Canker sores appear as a white oval on the cheeks lips palate and tongue that last for one week

Canker Sores = Aphthous Ulcers

A lot of patients confuse the terminology for Canker Sores and Cold Sores.  They may use many other words such as:  Fever Blisters, Sun Blisters, Herpes Labialis, Herpes Type I, and Aphthous Ulcers without understanding the difference.  This section discusses Canker Sores (Aphthous Ulcers).  Cold Sores (Herpes, Fever or Sun Blisters) are discussed in the next section. 

Canker sores are Aphthous Ulcers.  Canker sores appear as a white oval on the cheeks, lips, palate and tongue that typically lasts for one week.  They usually occur as a solitary, larger lesion that appears on the red oral tissues like the inside of the cheek.  They can also be quite painful.  Unlike Herpes, canker sores are not considered a sexually transmitted disease and are not contagious.  People may get them with irregular frequency and they can be associated with stress or during immune supression like when getting the flu.  Canker sores usually last for seven to ten days. 

Treatment:  In our office we use a medication that can greatly reduce the pain severity and duration of an outbreak.  The medicine causes a chemical cautery (burn) on the canker sore.  The exposed nerve endings of the canker sore are covered in a callus that forms in response to the burn. The callus will last for one week but during that time nearly all of the pain associated with the canker sore will be gone. This medicine may also help those suffering pain associated with Oral Mucositis.  The treatment itself is relatively painless and takes only a few minutes.

To see comparative photographs click on “Dental Photos” at the top of this page and then click on “Aphthous Ulcer” in the left margin. Hundreds of photographs are in this section.

This material is presented for patient information.  Patients need to be diagnosed and treated by their dentist or doctor.

Canker sores (also known as Recurrent Aphthous Stomatitis, RAS or Recurrent Aphthous Ulcers, RAU) are oral lesions that occur for an unknown reason in about 10% of the population.  They frequently recur several times a year.  Immunosuppressed people are more likely to get major canker sores.  Major canker sores can reach up to one half inch and last for more than one month.  All canker sores can be extremely painful.  The pain from canker sores can prevent people from eating and/or drinking; this can lead to malnutrition and dehydration. 

Biting the inner lining of the mouth (cheek biting, pizza burn), diet, stress, or an allergic reaction to a food, toothpaste or mouthwash can cause a canker sore.  Vitamin B12 & folate deficiency, gluten sensitivity, allergy to sodium lauryl sulfate in toothpaste and smoking cessation can also cause canker sores. Women develop canker sores more than men.  People who have Ulcerative Colitis, Crohn’s Disease and Celiac Disease will frequently have more canker sores.  It also appears more frequently in people who have Neutropenia, Reactive Arthritis, HIV/AIDS and those undergoing Cancer Chemotherapy who develop Oral Mucositis.  There is a genetic component to canker sores.

Treatment for canker sores include: analgesics, anesthetics, antiseptics, anti-inflammatory agents, steroids, fumaric acid esters, sucralfate, tetracycline suspension and silver nitrate.  Two common anesthetic gels applied to aphthous ulcers are Benzocaine and Lidocaine.  Another approach would be to use topical Benzydamine Hydrochloride (Amlexanox), an anti-inflammatory, anti-allergic medication.

Barriers, such as topical Hyaluronic Acid or Cyanoacrylate adhesives, are also used to relieve the pain associated with canker sores.  Topical Hyaluronic Acid acts as a protective barrier and serves as an anti-oxidant.

Antimicrobials may reduce the pain of a canker sore and aid healing.  Some antimicrobials used are Chlorhexidine, Triclosan, Tetracycline, and Penicillin G.  Chlorhexidine comes in a 0.2% mouth rinse or 1% gel.  Triclosan is an anti-inflammatory and antimicrobial agent that is used to reduce the number of canker sores, relieve pain, and shorten duration.  There is some safety concern, however, about the use of Triclosan.  Penicillin G can be used to reduce the pain, duration and size of the ulcer.  Tetracycline has an anti-inflammatory effect.

Steroids and Immunomodulation can also be used in the canker sore healing process as well.  Steroids come in mouth rinses (Betamethasone Valearate), ointment, and creams (Triamcinolone Acetonide).  Immunomodulation treats canker sores by affecting the immune system.  A few immunomodulators are Thalidomide, Colchicine, Pentoxifylline, Levamisole, Dapsone, and Cimetidine.  The immunostimulant, Thalidomide, is especially useful in HIV positive patients with RAS.  Some adverse drug reactions may occur.  Levamisole will reduce the pain and frequency of ulcers and also promotes healing.

Other medications used to treat canker sores are:  Adalimumab, Alefacept, Cyclophosphamide, Cyclosporine, Dapsone, Efalizumab, Etanercept, Infliximab, Interferon, Methotrexate, and Penoxifylline.  Herbal remedies include:  Sage, Echinacea, Licorice Root, Chamomile and Myrrh.  Magic Mouthwash provides a limited benefit.  Milk of Magnesia, Hydrogen Peroxide, salt water rinse and liquid antihistamines can be used as mouth rinses.  Silver Nitrate Sticks cause a chemical burn when applied to the canker sore. 

Physical Treatment may include: laser ablation, chemical cautery, surgical removal, and low dense ultrasound.  Laser therapy reduces canker sore pain and may reduce the frequency of recurrence.  Freezing the canker sore (Cryotherapy) does not work.

To see comparative photographs click on “Dental Photos” at the top of this page and then click on “Aphthous Ulcer” in the left margin. Hundreds of photographs are in this section.