mouth have to do with performing good oral hygiene care and keeping in good general health, as these two are interconnected. Suprono shares 10 measures you can take to avoid mask mouth:

  1. Brush regularly: Suprono recommends brushing your teeth at least twice a day, mainly after meals to remove bacteria and odor-causing food from your teeth and mouth.
  2. Floss daily: Sliding a cord of thin filaments between your teeth once a day, before bed if possible, clears food debris and plaque out from between your teeth in areas the bristles of a toothbrush can't reach.
  3. Add splashes of mouthwash: In addition to your brushing and flossing routine, you may use mouth wash once or twice a day to prevent plaque buildup and tooth decay. You might choose to use mouth wash in the morning or evening after brushing teeth or midday after a meal to freshen the breath and reduce bacteria. Avoid mouthwashes containing alcohol, as they will dry up the mouth.
  4. Chewing xylitol gum, or mints: While wearing a mask, it can be helpful to opt for chewing gum or eating mints that contain an ingredient called xylitol. The plant-based sugar helps stimulate saliva production, the strongest natural way to decrease acidity and raise low pH. Moreover, xylitol prevents cavities by inhibiting the growth of streptococcus mutans — the bacteria responsible for causing cavities.
  5. Limit sugary, caffeinated beverage intake: Be wary of consuming coffee, tea, or other sweet beverages like soda, as they increase acidity in the mouth. Plaque thrives off of acidity and can lead to an increased risk of cavities. If you drink any of these beverages, Suprono suggests chewing xylitol gum or mints or swishing water in your mouth. In addition, you may add some baking soda into the water to help increase your mouth’s pH.
  6. Hydrate hydrate hydrate: We tend to drink less water when we wear a mask, and it can further compound the effects of dry mouth. Regular water consumption is key to general and oral health, rinsing away harmful bacteria and food debris.
  7. Take mask breaks: If possible, take time to remove your mask from your face in a safe environment. Then, focus on breathing through your nose with your mask off.
  8. Subbing snacks: Instead of snacking on chips, cookies, and other processed whose sugar and carbohydrate content heightens the risk of cavities, try nuts instead. Raw, unsalted, and unflavored nuts like peanuts, walnuts, and cashews, provide a healthier alternative that increases saliva flow — not to mention their association with decreasing the risk of various chronic health conditions.
  9. Keep that mask clean: Exhaling and inhaling behind a mask for hours may deposit food particles and bacteria on the inside of the mask, where it collects and grows. Keep your re-usable masks clean by washing them at least daily, and throw away disposable face masks after a single-use, advises the CDC.
  10. Attend your regular dental checkups and cleanings: Keep up with your dental appointments every six months. Be sure to let your dentist know about your oral hygiene routine, raise any health concerns or new medications being taken, and share updates about your oral health.

When to make a dentist’s appointment

Sticking to regularly scheduled biannual appointments should significantly help you and your dentist keep abreast of any developing oral conditions.

If you have tried implementing the oral hygiene tips above and continue to experience sensitive teeth, bleeding gums after brushing or flossing, or feeling a toothache after eating something sweet, it may be time to call a dentist, Suprono says. When caught early on, changes in your mouth can be prevented or treated.

You can also schedule an appointment or request more information by visiting the School of Dentistry’s Faculty Dental Practice website or calling 909-558-4960.