Mouth ulcers are one of those small problems that can become surprisingly annoying. A tiny sore inside your cheek can suddenly make eating, drinking, talking and even brushing your teeth uncomfortable.
For some people, mouth ulcers appear once in a while and disappear within a week or two. For others, they keep coming back.
There is no single treatment that can prevent every mouth ulcer or make one disappear overnight. However, understanding your triggers can make them easier to manage. Your toothpaste is also worth looking at, particularly if you regularly experience irritation or recurrent mouth ulcers.
One ingredient that often comes up in this conversation is sodium lauryl sulphate (SLS). Some people with a sensitive mouth prefer an SLS-free toothpaste, so we will look at that early on before covering the other common causes, symptoms and treatment options.
Can Toothpaste Make Mouth Ulcers Worse?
Sometimes, it may.
Sodium lauryl sulphate, usually shortened to SLS, is a surfactant used in many toothpastes. It helps the toothpaste spread around your mouth and creates the foam most of us associate with brushing.
For most people, SLS does not cause a problem. But if you are prone to recurrent mouth ulcers, you may find that an SLS-containing toothpaste feels uncomfortable or irritating.
Some people who experience recurrent mouth ulcers find that SLS-containing toothpaste can feel irritating. If that sounds familiar, switching to an SLS-free toothpaste may be worth trying to see whether your mouth feels more comfortable.
If you are interested in looking more closely at what is inside your toothpaste, our guide to 6 toothpaste ingredients you may want to avoid and better alternatives to consider explains SLS and several other commonly discussed ingredients in more detail.
The important thing is not to stop brushing. Good oral hygiene still matters, even when your mouth is sore.
Edinco options without sodium lauryl sulphate
If you want to try a toothpaste without sodium lauryl sulphate, Edinco has a few different formulations to consider.
Rose Rio Aloe Vera + Propolis is SLS-free and fluoride-free. It uses decyl glucoside as its cleansing surfactant and also contains aloe vera leaf juice and propolis.
Rose Rio Matcha is also SLS-free and fluoride-free. It uses sodium lauroyl sarcosinate rather than sodium lauryl sulphate and contains xylitol, matcha extract and stevia.
MAXDENT Prebiotic is another SLS-free, fluoride-free option. Its formula uses sodium lauroyl sarcosinate and combines inulin and fructose with a blend of botanical extracts.
MAXDENT Sensitive is the option for people who want an SLS-free toothpaste with fluoride. It contains sodium fluoride and potassium nitrate and is formulated specifically with sensitive teeth in mind. Its ingredient list does not contain sodium lauryl sulphate, although it does contain sodium coco-sulfate
None of these toothpastes should be considered a treatment for mouth ulcers. They simply give you different options if you prefer to avoid SLS while choosing between a fluoride-free formula or a fluoride toothpaste for sensitive teeth.
None of these should be thought of as a treatment for mouth ulcers. They are simply options for people who prefer to avoid SLS as part of a gentler oral-care routine.
What Are Mouth Ulcers?
Mouth ulcers, also called canker sores or aphthous ulcers, are small sores that develop on the soft tissues inside the mouth.
You will usually find them:
- inside the cheeks
- inside the lips
- beneath the tongue
- on the floor of the mouth
- around the softer areas of the gums
A typical mouth ulcer has a white, yellowish or grey centre with a red border around it.
Even a very small ulcer can hurt, particularly when it comes into contact with spicy food, acidic drinks or your toothbrush.
Ordinary canker sores are not contagious. You cannot catch one by kissing someone, sharing a drink or using the same cutlery.
Cold sores are different and should not be confused with mouth ulcers.
What Do Mouth Ulcers Look and Feel Like?
You may notice an ulcer before you can actually see it.
Some people experience a slight burning, tingling or prickling feeling in one area of the mouth. A small red area can then develop into a shallow sore.
Common mouth ulcer symptoms include:
- a round or oval sore inside the mouth
- a white, yellowish or grey centre
- redness around the edge
- pain or burning while eating
- discomfort while brushing
- sensitivity to spicy, salty or acidic foods
- discomfort when talking or swallowing
You might have one ulcer or several at the same time.
