Most common mouth sores, such as canker sores and cold sores, will appear on the gums, cheeks, or lips. In some cases, they may appear on the roof of the mouth. Sores can cause pain, blisters, and swelling. Some people may notice pain or swelling before the sore appears.

 

2. Injury or trauma

One of the most common causes of swelling on the roof of the mouth is an injury or trauma. Some of the most common causes of trauma include:

• eating a hard food that may impact the roof of the mouth
• eating or drinking an extremely hot item
• a scratch from a sharp piece of food

3. Dehydration

Dehydration can cause swelling on the roof of the mouth. Dehydration can cause a dry mouth, which can result in swelling if a person does not take steps to relieve the condition.

Some common causes of dehydration and dry mouth include:

• excessive alcohol intake
• certain medications
• not drinking enough water
• excessive sweating, particularly on hot days or while exercising
• illness

A person with dehydration that causes an electrolyte imbalance may also feel especially weak or experience muscle spasms.

4. Mucoceles

A buildup of mucus can form inside a lumpy cyst that appears on the roof of the mouth called a mucocele. Mucoceles are typically painless and usually occur after a minor injury, such as a cut on the roof of the mouth.

They do not usually require treatment and may burst on their own. If a person has a mucocele that is particularly large or tends to recur, a doctor can safely drain it.

5. Squamous papillomas

The human papillomavirus (HPV) is responsible for the formation of squamous papillomas. Squamous papillomas are noncancerous masses that can form on the roof of the mouth.

These masses do not typically cause pain. However, once discovered and diagnosed, people should get them treated. It is possible that a doctor may need to perform surgery to remove the mass.

6. Underlying medical conditions

Rarely, a swollen roof of the mouth may be due to an underlying medical condition, such as oral cancer or viral hepatitis.

Oral cancer is uncommon. According to the American Cancer Society, approximately 51,540 people in the United States will receive an oral cancer diagnosis in 2018.

Treatment and home remedies

In most cases, a person can treat a swollen roof of the mouth at home or wait for it to heal on its own. Common injuries, such as a burn from a hot drink, will typically heal within a few days.

Cold sores or canker sores usually go away on their own. In some cases, a person may wish to use medications to help reduce the frequency or severity of cold sores. In cases of dehydration or electrolyte imbalance, people can increase their liquid intake. It is best to drink non-alcoholic beverages, such as water or herbal tea.  If electrolytes are too low, a person may consider drinking a sports drink or juice to help restore the balance.

In cases where a person has an underlying condition, they should seek medical help from a doctor. Treatment options for cancer can include surgery, radiation, or chemotherapy.