Mouth sores and oral lesions can develop inside the mouth, on the lips, or on the tongue. Many are harmless and resolve on their own within several days or a couple of weeks. Others may require professional evaluation or treatment.
Understanding what caused the sore, how long it has been present, and whether it is changing can help determine whether it is a minor concern or something that should be examined by a dentist.
What are some of the most common sores seen in people's mouths?
Canker sores are among the most common mouth sores. They can develop almost anywhere inside the mouth and may be very painful.
A canker sore may begin as a small tender area before developing into a whitish or grayish spot surrounded by red, irritated tissue. Most canker sores heal on their own within approximately one to two weeks.
Cold sores are another common type of oral lesion. They usually develop around the lips or corners of the mouth and are caused by a viral infection. Cold sores are also generally self-limiting, but antiviral creams or oral medications may help reduce their severity and shorten the outbreak when treatment begins early.
What else can cause sores in your mouth?
Traumatic irritation can also cause mouth sores or tissue changes. Biting the inside of your cheek or lip, brushing too aggressively, or repeatedly rubbing the same area can create a white patch or irritated lesion.
Many of these areas are harmless, but some can resemble more serious conditions, including oral cancer. Any persistent or changing patch should be evaluated during a dental examination.
Dental appliances can also irritate the tissues inside the mouth. Common examples include:
- Dentures
- Clear aligners
- Orthodontic retainers
- Night guards or other oral appliances
If an appliance has a rough or sharp edge, it may repeatedly rub against the cheek, tongue, lips, or gums. Contact Matheson Dentistry & Implant Center so the appliance can be evaluated and adjusted.
Why is it important to get mouth lesions checked?
Dentists are trained to evaluate sores, patches, lumps, and other changes involving the tissues of the mouth. Many lesions have a familiar appearance and can be identified as minor or self-limiting during an examination.
If an area looks unusual or concerning, a biopsy may be recommended. During a biopsy, the area is numbed and a small sample of tissue is removed. The sample is then sent to a pathology laboratory and examined under a microscope.
A biopsy can help determine whether the lesion is benign, inflammatory, infectious, precancerous, or cancerous. If you have a persistent or unusual oral lesion, Matheson Dentistry & Implant Center can evaluate the area and determine whether further testing is appropriate.
Are mouth sores contagious?
Some mouth sores are contagious, while others are not. Cold sores around the lips are caused by a virus and can spread to another person, particularly when a blister or active sore is present.
During a cold sore outbreak, avoid kissing, sharing drinks or utensils, and having close contact with babies or people with weakened immune systems.
Canker sores, traumatic sores, and irritation caused by dental appliances are not contagious.
Can you still go to the dentist if you have a mouth sore?
In many cases, you can still attend a dental appointment when you have a mouth sore. Dental professionals use standard infection-control precautions, including gloves, masks, and protective eyewear.
However, the location and severity of the sore may make treatment uncomfortable. An active cold sore may also affect whether certain procedures should be postponed. Contact the office before your appointment so the dental team can advise you based on your symptoms and planned treatment.
What happens during an oral cancer screening?
During an oral cancer screening, the dentist examines areas where oral lesions commonly develop, including:
- The top, sides, and underside of the tongue
- The floor and roof of the mouth
- The inside of the cheeks and lips
- The gums and throat
- The areas around the lips and jaw
If we find an area that needs to be monitored, we may take a photograph and document its size, shape, color, and location. This allows us to compare the lesion over time.
A lesion that grows, changes shape or color, bleeds, becomes firm, or does not heal may require a biopsy or referral for additional evaluation.
How can you tell if a mouth sore is minor or more concerning?
A mouth sore may be less concerning when there is an obvious explanation, such as accidentally biting your cheek, irritating the area with a toothbrush, or being rubbed by a dental appliance.
Minor traumatic sores should gradually improve once the source of irritation is removed. A sore is more concerning when it:
- Has no clear cause
- Does not improve within one to two weeks
- Continues to grow or change
- Bleeds repeatedly
- Feels hard or firm
- Causes increasing pain or difficulty swallowing
If you are unsure why an oral lesion developed or it is not healing, schedule an evaluation with Matheson Dentistry & Implant Center.
When should a mouth lesion be biopsied?
A biopsy may be recommended when a mouth lesion does not heal within approximately one to two weeks, has no obvious cause, or has features that appear unusual during an examination.
Not every persistent lesion requires a biopsy, but it should be professionally evaluated. The dentist will consider its appearance, location, texture, symptoms, and how long it has been present before recommending the next step.
What can you do for canker sores?
Most canker sores heal without treatment. While they are healing, warm salt water rinses may help soothe the area and keep the mouth clean.
Other treatment options may include:
- Over-the-counter numbing gels
- Prescription mouth rinses
- Compounded rinses such as Magic Mouthwash
- Topical steroid medications for more severe or recurring sores
- Oral medication in uncommon, severe cases
The right treatment depends on how painful, frequent, or widespread the sores are.
What is the difference between canker sores and cold sores?
Canker sores and cold sores have different causes and usually develop in different locations.
Cold sores generally appear on or around the lips and are caused by a virus. They are contagious and may be treated with antiviral medication.
Canker sores develop inside the mouth and are not contagious. Their exact cause is not always clear, but outbreaks may be associated with stress, minor injuries, certain foods, or changes in the immune system.
Because the treatments are different, it is important to identify which type of sore you have before beginning medication.
What should you do if you have a sore in your mouth that is not healing?
If a sore on your lips, tongue, gums, cheeks, or elsewhere in the mouth does not heal within one to two weeks, schedule an examination with Matheson Dentistry & Implant Center.
We can evaluate the area and determine whether it appears benign, needs continued monitoring, or should be biopsied. Early evaluation is particularly important when a lesion is growing, changing, bleeding, or becoming increasingly painful.
Can dental infections cause mouth sores?
Yes. A dental infection can sometimes create a small bump, pimple-like sore, or area of swelling on the gums near the affected tooth. This may be a drainage point from a dental abscess.
Treating the sore alone will not resolve the problem because the infection is coming from the tooth or surrounding tissues. If you notice a gum sore near a painful, sensitive, broken, or previously treated tooth, contact Matheson Dentistry & Implant Center for an evaluation.
If you’re searching for quality dental care, we’re here to help. Call (480) 888-8123 or email [email protected] to schedule your visit. Our team is committed to keeping your smile healthy.