Most minor mouth ulcers heal by themselves, but ulcers that are unusually large, persistent or repeatedly returning deserve more attention.
Different Types of Mouth Ulcers
Not every mouth ulcer behaves in the same way.
Minor mouth ulcers
Minor aphthous ulcers are the most common type.
They are usually small, round or oval and less than 10 mm across. They may hurt, but they are generally shallow and usually heal within one to two weeks.
Minor ulcers normally heal without leaving a scar.
Major mouth ulcers
Major ulcers are larger and deeper.
They can be 10 mm or more across and may be considerably more painful than minor ulcers.
Because they extend deeper into the tissue, they can take several weeks to heal and may sometimes leave scarring.
If you develop a large ulcer that is particularly painful or slow to heal, speak to a dentist or GP.
Herpetiform ulcers
Herpetiform ulcers are clusters of very small aphthous ulcers.
Despite the name, they are not caused by the herpes virus.
The small ulcers may join together and form a larger sore area. They can take several weeks to settle.
What about cold sores?
Cold sores are different from aphthous mouth ulcers.
They are caused by the herpes simplex virus and commonly appear around the lips as fluid-filled blisters.
Unlike ordinary mouth ulcers, cold sores are contagious.
What Causes Mouth Ulcers?
There is rarely one simple explanation.
The exact cause of mouth ulcers can differ from one person to another, and sometimes no obvious trigger can be identified at all.
A few factors appear again and again.
1. Minor injuries
Sometimes the explanation is very simple.
You may accidentally bite the inside of your cheek, brush too hard or irritate the tissue with a dental appliance.
Because the lining inside your mouth is delicate, a relatively small injury can sometimes lead to an ulcer.
2. Stress
Many people notice that their ulcers appear during particularly stressful periods.
Stress does not explain every case, and it is not always possible to prove that it caused a particular ulcer. But it may be a trigger in people who are already prone to them.
3. Nutritional deficiencies
Low levels of iron, vitamin B12 or folate have been associated with recurrent mouth ulcers.
If you develop them frequently, particularly alongside other symptoms, your GP may recommend blood tests to look for a deficiency.
This is better than simply taking supplements without knowing whether you actually need them.
4. Food irritation
Certain foods can make an existing ulcer feel much worse.
Common examples include:
- citrus fruits
- tomatoes
- spicy food
- very salty food
- acidic drinks
That does not necessarily mean these foods caused the ulcer in the first place.
Instead of cutting out lots of foods unnecessarily, pay attention to your own patterns and see whether particular foods consistently cause discomfort.
5. Toothpaste ingredients
As mentioned earlier, SLS may be worth considering if you repeatedly experience mouth ulcers or irritation.
That does not mean every person with mouth ulcers needs to avoid SLS. But switching to an SLS-free toothpaste for a period of time can help you work out whether your mouth feels more comfortable without it.
6. Family history
Recurring mouth ulcers sometimes run in families.
If close relatives also experience them frequently, genetics may be one part of the picture.
Can Recurrent Mouth Ulcers Be Linked to Other Health Conditions?
Sometimes.
Most ordinary mouth ulcers are not a sign of a serious disease, but recurrent or unusual ulcers can occasionally occur alongside other medical conditions.
These may include:
Coeliac disease
Coeliac disease affects the body's response to gluten and can also lead to nutritional deficiencies. Mouth ulcers may occur in some people with the condition.
Inflammatory bowel disease
Conditions such as Crohn's disease and ulcerative colitis can sometimes be accompanied by oral ulcers.
Behçet's disease
This is a rare inflammatory condition that can cause recurrent mouth ulcers alongside other symptoms, including genital ulcers and inflammation elsewhere in the body.
Conditions affecting the immune system
Some immune-related illnesses can also be associated with oral ulceration.
This does not mean that having a mouth ulcer suggests you have one of these conditions.
If your ulcers are frequent, severe or accompanied by symptoms such as persistent digestive problems, fever, unexplained weight loss or ulcers elsewhere on the body, speak to a healthcare professional rather than trying to diagnose the cause yourself.
