A mouth ulcer is a painful sore that develops inside the mouth, making simple activities like eating, drinking, and speaking uncomfortable. These sores can appear on the gums, tongue, inner cheeks, inner lips, and roof of the mouth. They are usually red, yellow, or white and may appear alone or in clusters.

Although mouth ulcers can be distressing, they are not contagious and do not spread through kissing, sharing food, or drinks. Most heal on their own within a week or two. However, persistent or recurring ulcers may indicate underlying health issues such as autoimmune disorders, viral infections, or digestive conditions.

Types of Mouth Ulcers
Mouth ulcers vary in cause and severity. Some of the most common types include:

Canker Sores (Aphthous Ulcers): The most common type, often triggered by stress, acidic foods, or minor injuries like cheek biting. They appear white or yellow with a red border.

Oral Lichen Planus: An immune response condition that creates white, lace-like sores in the mouth, mainly affecting women over 50.

Leukoplakia: White or gray patches caused by excessive cell growth, often linked to smoking or tobacco use. Though usually benign, they require monitoring.

Erythroplakia: Red patches that may indicate precancerous or cancerous changes, often associated with tobacco use.

Oral Thrush: A fungal infection caused by an overgrowth of Candida albicans, often triggered by weakened immunity or antibiotic use. It results in creamy white or red sores.

Mouth Cancer: A serious condition where ulcers do not heal. A healthcare provider should examine any sore lasting more than three weeks.

Symptoms of Mouth Ulcers
Mouth ulcers are easy to recognize by their distinct appearance and discomfort. They typically have:

• Red edges with a white, yellow, or gray center
• Swelling around the sore
• Pain, especially when eating spicy, salty, or sour foods
• Increased sensitivity when brushing teeth

What Causes Mouth Ulcers?
Several factors can contribute to mouth ulcers, including:

• Accidental injury (cheek biting, dental work, braces)
• Allergic reactions to bacteria
• Acidic foods (oranges, pineapples, strawberries)
• Hormonal changes (such as during menstruation)
• Stress and lack of sleep
• Harsh toothpaste or mouthwash

Why It Matters
While most mouth ulcers heal naturally, frequent or persistent sores should not be ignored. They can signal underlying health concerns that require medical attention. Maintaining good oral hygiene, reducing stress, and avoiding irritants can help prevent them. If an ulcer doesn’t heal after three weeks, a healthcare provider should evaluate it.