Recurrent aphthous ulcerations. American Academy of Oral and Maxillofacial Pathology. http://www.aaomp.org/public/aphthous-ulcerations.php. Accessed Feb. 15, 2015.

The most common oral ulcer is one caused by trauma. This trauma is most often mechanical (eg biting) but may also be from thermal, radiation or chemical means. The characteristic symptoms of inflammation, pain, redness and swelling are often present, and the central part of the ulcer may be covered by a yellow-white fibrinous exudate (Figure 1). Common infections causing mouth ulcers include the Herpes simplex virus, and those infections associated with Hand, foot and mouth disease There are many causes of oral ulcers, as highlighted in the 'overview of oral lesions' at the top of this sectionOral lichen planus. This condition can cause itchy rashes and lacelike, white sores inside your mouth. Oral lichen planus is an immune system response and most commonly affects women and people assigned female at birth (AFAB) age 50 or older. If local treatments are not adequate add in a trial of colchicine 500 mcg tablets OD, then increase to BD, occasionally TDS is used if the patient it able to tolerate it, however, it can take 4-6 months for colchicine to take effect However, treatment can help to reduce swelling and ease any discomfort. This may help if you keep getting mouth ulcers or your mouth ulcer affects eating and drinking. Self care If you have symptoms of mouth cancer, your GP will carry out a physical examination and ask about your symptoms. A broken area in the lining of the mouth (ulcer) that will not heal is a common symptom of mouth cancer. Pain in your mouth

Figure 16. Erythroplakia of the bilateral floor of the mouth presenting as a diffuse, painless, ‘velvety’ red patch. This lesion harboured severedysplasia. Lichen planus (an inflammatory condition that appears as a rash on the inside of your mouth and other parts of the body) A folate deficiency is caused by not having enough folate, also known as vitamin B9. Folate is an important B vitamin used to make and repair DNA. It’s critical to proper development in embryos. Being deficient in folate can also lead to folate deficiency anemia. Your genes are also thought to have a role. Around 40% of people who keep getting mouth ulcers report that it runs in their family. Medical conditions There are several types of canker sores, including minor, major and herpetiform sores. Minor canker sores

Hairy leukoplakia

The exact cause of mouth ulcers is still not known and varies from person-to-person. Still, there are some common causes and several factors that may aggravate mouth ulcers, including the following: Linden J, et al. (2017). Frequency of visits and examinations in the Public Dental Service in Finland – a retrospective analysis, 2001–2013. Gupta PC, Murti PR, Bhonsle RB, Mehta FS, Pindborg JJ. Effect of cessation of tobacco use on the incidence of oral mucosal lesions in a 10-yr follow-up study of 12,212 users. Oral Dis 1995;1(1):54–58. doi: 10.1111/j.1601-0825.1995.tb00158.x. Search PubMed

While mouth ulcers are very common and normally clear up on their own, they can be uncomfortable and irritating. They're small sores (or lesions) that can appear anywhere in the mouth and may take a week or two to heal. Holmstrup P. Oral erythroplakia – What is it? Oral Dis 2018;24(1–2):138–43. doi: 10.1111/odi.12709. Search PubMed There are a number of things that can lead to mouth sores. Causes range from common injuries to serious health conditions. Common mouth sore causes include: Tobacco use, particularly smokeless tobacco, puts you at high risk of leukoplakia and oral cancer. Long-term alcohol use increases your risk, and drinking alcohol combined with smoking increases your risk even more. Hairy leukoplakiaBoth alcohol and tobacco are carcinogenic, which means they contain chemicals that can damage the DNA in cells and lead to cancer. Some people confuse canker sores with cold sores (fever blisters), but they’re very different. A canker sore appears inside your mouth. A cold sore forms outside your mouth, usually on your lips. Canker sores aren’t contagious, but cold sores are. How do you know if your mouth ulcer is bad? Your specialist nurse and your GP can provide help and support if you are finding it difficult to quit smoking and drinking. A white or grayish patch inside your mouth or on your lips is called leukoplakia. The patches may be rough and hard and difficult to scrape off.