Mouth Sores, Bumps & Patches: A Guide to Oral Lesions
Found something in your mouth that wasn't there yesterday? Start here. This guide covers the mouth sores, bumps, white patches, red spots, tongue changes and sore gums people search for most, with plain-English explanations, home care, and honest advice on when it's worth having it looked at.
Most sores, bumps and patches in the mouth have everyday causes: a bite or scrape, a canker sore, the cold sore virus, a yeast infection (thrush), rubbing from a sharp tooth or denture, or normal anatomy you just noticed. Less often they point to a vitamin shortage, a medicine, or a body-wide condition. Most heal within two weeks. Anything that lasts longer should be examined.
Not sure what you're looking at?
Use our mouth spot checker. Tap where the spot is, pick what it looks like, and see the likely causes and how soon to have it examined. It takes about a minute and nothing you enter leaves your browser.
The two-week rule
Most mouth sores and spots are harmless and go away on their own within 7 to 14 days. Anything that hasn't healed or gone away in two weeks should be examined by a dentist or physician. That goes double for a white or red patch, a lump, or a sore that bleeds easily, feels hard, or isn't painful at all. Most of the time it turns out to be nothing serious. Checking is how you find out.
Don't wait two weeks for a hard or growing lump, a red or white patch with no clear cause, numbness, or a spot that bleeds easily or is changing fast. Have those examined promptly.
Find it by what you're seeing
Pick the description that fits best. Plenty of conditions show up in more than one group, so you'll see some names twice.
Sores and ulcers
- Round white or yellow sore with a red rim (canker sore)
- Mouth ulcers, blood blisters & chemo sores
- Blisters on the lip (cold sores)
- Many small sores plus a fever, often in kids
- Sores on one side only, with nerve pain
- Cracked, sore corners of the mouth
- A sore that won't heal
- Raw, sore mouth during chemo or radiation
White patches
Red patches or spots
Dark spots
Bumps and lumps on lips, cheeks or gums
Tongue changes
Roof of the mouth
Gums
- Red, puffy gums that bleed when you brush
- Receding gums, loose teeth or gum disease that won't clear up
- Very painful gums with gray, cratered tips
- Peeling or blistering gums
- Swollen gum with throbbing tooth pain
- Sore, swollen gum behind the last molar
- Gum problems that keep coming back with diabetes
- Swollen, bleeding gums with fatigue or bruising
Pain after dental work
Throat and tonsils
Burning or dryness with nothing to see
What causes oral lesions?
"Oral lesion" is the umbrella term dentists use for any sore, bump, patch or spot that doesn't belong. It isn't a diagnosis, and it doesn't mean cancer. Large surveys of biopsied mouth lesions find that most turn out to be harmless or reactive. The usual causes fall into a few groups:
- Injury and irritation. Biting your cheek, a pizza burn, a sharp tooth, a rubbing denture or harsh toothpaste. These cause most mouth ulcers, firm fibromas and lip mucoceles.
- Infections. The herpes virus behind cold sores, the yeast behind thrush, childhood viruses like hand, foot, and mouth disease, and bacteria in gum disease and a tooth abscess.
- Immune reactions. Canker sores, oral lichen planus and the less common autoimmune conditions covered below.
- Normal variation. Things like tori, Fordyce spots and fissured tongue that have probably been there for years.
- Nutrition and medicines. Low iron, B12 or folate can make the tongue sore and smooth (glossitis). Many medicines dry the mouth or change its color.
- Changes that need a biopsy. A white or red patch that won't wipe off, like leukoplakia or erythroplakia, can be precancerous. Rarely, a sore or lump is oral cancer. A biopsy is the only way to know.
Condition guides
Each guide has pictures or diagrams, look-alikes, home care, and when to get it checked.
Sores & infections
White, red & dark patches
Bumps & growths
Tongue
Gums & teeth
Wisdom teeth & extractions
Throat & salivary glands
Burning & dry mouth
Mouth signs of autoimmune and systemic disease
The mouth sometimes shows the first visible sign of a condition elsewhere in the body. Canker-like sores that keep coming back, a smooth sore tongue, peeling gums, unusual bleeding or a mouth that's always dry can all have a medical cause. When we see a pattern like that, we document it, treat the mouth, and send you to the right physician. Your doctor and lab tests make the diagnosis. We don't.