What Is the Best Toothpaste for Mouth Ulcers?
If you regularly get mouth ulcers, the best toothpaste is usually one that cleans effectively without making your mouth feel more irritated.
For many people, that means starting with an SLS-free toothpaste, especially if their current toothpaste feels harsh, foamy or uncomfortable when an ulcer is present.
It can also help to choose a formula with a milder flavour and avoid anything that causes a noticeable burning or stinging sensation.
If you want fluoride protection as well, an SLS-free fluoride toothpaste can be a good choice. If you prefer a fluoride-free formula, there are also SLS-free options available.
The most important thing is how your mouth responds. If switching toothpaste makes brushing more comfortable and you notice fewer episodes of irritation, that may be a better fit for you.
For persistent or frequently recurring mouth ulcers, toothpaste should only be considered one part of the picture, and it is worth speaking to a dentist or GP to rule out other possible causes.
For most people with a sensitive mouth, the practical questions are much simpler:
Does it clean my teeth properly?
Does it irritate my mouth?
Can I comfortably use it twice a day?
Those questions are often more useful than whether the front of the tube says “natural”.
Does Natural Toothpaste Help Mouth Ulcers?
Natural toothpaste can be a good option for people with a sensitive mouth, especially if they prefer formulas built around plant-derived ingredients and want to avoid ingredients that they personally find irritating.
Across the Edinco range, several toothpastes use naturally derived or botanical ingredients in different ways.
Rose Rio Aloe Vera + Propolis contains aloe vera leaf juice and propolis extract, while Rose Rio Matcha includes matcha green tea extract, xylitol and stevia.
Rose Rio Rose Water contains Rosa damascena flower water, and Rose Rio Lavender Water uses Lavandula angustifolia flower water.
Rose Rio Spirulina includes spirulina extract, while MAXDENT Prebiotic combines inulin and fructose with a blend of botanical extracts such as chicory root, liquorice root, ginger, witch hazel and perilla, together with peppermint and tea tree oils.
MAXDENT Sensitive also includes plant-derived ingredients such as chamomile extract and clove oil, while MAXDENT Charcoal Whitening contains charcoal powder, spearmint oil and wintergreen oil.
If you are choosing a natural toothpaste for mouth ulcers or a sensitive mouth, these ingredients can be part of the reason one formula appeals to you more than another. But comfort still comes first. If SLS seems to make your mouth feel irritated, choosing one of Edinco’s SLS-free options may be more relevant than simply choosing a toothpaste because it contains natural ingredients.
If ingredient labels feel confusing, our toothpaste ingredients explained guide breaks down what common toothpaste ingredients actually do and why they are included in a formula.
Mouth Ulcer Treatment: What Can You Do at Home?
Most minor mouth ulcers get better without specific treatment.
While you wait for the ulcer to heal, the main aim is to reduce irritation and keep your mouth clean.
Brush gently
Do not stop brushing simply because you have an ulcer.
Use a soft-bristled toothbrush and take a little more care around the painful area.
Aggressive brushing can make an already sore mouth even more uncomfortable.
Avoid foods that sting
If citrus fruits, spicy food or acidic drinks make the ulcer burn, avoid them temporarily while it heals.
You do not need to permanently remove these foods from your diet unless you have another reason to do so.
Keep your mouth clean
Plaque and food debris do not help an already uncomfortable mouth.
Continue brushing gently and clean between your teeth using floss or interdental brushes if you can do so without injuring the area.
Consider an SLS-free toothpaste
If you regularly develop ulcers and currently use an SLS-containing toothpaste, trying an alternative may be worthwhile.
It will not prevent every ulcer, but it may help if SLS happens to be one of your personal triggers.
Speak to a pharmacist, dentist or GP if needed
If the pain is significant, a healthcare professional can advise you about appropriate mouth ulcer treatment, such as protective gels or suitable pain-relieving products.
More persistent or severe cases may need prescription treatment.
How Can You Help Prevent Mouth Ulcers?
