Canker Sores on Roof of Mouth: Causes & Treatment

Canker Sores on Roof of Mouth: Causes & Treatment

 Whitney DiFoggio MA, RDH
Written by Whitney DiFoggio MA, RDH
Medical Reviewed on Oct 17, 2023
byDr. Matthew Hannan DDS
🔬 Evidence Based
Canker Sores on Roof of Mouth: Causes & Treatment

When most of us get an ulcer or canker sore in our mouth, it’s usually on the inside of our lips or cheeks. Sometimes we even notice them in the floor of our mouth or under our tongue. A canker sore on roof of mouth surfaces (aka your “palate”) can’t be ruled out, but they are less common.

The only difference in a canker sore on the roof of mouth tissues vs. other places in your mouth is that the surface doesn’t “move around” the way the gingiva on your lips, cheek, or tongue does. It’s attached to a fixed, bony base (your palate) instead of an area with muscles underneath.


The first thing you’re probably going to notice if there’s a new canker sore on roof of mouth/palate areas is tenderness when you’re swallowing. We swallow all day long, even when we’re not eating or drinking. Each time your tongue presses up against your palate, it can irritate the ulcer that’s there. And if you are eating, there’s likely to be even more irritation to that delicate area of skin.

Depending on the type of ulcer that you have (canker sores are just one form of lesion) you might notice small clusters of blisters, a smooth raw area, ulcers in other parts of your mouth, or even a riveted area that looks like a crater in your mucosa (oral skin.) Some have prominent red margins. As your ulcer starts to heal, you’ll likely see a whiteish coloration across the surface. Herpetiform ulcers (like those linked to cold sores) typically start out as a visible blister but gradually take on a caved-in appearance. But when the roof of your mouth is involved, there’s not much room for a sunken-in surface, so the sore may seem smooth like other canker sores.

Ulcers and canker sores tend to hurt consistently, even if you’re not touching them. Generally, the average lesion will be evident for about 10-14 days. Constant irritation or a major canker sore can add to your recovery time.

How To Treat A Canker Sore (Ulcer) On Your Palate 

Most oral sores — whether they’re cold sores, fever blisters, aphthous ulcers, or canker sores — are treated the same way: through self-care at home.

1) Leave It Be

First and foremost, try to avoid any unnecessary stimulation to that area. Since the outermost layer of tissue over the sore is thin and delicate, irritation can cause pain and delay the healing process. That means don’t scrub it with a toothbrush or rub the area with your tongue (while you’re trying to “feel” it). You can brush your teeth, but just take care to not touch your toothbrush to that general area. If it’s close to a tooth, avoid brushing that specific spot as the ulcer heals.

2) Modify Diet

Second, alter your diet temporarily. Avoid acidic or hard foods, such as tomato sauces/soups, tortilla chips, etc. Physical stimuli can irritate sores in your mouth, causing pain or even additional damage to that area. Instead, opt for cool soft foods such as yogurt, cottage cheese, gelatin, smoothies, etc. After a few days you can graduate from a soft diet to firmer foods. Just play it by ear.

3) Be Proactive 

Finally, if you have a severe ulcer, cold sore, or are prone to frequent flare-ups, talk to your dentist. They may be able to prescribe a medication that shortens the duration of your ulcers or even utilize laser therapy to treat active lesions. If it’s a medication that they prescribe, go ahead and use it as directed as soon as symptoms start to pop up. In-office laser ulcer therapy can speed up the recovery process, reduce sensitivity, and shorten the lifespan of sores like fever blisters by up to 50%; the key is to get in touch with your dentist as early as possible.

Your dentist can prescribe a “miracle mouthwash” if your canker sores are severe. Although the medication doesn’t treat the sore per se, it does help to get you out of pain enough so that you can get through your day-to-day activities like eating and drinking.

Home Remedies

In most scenarios, a canker sore on roof of mouth tissues can be treated at home. Rest and attentiveness to irritation are key. You’ll want to be sure to stick to a soft diet, stay hydrated, and minimize consuming any acidic liquids (which may burn or sting.)

Keep your mouth clean of food debris and bacteria to aid with healing. Even though you don’t want to use harsh mouthiness or clean that space with a toothbrush, you can rinse regularly with saline or lukewarm saltwater, which will also help with inflammation. If the ulcer is near a tooth and you’re not able to brush that area, be sure to rinse at least a few times per day.

Over-the-counter numbing medications such as sore throat sprays and teething gel can offer temporary relief when used as directed. Do not use those products for more than a couple of days. Clove oil is a good substitution for topical numbing gel and can be applied with a cotton ball or Q-tip.

