How To Tell the Difference Between a Cold Sore and Canker Sore

What causes mouth sores?

It never fails. An important day arrives, and you wake up with a sore in your mouth. Perhaps you bit your lip or cheek the night before. Maybe it was an allergic reaction. Or perhaps you are just stressed out and your body is reacting to that stress. But what type of sore do you actually have? Is it a cold sore, a canker sore, or something else? Read on to learn the differences between mouth sores.

Mouth sores are a common complaint among adults in their 20s and 30s, but it isn’t always clear as to why those sores develop. However, understanding the cause of your mouth sore is the first step in determining how to treat it so that it goes away quickly. After all, these painful oral lesions can not only be embarrassing but also interfere with everyday activities like speaking and chewing.

There are many causes of mouth ulcers, ranging from common injuries to serious health conditions. The most common mouth sore causes include:

• Biting your lip, tongue, or cheek
• Irritation due to orthodontic devices
• Using a hard-bristled toothbrush or brushing too hard
• Smoking, vaping, or using chewing tobacco
• Hormonal changes
• Stress
• Burns from hot food or drinks
• Herpes simplex virus

Less frequently, however, mouth sores can be caused by certain health conditions. Most notably, you may develop a mouth sore if you have one of the following:

• Anemia
• Celiac disease
• Crohn’s disease
• Folate deficiency
• HIV
• Human papillomavirus (HPV)
• Hand, foot, and mouth disease
• Irritable bowel syndrome (IBS)
• Lupus
• Mononucleosis
• Pemphigus vulgaris 

Differences Between Cold Sores and Canker Sores

Now that you know the various reasons mouth sores can develop, the next step is to figure out if it is a cold sore or canker sore. The main difference is quite simple: a cold sore is contagious, whereas a canker sore is not.

Cold Sores

Cold sores, commonly referred to as fever blisters, are groups of fluid-filled blisters that erupt around the lips, under the nose, or around the chin. These contagious sores result from the herpes simplex virus. Unfortunately, once you have become infected by the virus, it remains in your bloodstream. Doctors often prescribe antiviral pills or creams to help the sores heal faster. Cold sores spread through close contact such as kissing. Typical symptoms include tingling or itching, blisters, oozing, and crusting.

It is best to see your doctor if any of the following applies to you:

• You have a compromised immune system.
• The cold sores are still present after two weeks.
• Your symptoms are severe and causing moderate to severe discomfort.
• Your cold sores recur frequently.
• You have irritated eyes in combination with your cold sores.

Canker Sores

Canker sores are small, red-bordered, grayish ulcers that form inside the mouth. These noncontagious sores are usually caused by fatigue, stress, or allergies. They generally heal on their own within around two weeks.

Symptoms of a canker sore are a bit less obvious than those of a cold sore. Be on the lookout for a painful sore inside your mouth, a tingling or burning sensation, or visible red-bordered, grayish lesions. Pain from a canker sore generally fades after a few days, usually without treatment. You can purchase over-the-counter products, such as Kank-A, Zilactin, or Orajel, to help relieve discomfort. However, if you are experiencing a fever, swollen lymph nodes, or fatigue in conjunction with your canker sore, it is best to see a medical professional.

Can I see the dentist if I have a cold sore or canker sore?

Since canker sores are not contagious, it is not necessary to cancel or reschedule a dentist appointment that might occur concurrently. However, the decision to keep or reschedule an appointment may vary from patient to patient and is a personal decision based on comfort. If your canker sore is causing oral discomfort, it may be best to reschedule your appointment for a week or two until the sore is healed and you are feeling better.

When it comes to a cold sore, however, it is best to contact your dentist before your appointment. Active cold sores can be painful and cause bleeding or irritation, which means that your dentist may advise you to reschedule your appointment. 

When in doubt, give your dentist a call. If you are looking for a dentist in Wasilla, Alaska, and have questions about mouth sores or whether you should reschedule your appointment, give Valley Dental Clinic a call. We’ll be happy to provide guidance on what to do. Most importantly, remember that mouth sores are common and are nothing to be ashamed of. In fact, 50% to 80% of U.S. adults have oral herpes. But taking steps to ease your pain can make all the difference in getting back to your life quickly.