Understanding and Preventing Mouth Sores

February 1, 2024 / Category: Dental Care

While those mouth sores might seem like no big deal, remember: they can affect anyone, and sometimes they’re warning signs of something more serious. Don’t ignore them! Understanding the type of sore you have is crucial, as different types will require different treatments to keep your oral health in tip-top shape.

Mouth Sore

Mouth sores are common, and can affect people of all ages. While many mouth sores are harmless, some indicate more serious problems. Treatment depends on the type of mouth sore you have.


What are mouth sores?

Mouth sores are painful lesions that form in your oral soft tissues. They may appear on your lips, gums, tongue, cheeks, the floor of your mouth or the roof of your mouth.

What are the different types of mouth sores?

The term “mouth sore” can describe a number of different conditions affecting the oral cavity. There are several types of mouth sores, including:

  • Canker sores: Sometimes called mouth ulcers, canker sores are one of the most common types of mouth lesions. These sores are usually red with white, yellow or gray in the middle. They’re not contagious, and they usually go away on their own in 10 to 14 days.
  • Cold sores: Also known as fever blisters, cold sores are caused by the herpes simplex virus. Unlike canker sores, cold sores are contagious and can be transmitted through kissing or sharing food and beverages.
  • Gingivostomatitis: This condition may be caused by a bacterial or viral infection, or it may be linked to poor oral hygiene. Gingivostomatitis is characterized by cold sores in the mouth — usually on the gums or inner cheeks. It’s most common in children.
  • Thrush: Also called candidiasis, thrush is a yeast infection inside the mouth. People with oral thrush develop white, creamy lesions on the tongue, cheeks and gums. While it’s unusual for thrush to be passed from person to person, it can happen — especially among immunocompromised individuals. Thrush is common among denture wearers (called denture stomatitis), but it can affect anyone.
  • Oral lichen planus: A chronic inflammatory disorder, lichen planus can affect your lips, cheeks, gums and tongue. You may notice raised, lacy patches of tissue. In some instances, you may have red, swollen mouth sores.
  • Leukoplakia: This condition causes thick, white patches to appear on the soft tissues inside your mouth. Leukoplakia is common in people who smoke. While symptoms usually go away on their own, more severe cases could be a warning sign of oral cancer.
  • Oral cancer: People with oral cancer may notice ulcers or red or white sores in the mouth. Unlike other types of mouth sores, lesions related to oral cancer don’t heal.

Who do mouth sores affect?

Mouth sores can affect anyone, but some are more likely to occur during a certain time in life. For example, while thrush and gingivostomatitis are most common in children, leukoplakia and lichen planus are more common in older adults.

What’s the most common type of mouth sore?

Cold sores and canker sores are among the most common types of mouth lesions. About 20% of people will develop canker sores at some point in their lives. And while over half of Americans have been infected with the virus that causes cold sores, only 20 to 40% of people develop cold sores as a result.

Symptoms and Causes

What are the symptoms of mouth sores?

Exact symptoms can vary depending on the type of mouth sore you have. In most cases, the lesions will cause redness, pain and inflammation. You may also experience:

  • Tingling or burning sensations.
  • Difficulty eating (especially spicy or salty foods).
  • Blistering.
  • Bleeding.
  • Ulceration.
  • Dysphagia (difficulty swallowing).

What causes mouth sores?

There are a number of things that can lead to mouth sores. Causes range from common injuries to serious health conditions. Common mouth sore causes include:

  • Biting your lip, tongue or cheek.
  • Irritation from braces or other orthodontic devices.
  • Brushing your teeth too hard, or using a hard-bristled toothbrush.
  • Using tobacco products.
  • Hormone changes.
  • Stress.
  • Burning your mouth on hot food.
  • Exposure to the herpes simplex virus.

There are also many diseases and health conditions that can cause mouth sores to develop, including:

  • Mononucleosis.
  • Celiac disease.
  • Anemia.
  • Folate deficiency.
  • Hand, foot and mouth disease.
  • Pemphigus vulgaris.
  • HIV and AIDS.
  • Lupus.
  • Crohn’s disease.
  • Irritable bowel syndrome (IBS).
  • HPV (human papilloma virus).

People who are undergoing cancer treatment may develop mouth sores as well. This is especially true for individuals receiving radiation therapy to the head or neck.

Are mouth sores contagious?

It depends on what type of mouth sore you have. Cold sores are contagious, but canker sores aren’t. If you’re unsure about the type of mouth sore you have, contact your healthcare provider.