Unfortunately, there is no guaranteed way to prevent every mouth ulcer.
But there are a few practical things you can do.
Notice your triggers
If your ulcers seem to appear after particular foods, stressful periods or changes in oral-care products, make a note of it.
Patterns are easier to spot when you actually pay attention to them.
Eat a balanced diet
A varied diet helps provide nutrients such as iron, vitamin B12 and folate.
If you think you may be deficient, seek medical advice rather than guessing.
Avoid repeatedly injuring the same area
A sharp tooth, broken filling, poorly fitting dental appliance or repeated cheek biting can keep irritating the same tissue.
If something in your mouth is repeatedly rubbing or catching, ask your dentist to check it.
Use a soft toothbrush
A soft-bristled brush can clean effectively without unnecessarily traumatising the delicate lining of the mouth.
Consider your toothpaste
If you have recurrent mouth ulcers, switching from an SLS-containing toothpaste to an SLS-free alternative may be worth a trial.
Give yourself enough time to see whether you notice a meaningful difference.
Manage stress where possible
Exercise, sleep and making time to unwind will not guarantee that ulcers disappear, but if stress seems to trigger yours, managing it may help reduce one contributing factor.
When Should You See a Dentist or GP About a Mouth Ulcer?
Most minor mouth ulcers improve within one to two weeks.
But not every ulcer should simply be ignored.
Arrange an assessment if an ulcer:
-
lasts longer than three weeks
- is unusually large
- becomes increasingly painful
- keeps coming back very frequently
- makes eating or drinking difficult
- looks noticeably different from your usual ulcers
- occurs alongside other unexplained symptoms
A dentist or GP can examine the area, look for possible causes and decide whether further investigation is needed.
Persistent mouth ulcers should always be checked rather than repeatedly self-treated.
Final Thoughts
Mouth ulcers are common, painful and usually short-lived. For many people, the hardest part is simply working out why they keep coming back.
Sometimes there is an obvious trigger, such as biting your cheek. In other cases, factors such as stress, nutritional deficiencies or an underlying condition may contribute.
Your toothpaste may also be worth considering.
If you regularly experience recurrent mouth ulcers and use a toothpaste containing sodium lauryl sulphate, trying an SLS-free toothpaste is a reasonable step. Edinco options such as Rose Rio Aloe Vera + Propolis, Rose Rio Matcha and MAXDENT Prebiotic provide different formulations without sodium lauryl sulphate, allowing you to choose according to your wider oral-care preferences.
The aim is much simpler: keep your teeth clean, avoid unnecessary irritation and pay attention to what seems to work best for your mouth.
And if an ulcer does not heal within three weeks or keeps returning without an obvious reason, have it checked by a dentist or GP.
Frequently Asked Questions
What causes mouth ulcers?
Common triggers include stress, minor injuries, certain foods, nutritional deficiencies and irritation from oral-care products.
Can toothpaste cause mouth ulcers?
Some toothpaste ingredients can irritate the mouth in people who are prone to ulcers.
Is SLS-free toothpaste better for mouth ulcers?
It may help if SLS irritates your mouth. Some people find SLS-free toothpaste more comfortable to use.
What is the best toothpaste for mouth ulcers?
Choose a toothpaste that cleans well without causing extra irritation. An SLS-free formula can be a good option.
Can natural toothpaste help mouth ulcers?
Natural toothpaste may feel gentler for some people, but it should not be considered a treatment for mouth ulcers.
Which Edinco toothpastes are SLS-free?
Rose Rio Aloe Vera + Propolis, Rose Rio Matcha, MAXDENT Prebiotic and MAXDENT Sensitive.
How long do mouth ulcers last?
Most minor mouth ulcers heal within one to two weeks.
When should I see a dentist or GP?
Get an ulcer checked if it lasts more than three weeks, keeps returning or becomes unusually painful.
Are mouth ulcers contagious?
No. Ordinary canker sores are not contagious.
How can I make a mouth ulcer less painful?
Brush gently, avoid foods that sting, keep your mouth clean and consider switching to an SLS-free toothpaste if your current one feels irritating.
