Most gum sores heal on their own within one to two weeks, and simple home treatments can reduce pain and speed the process along. The right approach depends on what type of sore you’re dealing with, whether it’s a canker sore, a blister caused by physical trauma, or something that needs professional attention.
Identify What Kind of Sore You Have
A sore inside your mouth on the gums, cheeks, or tongue is most likely a canker sore. These appear as a single round white or yellow spot with a red border. They’re not contagious, and their exact cause isn’t fully understood, though they can be triggered by injury (like biting your cheek or brushing too hard), stress, smoking, or nutritional deficiencies in B12, iron, or folate.
Cold sores are different. They show up as clusters of small fluid-filled blisters, typically on the outside of the mouth around the lip border. They’re caused by the herpes simplex virus and are contagious. If your sore is inside your mouth on the gum tissue and looks like a shallow ulcer rather than a blister, you’re almost certainly dealing with a canker sore or a wound from physical irritation.
Salt Water Rinse
A warm salt water rinse is the simplest and most effective first step. Mix 1 teaspoon of salt into 8 ounces of warm water, then swish it around your mouth for 15 to 30 seconds before spitting it out. If it stings too much, cut the salt down to half a teaspoon. You can repeat this several times a day, especially after meals. Salt water helps draw fluid out of the swollen tissue, reduces bacteria around the sore, and creates a cleaner environment for healing.
Over-the-Counter Pain Relief
For sores that make eating or talking painful, a topical numbing gel can help. Products like Orajel contain 20% benzocaine, which temporarily numbs the area on contact. Apply a small amount directly to the sore up to four times a day. The relief is short-lived, usually lasting 20 to 30 minutes, but it can make mealtimes more manageable.
You can also find OTC mouth rinses containing hydrogen peroxide, which help keep the sore clean. Avoid mouthwashes with alcohol, as they tend to burn and can irritate the tissue further.
Other Home Remedies Worth Trying
Placing a small amount of milk of magnesia directly on the sore a few times a day can coat it and reduce pain. Some people find relief by holding a damp tea bag against the sore for a few minutes, since tea contains tannins that have mild astringent properties. Ice chips or cold water held against the gum can also temporarily numb the area.
What you avoid matters as much as what you apply. Spicy foods, acidic fruits like oranges and tomatoes, and crunchy or sharp-edged snacks like chips can all aggravate a gum sore and slow healing. Stick with softer, blander foods until the sore closes up.
Toothpaste May Be Making It Worse
Many common toothpastes contain sodium lauryl sulfate (SLS), a foaming agent that can strip the delicate lining of your mouth and irritate open sores. Research published in the British Dental Journal found that SLS can cause oral tissue peeling and increase the frequency of recurring mouth ulcers in people who are prone to them. If you get gum sores regularly, switching to an SLS-free toothpaste is one of the easiest changes you can make. Several brands market SLS-free formulas specifically for sensitive mouths.
Nutritional Deficiencies and Recurring Sores
If you keep getting sores on your gums, your diet may be a factor. Deficiencies in vitamin B12 and folate are strongly linked to recurrent canker sores. In one case-control study of 40 people with recurring mouth ulcers, 75% had low levels of B12 or folate. Both of these nutrients play a direct role in maintaining the lining of your mouth. When levels drop, the tissue becomes fragile and prone to breaking down into ulcers.
B12 is found in meat, fish, eggs, and dairy. Folate is abundant in leafy greens, beans, and fortified grains. If you eat a restricted diet, or if sores keep coming back despite good oral hygiene, a blood test can check whether a deficiency is driving the problem. Supplementation, when a deficiency is confirmed, often reduces or eliminates recurrences.
Normal Healing Timeline
Minor canker sores, the kind smaller than a pea, typically heal within a few weeks without leaving a scar. They tend to hurt the most during the first three to four days and then gradually improve. Major canker sores, larger than about one centimeter, are a different story. They can be extremely painful, take months to fully heal, and sometimes leave scar tissue behind.
If a sore on your gum hasn’t healed after two weeks, that’s the point where you should get it looked at by a dentist or doctor. A sore that lingers beyond that window may need a biopsy to rule out other conditions, including oral cancer, especially if it’s painless, firm, or irregularly shaped.
Signs That Need Immediate Attention
Some gum sores are not routine ulcers. A dental abscess, which is a pocket of infection at the root of a tooth or in the gum tissue, produces very different symptoms: a throbbing pain that radiates into the jaw, swelling in the face or cheek, tender lymph nodes under the jaw, fever, and sometimes a sudden rush of foul-tasting salty fluid if the abscess ruptures on its own.
An abscess will not heal with home remedies. It requires professional drainage and typically antibiotics. If you have facial swelling combined with a fever, or if the swelling makes it hard to breathe or swallow, that’s an emergency. The infection can spread into the jaw, throat, or neck and become dangerous quickly.
What a Dentist Can Do
For sores that are severe, large, or keep coming back, a dentist has options beyond what’s available over the counter. Prescription-strength corticosteroid rinses can reduce inflammation and pain more effectively than OTC products. For especially stubborn or painful sores, laser treatment can remove the lesion and promote faster healing, often with immediate pain relief. Silver nitrate cauterization is another in-office option that chemically seals the sore to reduce pain and shorten healing time.
If your sores are linked to a sharp tooth edge, a rough filling, or ill-fitting dentures that keep irritating your gums, fixing the source of the trauma is the most effective long-term treatment. No amount of rinse or gel will help if the tissue keeps getting re-injured in the same spot.