Canker Sores | Everything You Need To Know

canker sore on lip

Some of the most common sores to get in your mouth are aphthous ulcers or “canker sores.” Most people just call them “ulcers” for short. And even though they’re usually pretty small, they can be super painful.

Since aphthous ulcers impact the soft gingiva and mucous membranes inside of our mouths (all of that pink skin, aka “mucosa”) they’re really easy to notice. They can even be so painful that it’s hard to eat anything other than something soft like a milkshake.

Canker Sore Symptoms

The biggest symptom you’re going to notice with a canker sore is the pain. And by pain, we mean some pretty moderate discomfort. It might start out as a small amount of irritation or tingling, but a fully developed ulcer will usually feel like it’s burning. It will usually hurt the worst when you touch it or move your mouth around so that the surface of the ulcer is rubbed. And of course, eating or drinking can make the ulcer hurt too.

Visibly, the symptoms of ulcers are pretty clear cut. Once you pull your lip back to see what’s going on inside of your mouth, you’ll likely notice a small white circle or oval with a well-defined margin around it. Typically, you’re going to see a bright pink or red edge around the white area. Sometimes aphthous ulcers are even yellow, pink, or a little brown, depending on which stage of the ulcer you’re in and if it’s infected.

A canker sore will usually be by itself, without any other sores around it. So, if you have a collection of sores or other symptoms, such as blisters or lesions on your lips, you might have another type of condition called a cold sore (which is caused by a virus.)

Types Of Canker Sores 

1) Minor Canker Sores

The most common type of aphthous ulcer is a minor canker sore. It’s small – usually just 2-3mm wide – and just inside of your cheek, lip, or on the floor of your mouth. More often than not, it will pop up quickly and then heal over the next couple of weeks.

Minor canker sores affect people of all ages, from infants on up to adults. If you notice that your toddler is cranky, doesn’t want her teeth brushed, or your child says it hurts to eat, take a quick peek inside of their mouth to check for any signs of an aphthous ulcer. However, the biggest age group to suffer from minor aphthous stomatitis (another fancy term we use to describe ulcers) is adolescents.[1] It might be because of changing hormones and that it’s a time in oral development where most teens get braces, both of which are risk factors.

It doesn’t necessarily mean that there’s anything wrong if you get an ulcer, but if they keep recurring it could be a warning sign of something going on with the rest of your body. In most cases, these small ulcers are bothersome, but not really big problems to worry about. 

2) Major Canker Sores

If you’re unlucky enough to be one of the people who gets a major canker sore – which, might I add, is way less common than minor ulcers – you might need a little help from your dentist to manage the pain while it starts to heal.

Major canker sores are a lot larger and deeper, meaning they can almost look like a shallow area scooped out of your mucosal tissues (remember, that’s the soft pink skin inside of your mouth.) These are the ulcers that are probably going to be bigger than a centimeter across.[2]

A major sore can take longer than a couple of weeks to heal, simply because of how large it is. And when they finally do heal, there’s a really good chance that they’ll leave a scar behind.

3) Herpetiform Canker Sores

Fewer than 5% of ulcers are what we call “herpetiform”.[3] That is, they come in a cluster of multiple small aphthous ulcers all crowded next to each other. With herpetiform ulcers, each one is usually less than about 1mm across (the size of a pinhead.) When you get them, you might have anywhere from 10 to 100 of them!

The difference between regular ulcers and herpetiform versions is that the latter is usually associated with a viral infection. More specifically, the herpes simplex virus.

Now don’t freak out. This doesn’t mean you have that kind of herpes. It just means that one of the many different herpes strains somehow got passed around and ultimately made its way into your body. And before you start jumping to any conclusions, the herpes virus is also associated with Chicken Pox and shingles. Technically if you kiss or drink after somebody with a cold sore in their mouth, you can contract the virus.

Canker Sores Vs. Cold Sores

Canker sores and aphthous ulcers are NOT the same thing as cold sores or fever blisters. The latter are due to viruses inside of your body that flare up for one reason or another. But ulcers are not caused by viral infections. Rather, they’re typical because of some type of physical force causing irritation to that specific area of your mouth.

Think about it like a blister on your foot, if you’re wearing a new pair of shoes or your sock doesn’t cover a specific area. At the end of the day, you’ll probably have a raw, sore area that is going to take several days to get back to normal before it doesn’t hurt anymore. But it’s not caused by a virus. That’s basically the difference when you’re comparing regular ulcers with cold sores. 

Cause Of Canker Sores

1) Stress 

What can’t be blamed on stress? From losing weight to high blood pressure, stress strains your body from head to toe. It can also make your ulcer flare-ups more frequent.

2) Braces 

Orthodontic patients may notice that they get more ulcers right after their braces are put on or following adjustment appointments. The ulcers are caused by repetitive irritation in areas where brackets or ends of wires press into their cheeks.

