Lifestyle

Mouth Sores That Don’t Heal Can Be an Early Sign of Oral Cancer. Other Signs Dentists Look For

By Erica Coleman · November 1, 2026

A mouth sore is easy to shrug off. One that is still there after two weeks deserves a closer look.

The National Institute of Dental and Craniofacial Research says that if you have any of the warning signs of oral cancer for more than two weeks, see a dentist or a doctor. Oral cancer includes cancers of the mouth and the back of the throat, according to the institute, and it most often occurs in people over 40.

Age is a big part of the picture. The American Cancer Society says the average age of people diagnosed with oral cavity and oropharyngeal cancers is 64, and these cancers are more than twice as common in men as in women. The society estimates about 60,480 new cases in the United States in 2026.

These are signs listed by the cancer society and the NIDCR. Many can be caused by something other than cancer, the cancer society notes, but if any of them last more than a few weeks, it says it is very important to see a doctor or dentist.

A sore that doesn’t heal. The cancer society lists a sore on the lip or in the mouth that doesn’t heal, along with mouth pain that doesn’t go away.

A white or red patch. Look for patches on the gums, tongue, tonsils or lining of the mouth, according to the cancer society.

A lump or thick spot. The NIDCR lists a lump or thick patch in the mouth, lip or throat, and a lump in the neck.

Dentures that start to fit poorly. Swelling of the jaw can make dentures fit badly or become uncomfortable, the institute says. The cancer society also lists loose teeth or pain around the teeth.

Trouble chewing, swallowing or talking. The NIDCR includes difficulty moving the jaw or tongue, a persistent sore throat, a feeling that something is caught in the throat, and hoarseness.

Numbness, bleeding or ear pain. The institute lists numbness in the tongue or other areas of the mouth, pain or bleeding in the mouth, and ear pain. The cancer society adds voice changes and weight loss.

Tobacco and alcohol drive much of the risk. The NIDCR says most cancers in the mouth are related to tobacco use, drinking alcohol or both, while most throat cancers are caused by HPV. The cancer society says smoking and drinking alcohol together multiplies the risk, and people who drink and smoke heavily have about 30 times the risk of people who do neither. Quitting tobacco greatly lowers the risk, the society says, even after many years of use.

The society says many studies have found no higher risk in denture wearers overall, but it advises having dentures checked regularly by a dentist for fit and taking them out at night to clean them.

There is no routine screening test. The cancer society says doctors in the United States don’t recommend routine screening for these cancers, but many pre-cancers and cancers in the mouth and throat are found early by self exam or during routine oral exams. It says some dentists suggest checking your mouth in a mirror every month for white patches, sores or lumps, especially if you use tobacco or drink regularly.

The NIDCR says the oral cancer exam is painless and takes only a few minutes, and a regular dental checkup is an excellent time to have it. During the exam, a dentist or hygienist checks the face, neck, lips, entire mouth and back of the throat.

This article is for general information and is not medical advice. See a dentist or doctor about any mouth sore, patch or lump that lasts more than two weeks. This article was produced with the assistance of AI and fact-checked against the sources cited by LightWave Reports.