Question 1

What are mouth ulcers?

Accepted Answer

Mouth ulcers are small, painful sores that develop on the inside of the mouth—such as cheeks, gums, tongue, or inner lips. They often appear round or oval with a white or yellow center surrounded by a red border. Most heal on their own within about 1–2 weeks.
Source: Mayo Clinic (Canker sore – symptoms, causes, 2018)

Question 2

What causes mouth ulcers?

Accepted Answer

Common causes include local trauma (e.g., from sharp foods, dental appliances, or accidental biting), stress, and nutritional deficiencies such as low iron or vitamin B12. In many cases, the exact cause remains unknown.
Source: Porter?SR?et?al., Recurrent aphthous ulcers, PMC NCBI (2007)

Question 3

Can mouth ulcers be contagious?

Accepted Answer

No—most mouth ulcers, like canker sores (aphthous ulcers), are not contagious. Ulcers caused by viral infections (such as those from herpes simplex virus) can be contagious, but these are distinct from canker sores.
Source: NIDCR/NIH (Fever Blisters & Canker Sores overview, 2023)

Question 4

Can mouth ulcers get infected?

Accepted Answer

Yes. Mouth ulcers may become secondarily infected if bacteria invade the sore, especially when oral hygiene is poor. Signs may include increased pain, swelling, pus, or fever, warranting medical evaluation.
Source: Mayo Clinic (Canker sore – treatment section, 2018)

Question 5

What do mouth ulcers look and feel like?

Accepted Answer

Mouth ulcers typically appear as round or oval sores with a white or grayish center and a red outer ring. They may feel sore, sensitive, or painful-especially when eating, drinking, or brushing teeth.

Question 6

Can a mouth ulcer cause bad breath or discomfort?

Accepted Answer

Yes, mouth ulcers can contribute to bad breath (halitosis) due to inflammation and bacterial activity. They may also cause discomfort while talking or eating spicy, acidic, or rough foods.

Question 7

Why do mouth ulcers happen repeatedly?

Accepted Answer

Recurring mouth ulcers may be linked to stress, nutritional deficiencies, hormonal shifts, certain medications, or conditions like celiac disease or Crohn’s disease. Frequent outbreaks should be discussed with a healthcare professional.

Question 8

Are mouth ulcers spread through contact?

Accepted Answer

Non-infectious ulcers like canker sores are not spread through kissing or sharing utensils. However, viral mouth ulcers-such as those caused by herpes-can spread through direct oral contact.

Question 9

What causes a mouth ulcer to heal slowly?

Accepted Answer

Ulcers may heal slowly due to poor oral hygiene, ongoing irritation, stress, smoking, or an underlying health condition. Vitamin deficiencies or an impaired immune response can also delay healing.

Question 10

What treatments help mouth ulcers heal faster?

Accepted Answer

To promote healing, maintain good oral hygiene, avoid spicy or acidic foods, and use soothing remedies like saltwater rinses or over-the-counter gels. If ulcers persist beyond two weeks or worsen, seek medical advice.

Mouth Ulcer Medications