And finally, taking a non-steroidal-anti-inflammatory (NSAID) medication like ibuprofen will help with pain and inflammation as your body heals. Only take the medicine as directed and call the dentist if you need it for more than a couple of days.

Cause Of Canker Sore

There are dozens of factors that can cause ulcers or canker sores to pop up in your mouth. According to Mayo Clinic, here are some of the most common factors:

  • Traumatic injury to a specific part of your mouth (like slipping with your toothbrush or biting your cheek)
  • Specific types of toothpaste ingredients, such as sodium laurel sulfate
  • Food sensitivities
  • Deficiencies in vitamins B-12, folic acid, zinc, and iron
  • Hormonal changes
  • Stress
  • Celiac disease
  • IBD (including ulcerative colitis and Crohn’s disease)
  • Behcet’s disease
  • Immune deficiency

We also know that specific viral strains can lead to ulcers in your mouth, such as the herpes virus responsible for chicken pox and shingles. There’s also new research that suggests people with the novel coronavirus can exhibit symptoms of mouth ulcers and sores.

Depending on the cause of your canker sores, it may be that the mouth ulcers pop up because of irritation to that area of your palate, or due to an underlying risk factor. Understanding the oral-systemic balance of medical issues as they relate to your mouth can help you on your way to better overall wellness as well as controlling recurring oral ulcers. It might even be a great warning sign that alerts you to your body going through a period of stress, an upcoming IBD flare-up, or that your immune system needs some good old-fashioned R&R.

Complications With Orthodontic Appliances

People who wear braces may tend to notice canker sores just next to areas where their bracket or wire rubs against their mouth. But braces can’t cause canker sores in the roof of your mouth. The only exception might be if you have lingual braces, a palatal expander or removable retainer that rubs the roof of your mouth or traps food underneath. Work with your dentist or orthodontist to make sure you’re able to keep that area clean and free of debris.

When To See A Doctor

Most ulcers and canker sores heal on their own. Time and treating that area with a delicate hand ensures a proper healing process. However, complications such as infections or repeated trauma to a canker sore can lead to unwanted side-effects. And in limited circumstances, the sore could be attributed to something life-threatening like oral cancer.

NOTE: If you have ulcers, fever blisters, or canker sores on the roof of mouth that haven’t healed within 10-14 days, you need to seek out the opinion of an oral health professional. Your dentist will evaluate the area to determine if something abnormal is going on. Usually they will re-evaluate you a couple of weeks later and then order a biopsy of those tissues if they still haven’t healed.

How To Prevent Canker Sores 

If you’re someone that gets canker sores frequently, a bit of investigative work can help you pinpoint your “triggers.” That is, certain factors that may cause you to get ulcers more often. We know that being ill, immunocompromised, stressed, or sun exposure can be a trigger for some people to get canker sores. That’s why “fever blisters” tend to flare up when you’re coming down with a bug, so to speak.

To boost your immune system, eat a balanced diet that’s rich in nutrients and vitamins. Supplement with a multivitamin as needed. Getting plenty of fresh vegetables, vitamin D (from the sun - in moderation of course!) and exercise can boost your immunity and help your body respond quicker to illnesses more effectively.

Take care when you’re brushing and eating to not accidentally poke or hurt the roof of your mouth. Brushing too hard/quickly or taking large bites of hard foods (like tortilla chips) can increase your chances of oral trauma, which then leads to canker sores.

And finally, if you’re in orthodontic appliances or prone to ulcers, have the right tools on hand, such as orthodontic wax or your prescription medication.

Overcoming Canker Sores On The Roof Of Mouth

Are you prone to ulcers, canker sore on roof of mouth flare-ups, or fever blisters? The average canker sore is usually caused by irritation or immune responses. Treating the area delicately is usually all you need to do for the sore to heal on its own. See your dentist if the ulcer starts to get infected or hasn’t healed within two weeks. As long as you can eat or drink comfortably, at-home treatment is usually all that’s required.

 Whitney DiFoggio MA, RDH
Written by Whitney DiFoggio MA, RDH"Teeth Talk Girl," is a registered dental hygienist. She started her dental health journey on YouTube, educating the public through videos.
Dr. Matthew  Hannan DDS
Medical Reviewed byDr. Matthew Hannan DDSDr. Matthew Hannan is a board-certified dentist and graduate of UT Health San Antonio School of Dentistry.
Last updated onOctober 18, 2023Here is our process

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