3) Trauma 

A simple slip of your toothbrush or biting onto a large piece of a tortilla chip may be all that it takes to cause a surface injury to your oral mucosa. After a short period of time, it’s not uncommon for an ulcer to flare up.

4) Acidic Foods And Drinks 

Your morning glass of orange juice, having tomato soup at lunch, or cooling off on a hot afternoon with a tall glass of lemonade are all common examples of items with acidic pH levels that can irritate your mouth.

5) Allergies 

Anything from a food allergy to active ingredients in your toothpaste can trigger irritation inside of your mouth. Pay attention to what you’re putting into your body to see if you can find the link.

6) Deficiencies  

Did you know that not having enough iron or B12 can affect your immune system and make you more prone to getting canker sores? Other vitamins and minerals you’ll want to stay on top of include zinc and folic acid.

7) Hormonal Changes  

Some females experience ulcers more often around their period. So, pay attention to when yours are flaring up to see if it has anything to do with your hormonal cycles. (Yep, one more thing to blame on your period, ladies!)

8) Celiac Disease Or Chron’s Disease 

Both of these disorders affect your gastrointestinal tract, including the mucous membranes of your mouth. If you think about how harsh they are on the insides of our intestines, it’s easy to see why your mouth could suffer from flare-ups too.

9) Medication 

Yep. Certain prescription and over-the-counter drugs are linked with a higher chance of oral ulcers.[4] Everything from aspirin and oral nicotine to Antibiotics and blood pressure meds can be to blame. If you’re taking what’s called an “NSAID” (non-steroidal anti-inflammatory drug) like ibuprofen or naproxen to relieve the pain of your ulcer but you find that it’s actually getting worse, it could be the medication itself that’s contributing to your canker sore.

When To See A Doctor

Although most canker sores will resolve on their own within a couple of weeks, there are situations where you may need to seek out the help of your dentist. For instance, if your ulcer is major and so painful that you’re unable to eat, your dentist can prescribe a special mouth rinse with lidocaine (a numbing medication) to help desensitize the sore area and offer pain relief.

Additionally, you need to see a dentist if symptoms don’t improve within 10-14 days. Since aphthous ulcers can potentially mimic the symptoms of oral cancer, you need to make sure there’s not something more serious going on. Delayed healing is typically a red flag.

Some dentists’ offices are even equipped with fancy, super-safe dental laser technology where they can literally “zap” – ok it’s not really called that, but you get the idea – your ulcer so that it feels better the very same day.

If for any reason you start to develop a rash, fever, nausea, or other symptoms, let your doctor or dentist know right away. Additionally, if the sore starts to spread or get worse after a few days, call their office. You need to make sure it doesn’t evolve into something like a staph infection.

How To Treat Canker Sores

1) Wait It Out

If it doesn’t hurt all that much, just let it heal on its own. Take care not to irritate the area with acidic foods or drinks, salt, or with your toothbrush. If your ulcer is small, you can usually make it a couple of weeks without any further treatment.

2) Apply A Topical Analgesic

Brands like Orajel help to temporarily numb the mucous membranes where your ulcer is so that you can get through a meal without it bothering you too much. However, this isn’t something you want to apply more than a couple of times per day for more than a few days in a row. It’s not made for that.

3) Ask Your Dentist About “Miracle Mouthwash”

This special rinse has numbing medications combined with liquid Maalox (yep, the stuff you take for heartburn) and a third ingredient, diphenhydramine, which is an antihistamine. When you combine them all together, you can gargle, rinse, or dab the solution onto major ulcers for pain relief as it heals.

And finally, you have the option to ask about laser ulcer treatments. Soft tissue laser therapy takes just a matter of seconds and can safely cauterize the outer layer of your ulcered area, to help speed up the healing process. 

How To Prevent Canker Sores

If you’re someone who gets canker sores on a regular basis, the best way to prevent them is to try to figure out what your triggers are. Try to keep a diary of every time you get an ulcer and list what products or foods are going inside of your mouth in the few days prior – including drinks, foods, medications you’re taking, and even the brand of toothpaste you’re on. Some people are allergic to toothpastes with “sodium lauryl sulfate” (SLS) in them; so, if you use one and get ulcers, try switching to a different formula to see if it helps.

For people who wear braces, pay attention to areas inside of your mouth that might be rubbing against a bracket or wire. Even though your mouth will eventually get used to your orthodontic appliances, any rough edges can be covered with wax to prevent them from rubbing your mouth and causing an ulcer.  

Aphthous Ulcer Recap

Most canker sores are minor and heal on their own within a couple of weeks. Major canker sores can take longer to recover from, and you might need to invest the help of your dentist simply because of how painful they are.

Herpetiform ulcers are not the same thing as canker sores and are caused by viruses, whereas aphthous ulcers are typical because of irritation or certain foods. Always see your dentist if the ulcer doesn’t heal within two weeks.