Many other types of lesions can be seen in the mouth including infectious or inflammatory lesions, benign (noncancerous) and precancerous tumors, cancers, and even irregularities that can be considered normal. Some examples of other oral lesions include:

Leukoplakia—Leukoplakia is a thick, white-colored patch that forms on the inside of the cheeks, gums, or tongue. These patches are caused by excess cell growth and are common among tobacco users. They can result from irritations such as ill-fitting dentures or the habit of chewing on the inside of the cheek. Leukoplakia can progress to cancer.

Candidiasis—Candidiasis, or oral thrush, is a fungal infection that occurs when yeast reproduce in large amounts. It often causes white plaques that can be scraped off to reveal tender red areas underneath. It is common among denture wearers and most often occurs in people who are very young, elderly, debilitated by disease, or who have a problem with their immune system. People who have dry mouth syndrome or use oral steroid inhalers for asthma are also susceptible to the infection. Candida may flourish after antibiotic treatment, which can decrease normal bacteria in the mouth.

Hairy tongue—Hairy tongue is a harmless condition that causes the top of the tongue to develop a furry yellow to dark brown coating. It is caused by the buildup of dead skin on tiny projections, or papillae, that cover the top of the tongue. Poor oral hygiene, chronic oral irritation, or smoking can cause this condition. Hairy tongue is often treated with a toothbrush or special tongue scraper to help remove the dead skin.

Torus palatinus—Torus palatinus is a hard, bony growth in the center of the roof of the mouth (palate).  It commonly occurs in early adulthood, more often in women. Both environmental factors, such as teeth grinding, and genetic factors may contribute to its formation. While rarely needing treatment, a torus palatinus may be removed in order to fit dentures properly.

Mucocele—Mucoceles are soft mucous-filled nodules that are commonly found on the inside of the lower lip. These usually occur from a bite to the lip that injures a minor salivary gland, causing a spillage of mucous and creating a small lump. Mucoceles can rupture or “pop” but often come back.

Oral cancer—Oral cancer may appear as a white or red patch of tissue in the mouth, or a small ulcer that looks like a common canker sore. Other than the lips, the most common areas for oral cancer to develop are on and under the tongue. Other symptoms include a firm lump or mass that can be felt inside the mouth or neck; pain or difficulty with swallowing, speaking, or chewing; any wart-like mass; hoarseness that lasts for more than two weeks; or any numbness in the oral/facial region.

Dental trauma—Injury to the teeth, gums and/or nearby soft tissue such as the lips and tongue can cause a mouth sore, for instance, accidentally biting the inside of your mouth or cheek.