Mouth Spots and Sores

This section provides information mouth sores including their causes and treatment.

You should visit your dentist immediately if you notice mouth sores. Your dentist can then make a proper diagnosis and recommend you the most suitable treatment plan. 

Sores can occur anywhere on mouth soft tissues including the lips, tongue, gums, cheeks or roof of the mouth (palate). Mouth sores are usually painful, irritating and mouth sores can be painful, annoying and unpleasant to look at. Cold sores usually develop outside the mouth; on the lips, nose or chin.

Some of the causes of mouth sores include oral cancer, bacteria, viruses and fungi. Other causes of mouth sores include: 

  • Denture irritations; loose dentures can cause sores and soreness in the mouth.
  • Protruding orthodontic wire or any sharp edge due to a broken filing or natural tooth.
  • Sensitivity to irritants contained in certain dental products.
  • Reaction to certain medication or therapy for example side effects of cancer treatment.
  • Certain diseases (systemic, skin or oral).

Common mouth sores include cold sores, canker sores, leukoplakia (thickened white or grey patches) and candidiasis (a yeast infection also known as thrush). Some mouth spots and sores are painless and harmless but some may be severe and require your attention. Usually there is no pain during the early stages of oral cancer even though it can get lethal. It is for this reason that you are advised to visit your dentist regularly. Seek help from your dentist in case you have sores or spots that take longer than 2 weeks to heal.



Canker Sores

Canker sores also known as aphthous ulcers develop on soft tissues in the mouth. Canker sores are normally small, painful sores with red borders and white, grey or yellow centers. Seldom do you find large canker sores with raised borders. You may have one or more canker sores at a particular time and usually they reappear after varying durations of time. Canker sores normally start as red spots or bumps that are tingly and normally heal by themselves in 7-10 days.While what actually causes canker sores remains unknown, genes have been found to have a significant influence the development of these sores.

White blood cells also known as lymphocytes can affect the mouth lining triggering the occurrence of canker sores. Some other factors that can trigger the occurrence of these sores include fatigue, stress and particular types of foods. Additionally, injuries to the tongue or soft tissues inside the mouth resulting biting yourself or due to sharp objects or foods can cause canker sores.

Canker sores cannot be transmitted from one person to another and are also not pre-cancerous. Treatment for canker sores only reduces discomfort and irritation but does not permanently cure the sores. Topical over-the-counter medicines including anesthetics and antimicrobial mouth raises can help temporarily reduce discomfort. Stay away from hot, acidic or spicy foods and drinks that may aggravate the sore. Canker sores are treated using corticosteroids medicines such as prednisone which control the reaction of white cells in the body. Some of these medications can be topical (applied directly on the affected area) or systemic (in form or capsules or tablets).

Cold Sores

Cold sores also known as fever blisters occur in groups; are painful and filled with fluid. Cold sores normally appear on and around the lip area. These groups of tiny sore can also erupt on gum tissue that is near teeth or also on the hard palate (upper part of the mouth that is bony).

The Herpes Type 1 and Type 2 virus can cause cold sores which are transmissible. The first herpes infection known as primary herpes usually occurs during childhood and its symptoms are similar to the symptoms of flu or cold. The herpes infection may lead to the occurrence of painful sores all over the mouth. Sometimes patients may fall sick for about seven days.Nevertheless majority of people with herpes never get sick. Once you get infected with the herpes virus it remains in your body but in an inactive state. However, for a number of people the HPV gets activated from time to time causing cold sores to erupt on and around the lips. Cold sores can be aggravated by sun, wind, stress and fever.  

Cold sores normally take up to 7 days to heal. When a sore breaks, it oozes then forms a scab that is unpleasant to look at. Topical over-the-counter medicines including anesthetic gels and protecting gels, anti-inflammatory and antiviral agents can temporarily ease pain but do not speed up healing. Just like other viral infections, cold sores cannot be permanently cured. Your dentist may recommend topical (applied directly on the affected area) systemic (in form or capsules or tablets) antiviral medication. These drugs are only effective immediately after blisters have formed and are not to be used by healthy people.


