Oral health is fundamental to overall well-being. Proper oral care extends far beyond clean teeth and a bright smile—it is about protecting the body from infections and inflammation that can have far-reaching effects on your health.

Among the most common and bothersome oral issues are canker sores—small ulcers that, despite their size, can greatly affect daily life. These painful lesions develop on the soft tissues inside the mouth, particularly on the tongue, the inner cheeks, the gums, or the soft palate.

While not contagious, they are generally quite uncomfortable and can make basic activities like eating or speaking difficult. Canker sores, also known as aphthous ulcers, have a typical appearance: small, roundish erosions with a whitish or yellowish center surrounded by a red halo. Unlike viral infections like herpes, they don’t spread from person to person and don’t affect the outside of the lips—they occur exclusively inside the mouth.

There are many interconnected causes that contribute to their appearance. According to the Italian National Institute of Health and the Ministry of Health, there is no single explanation for the development of canker sores, but several factors appear to play a role.

Physical and emotional stress both play a role, as does minor mouth trauma—such as aggressive brushing, accidentally biting the inside of the cheek, a scratch from a chipped or sharp tooth, or an ill-fitting dental prosthesis. Nutritional deficiencies, particularly in vitamins, can also weaken the oral mucosa and increase vulnerability to these ulcers.

Other potential triggers include immune system irregularities and sensitivities to certain foods—chocolate, citrus, spicy dishes, and acidic items are common offenders. Hormonal fluctuations can sometimes be a contributing factor as well.

In most cases, canker sores heal on their own within a week to ten days. During this time, even though healing occurs naturally, it is helpful to manage the pain by avoiding acidic or salty foods and other irritants. Applying specific products like gels, mouthwashes, or anti-inflammatory and anesthetic agents can help speed up recovery. It is also important to maintain proper oral hygiene and try to reduce stress as much as possible.

Certain warning signs, however, should not be ignored. When canker sores become unusually large, painful, or frequent or fail to heal within two weeks, medical attention is warranted. The same applies if they are accompanied by other symptoms such as fever, joint pain, or gastrointestinal issues. In such cases, consulting a specialist can help rule out more serious underlying conditions and determine whether further diagnostic testing is necessary.