Start with the autoimmune and systemic conditions overview, or go straight to a condition:
If you already live with one of these conditions, tell us at every visit. It changes how we plan your care. Our page on dental care for medically complex patients explains how we work with your doctors.
Things that look strange but are usually normal
Lots of people find these for the first time while looking closely in a mirror and get worried. Most are normal anatomy or harmless variations:
- Bumps at the back of the tongue. A V-shaped row of large round bumps (circumvallate papillae) and ridged tissue along the back sides of the tongue (foliate papillae) are normal taste structures. See our tongue map.
- A white line along the inside of the cheek where your back teeth meet (linea alba). It comes from normal pressure and friction. If cheek biting leaves a firm bump, that's usually an irritation fibroma.
- Tiny yellow-white dots on the inside of the cheeks or lips (Fordyce spots). These are normal oil glands.
- A hard, bony bump in the middle of the roof of the mouth or on the tongue side of the lower jaw (tori). Harmless extra bone.
- A small bump just behind the upper front teeth. That's the incisive papilla, and everyone has one. It can get sore after a burn or a sharp chip.
- Grooves or cracks on top of the tongue (fissured tongue). Common and usually harmless. Brush the tongue to keep the grooves clean.
- Bumpy ridges inside the cheeks or scalloped tongue edges. Usually from clenching or pressing the tongue against the teeth.
If you're not sure whether something is normal, bring it up at your next visit. It takes us a few seconds to tell you.
How to take a useful photo of a spot in your mouth
If you want to send us a picture, or keep track of whether something is changing, a clear photo helps a lot:
- Use good light. Stand by a window during the day, or have someone shine a second phone's flashlight into your mouth.
- Turn off zoom and get close. Hold the phone 6 to 8 inches away and tap the spot on the screen to focus.
- Pull the lip or cheek out of the way with a clean finger, or hold your tongue with a piece of gauze.
- Take one close-up and one wider shot so we can see where in the mouth it is.
- Put something in the picture for size, like the tip of a pen or a ruler.
- Take another photo every few days from the same angle. Whether it's changing tells us a lot.
A photo is a helpful starting point. It doesn't replace an exam, especially for anything that hasn't healed in two weeks.
When to call a dentist about something in your mouth
Make an appointment if you notice:
- A sore, patch or lump that hasn't gone away in 2 weeks
- A white or red patch you can't wipe off
- A lump or thickened area in the cheek, tongue, gums or neck
- A sore that bleeds easily or feels hard around the edges
- Numbness in the tongue, lip or chin
- Sores that keep coming back, or a sore near a sharp tooth or appliance
- Gums that bleed every time you brush, or a sore tongue that won't settle
Get care the same day if:
- Swelling in your face, jaw or under your tongue is spreading, or you have fever with a mouth infection
- You have trouble swallowing or breathing (call 911 or go to the ER)
- Pain is so bad you can't drink fluids, or a child with mouth sores stops drinking
- Gums bleed for a long time on their own, especially with bruising, fever or fatigue
For urgent problems, see our emergency dental care page. A routine oral cancer screening is part of every comprehensive dental exam we do, and our oral medicine page explains how we look into sores and patches that don't have an obvious cause.
Common questions about mouth sores, bumps and patches
What causes white spots in the mouth?
The most common causes are oral thrush, which is a yeast infection that wipes off and leaves a red area underneath, and a white coating on the tongue from debris and bacteria. Fordyce spots are tiny yellow-white dots that are normal oil glands. Lacy white lines can be oral lichen planus, and a white patch that won't wipe off may be leukoplakia, which should be examined and often biopsied.
When should I worry about a mouth sore?
Have a mouth sore checked if it hasn't healed in two weeks, keeps coming back in the same spot, feels hard, bleeds easily, or doesn't hurt at all. Also get it looked at if it comes with a lump in the neck, numbness, or trouble swallowing. Most sores that meet these rules still turn out to be harmless, but an exam is how you find out.
What does an oral lesion mean?
An oral lesion is any area in the mouth that looks different from the healthy tissue around it, such as a sore, bump, patch or spot. It's a description, not a diagnosis, and it doesn't mean cancer. Most oral lesions are caused by injury, infection or normal variation and heal or stay harmless.
Why do I have bumps on my tongue?
Large round bumps in a V shape at the back of the tongue are normal taste buds called circumvallate papillae. Small, sore red or white bumps that appear suddenly near the tip are usually lie bumps, which fade in a few days. A bump that's firm, growing, or still there after two weeks should be examined.