Leukoplakia is a term used to refer to gray or white patches that form on tissues inside the mouth. Leukoplakia occurs due excessive growth of cells lining the mouth. Leukolakia is usually caused by tobacco use (chewing and/or smoking); particular types of food, cheek biting, uneven tooth restorations or cracked teeth.The cause of this condition is unknown in some people. Leukoplakia patches form gradually and with time may become rough. These patches are generally painless and non-irritating.

Generally Leukoplakia is harmless; however it is linked to oral cancer. Visit your dentist to establish whether a patch or spot is cancerous or not. A biopsy will conducted to rule out the risk of cancer.


Erythroplakia is a term used to refer to red patches that can occur inside the mouth. Erythroplakia patches commonly appear on gum tissues behind back teeth or on the floor of the mouth. It is not known exactly what triggers Erythroplakia but it is commonly linked to tobacco use (chewing and/or smoking) and alcohol consumption. Other triggers include severe irritation and bad nutrition. Leukoplakia is more prevalent compared to Erythroplakia. Erythroplakia patches are more often established to be cancerous or precancerous.Visit your dentist for a biopsy in case you notice any red patches that persist for more than a week regardless of whether or not you use alcohol or tobacco.

Lichen Planus

Lichen planus is a term used to refer to a disorder characterized by the occurrence of chronic, irritating and, inflammatory rashes or lesions inside the mouth or on the skin. These lesions may have white spots and those appearing inside the cheeks, on the gums and sides of the tongue may be sore or painful. Lichen Planus is associated with genetics and chronic reaction of the body’s immune system. One is likely to develop Lichen Planus during middle age or at old age. It cannot be transmitted from one person to another and it is also not cancerous.  This condition does not have a cure hence treatment only alleviates pain. Your dentist may recommend topical or systemic medication including rinses, creams, or pills. Correct diagnosis of Lichen Planus is through biopsy and its clinical symptoms. 


Candidiasis is caused by a yeast infection. Other terms used to refer to Candidiasis are moniliasis and oral thrush. Candidiasis forms red and white patches on mouth surfaces. This condition can cause pain, bad breath, interfere with taste buds and problems swallowing. Candidiasis develops the Candida albicans yeast reproduces abnormally in large numbers. This can occur after use of antibiotics, when there is a reduction in the number of helpful bacteria inside the mouth, when body immunity has weakened or due to dry mouth (xerostomia). Usually dry mouth condition is associated with various prescribed and over-the-counter medicines.

Candidiasis is common among children, the old and patients with diseases such as AIDS and diabetes. This condition is also common among denture wearers. Available treatment controls conditions which trigger occurrence. Denture wearers should clean their dentures properly to get rid of Candida and prevent outbreak.

Your dentist may recommend medications for treating dry mouth or saliva substitutes to prevent the mouth from drying. If it is not possible to eliminate the root cause of Candidiasis, your dentist may prescribe anti-fungal medications. 

Oral (mouth) Cancer

Oral cancer can affect the lips, gums, cheek lining as well as the roof and floor of the mouth. Tobacco use contributes to about 70% of all cases of oral cancers. Alcoholic drinks may also increase your susceptibility to oral cancers.

Oral cancer can erupt as a red or white lesion, sore or bump. Initially there is no pain and normally the lesion, sore or bump is small. However it spreads and grows rapidly. Many cancerous sores or lesions can be detected when you go for dental check-ups and so it is advisable that you do regularly. Additionally prevention and treatment of erythroplakia and leukoplakia can prevent some of them from developing into oral cancer. Certain oral cancers may be confused with benign which is harmless hence delaying early diagnosis. You can survive oral cancer and enjoy quality life if the disease is diagnosed and treated early enough. 


  • Visit your dentist regularly for dental examinations. Seek medical help if you have sores that take more than 2 weeks to heal even if you do not experience pain. Usually your dentist conducts a biopsy to establish whether if there is a risk for cancer. A spot or sore can be diagnosed according to where it is located and where it appears.
  • Keep track of the foods and drinks you consume.
  • Keep a record of dental products that you use.
  • Avoid using any form of tobacco.
  • Limit consumption of alcohol.
  • Seek your dentist’s help if you have any sores, spots, patches or bumps whether painful or not.  Oral cancer can be eliminated if it is diagnosed and treated early enough.

In case of any concerns or issues it is always advisable that you bring them to your dentist’s attention.


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