How do mouth sores spread?

Contagious mouth sores — like cold sores caused by the herpes simplex virus — spread through saliva and close contact. If you think you have a cold sore in your mouth, avoid kissing and sharing food, beverages and utensils with others.

How long are cold sores contagious?

Cold sores are usually contagious for up to 15 days. When all symptoms have subsided — including blistering and scabbing — you are no longer considered contagious.

Are mouth sores viral or bacterial?

While viruses are the most common infectious cause of mouth sores, bacteria can cause oral lesions too. For example, cold sores are caused by the herpes simplex virus. But mouth sores like gingivostomatitis can be caused by certain bacteria, such as streptococcus and actinomyces.

What causes sores around the mouth?

Some sores only form on the soft tissues inside the mouth. Other sores — like cold sores caused by the herpes simplex virus — usually appear in the corners of the mouth or on the lips.

Diagnosis and Tests

How are mouth sores diagnosed?

Most mouth sores can be diagnosed with a visual examination. However, your healthcare provider may order a blood test or biopsy if your condition is severe.

Should I see a doctor or dentist for mouth sores?

In most cases, a dentist can appropriately diagnose and treat a mouth sore. However, if you have recurrent mouth sores that are associated with a medical condition, it’s best to see your primary care physician or an ear, nose and throat specialist.

How do I know if I have a mouth infection?

You can have a mouth infection without developing mouth sores. If you notice any other unusual symptoms, such as bleeding, swelling or tenderness, call your healthcare provider right away.

Management and Treatment

How do you heal a sore in your mouth?

Your healthcare provider may prescribe medication to ease your symptoms. Mouth sore treatments may include:

  • Steroid gel.
  • Pain relievers.
  • Anti-inflammatories.

Additionally, there are things you can do at home to reduce discomfort:

  • Rinse with warm saltwater a few times each day.
  • Take over-the-counter pain relievers, such as acetaminophen (Tylenol®) or ibuprofen (Advil®).
  • Avoid squeezing the sores.
  • Don’t smoke or use any other tobacco products.

What should I eat when I have a mouth sore?

When you have a mouth sore, try eating cold foods like sherbet, sorbet, ice pops or ice chips. This may help soothe the area. Avoid foods that are hot, spicy or salty — and steer clear of citrus-based foods like oranges, pineapple and tomato sauce.


Can mouth sores be prevented?

While you can’t prevent mouth sores altogether, there are some things you can do to reduce your risk. For example:

  • Practice good oral hygiene, and visit your dentist regularly.
  • Find ways to reduce stress, such as practicing mindfulness or meditation.
  • Eat a healthy, well-balanced diet.
  • Stay hydrated.
  • Avoid all tobacco products.
  • Use lip balm with an SPF of 15 or higher when outdoors.
  • Consume alcohol in moderation or avoid it altogether.

Outlook / Prognosis

What can I expect if I have mouth sores?

Most people who develop mouth sores experience no long-term effects. But some individuals notice that sores reappear from time to time. These outbreaks are more likely if you’ve been under stress or have a weakened immune system. If you have recurrent mouth sores, talk to your healthcare provider. They can determine if your lesions are related to an underlying condition.

Living With

When should I call my healthcare provider?

Not all mouth sores need immediate medical attention. But you should call your healthcare provider if you have lesions larger than a half an inch in diameter or if your mouth sore is accompanied by:

  • Fever.
  • Severe pain.
  • Sores or ulcers that haven’t healed after three weeks.
  • Blisters.
  • Skin rash.
  • Diarrhea.
  • Joint pain.

Additional Common Questions

Are cold sores a symptom of COVID-19?

While not a common symptom of COVID, mouth sores have been reported in people with the virus. More research is needed to determine if the oral lesions were caused by coronavirus or if they are secondary symptoms.


Most mouth sores are harmless, but they can be quite painful. Fortunately, treatments are available to help reduce discomfort. It’s important to have an evaluation with your healthcare provider if you have any unusual symptoms or if your mouth sores haven’t healed in three weeks. This can help rule out any serious health concerns and detect any issues early on.

Time to tackle those troublesome sores with Dr. Peter Abas. We offer general dentistry services and personalized care that last a lifetime. Schedule your appointment today at 949.586.1127. Join our IG community: @peterabasdds for more tips.

Reference: [https://my.clevelandclinic.org/health/diseases/21754-mouth-sore]