What does mouth cancer look like?
Early mouth cancer can look like a sore that doesn't heal, a white or red patch that won't wipe off, or a firm lump or thickened area, often on the side of the tongue or the floor of the mouth. It's frequently painless at first. These signs are far more often caused by something harmless, and a biopsy is the only way to know. Our guide to the signs of oral cancer has pictures and a monthly self-check.
What is the bump on the roof of my mouth?
A hard, painless bump in the middle of the roof of the mouth is usually a torus palatinus, which is harmless extra bone. A sore bump just behind the front teeth is often an irritated incisive papilla, and a tender spot after hot food is usually a burn. A soft swelling near a tooth may be an abscess, and any bump that grows or is still there after two weeks should be checked.
What causes red spots in the mouth?
Red spots are most often from a burn, minor injury, a viral infection, or small blood spots on the soft palate from coughing or vomiting. Red, map-like patches on the tongue are usually geographic tongue, and redness under a denture is often yeast. A red, velvety patch that has no clear cause and lasts more than two weeks needs an exam, because it can be erythroplakia. Don't wait the full two weeks if it's growing, feels firm or comes with numbness.
Why are my gums sore?
Sore gums that bleed when you brush are most often gingivitis from plaque along the gumline. Other causes include brushing too hard, a canker sore on the gum, a gum flap over a wisdom tooth, or an abscess. Severe pain with gray, cratered gum tips needs prompt care, and gums that bleed on their own with bruising or fatigue should be checked by a doctor.
Are mouth sores contagious?
Some are and some aren't. Cold sores and hand, foot, and mouth disease are contagious, so avoid kissing and sharing drinks until they heal. Canker sores, geographic tongue, fibromas and most other bumps are not contagious.
How do I get rid of a mouth sore fast?
Most mouth sores heal on their own in 1 to 2 weeks. You can ease the pain with salt-water rinses, a protective paste or numbing gel used as the label directs, and by avoiding spicy, acidic and crunchy foods. Have your dentist smooth a sharp tooth edge or adjust an appliance that's rubbing the area. A dentist can prescribe a stronger gel or rinse when a sore is very painful or keeps coming back.
Can a vitamin deficiency cause mouth problems?
Yes. Low iron, vitamin B12 or folate can cause a red, smooth, sore tongue, cracked corners of the mouth, and frequent canker sores. A blood test from your physician can check for these, and it's better to test before starting supplements so the cause isn't missed.
Should I see a dentist or a doctor for a mouth sore?
A dentist is a good first stop for most sores, bumps and patches inside the mouth, because we look at mouth tissue every day and can examine, treat, biopsy or refer. See your physician first if the sore comes with a rash elsewhere, fever, joint pain, gut symptoms or unusual bruising. If you aren't sure, call us and we'll help you decide.
Something in your mouth you'd like checked?
Dr. Henley evaluates mouth sores, white and red patches, lumps, tongue changes and unexplained mouth pain for patients across Jacksonville. He also works closely with patients' physicians and cancer care teams when a problem calls for it.
Sources
- Weir JC, Davenport WD, Skinner RL. A diagnostic and epidemiologic survey of 15,783 oral lesions. J Am Dent Assoc. 1987;115(3):439–442.
- Lingen MW, et al. Evidence-based clinical practice guideline for the evaluation of potentially malignant disorders in the oral cavity: a report of the American Dental Association. J Am Dent Assoc. 2017;148(10):712–727.
- Warnakulasuriya S, et al. Oral potentially malignant disorders: a consensus report from an international seminar on nomenclature and classification, convened by the WHO Collaborating Centre for Oral Cancer. Oral Dis. 2021;27(8):1862–1880.
- Reamy BV, Derby R, Bunt CW. Common tongue conditions in primary care. Am Fam Physician. 2010;81(5):627–634.
- Plewa MC, Chatterjee K. Aphthous Stomatitis. StatPearls. National Library of Medicine; updated 2023.
- Vila T, Sultan AS, Montelongo-Jauregui D, Jabra-Rizk MA. Oral candidiasis: a disease of opportunity. J Fungi (Basel). 2020;6(1):15.
This guide is for general education and isn't a diagnosis. If you're worried about something in your mouth, see your dentist or physician. Photos marked Wikimedia Commons are used under their listed licenses and may have been cropped or resized.