When dentures make your gums sore: when to adjust them and insurance-covered maintenance

When a denture presses on or rubs the gum, the spot turns red and swollen, and a white raw sore forms that hurts with every bite. In Korea, Seoul National University Hospital's medical information advises cleaning dentures thoroughly and taking them out of the mouth during sleep, and the National Health Insurance Service (NHIS, 국민건강보험공단) provides a free check period and maintenance coverage after fitting for insurance-covered dentures. The sore usually improves once the spot where the denture does not fit is adjusted, so rather than putting up with it, it is better to have the sore spot checked at the dentist.

Published 2026-11-08 · Updated 2026-11-08 · DentalStatics editorial team

Key facts

Why do dentures cause sores in the mouth?

A denture sits on the gum and passes biting force to the gum. If the inner surface of the denture is even slightly off from the shape of the gum, force concentrates at certain points and they become red, swollen and raw. Such sores are common in the period when a new denture is first worn.

Sores can also form with a denture used for a long time. As time passes, the shapes of the gum and the bone beneath it change little by little, and the denture may loosen or press hard on one side. The maintenance items for dentures at NHIS include modification of the tissue surface of the denture, such as relining, rebasing and tissue conditioning, in order to refit the inner surface of the denture to the changed gum.

Dry mouth also adds to denture discomfort. The dry mouth information on the National Health Information Portal explains that when the mouth is dry it can be hard to manage a denture, so if your mouth is often dry, drink water in small amounts often and also check the cause of the dry mouth.

What other changes in the mouth should be checked besides denture sores?

People who wear dentures easily get oral candidiasis. The National Health Information Portal names denture use as a trigger of oral candidiasis, and Seoul National University Hospital's medical information explains that candidiasis easily develops with poorly cleaned dentures. If the whole gum that the denture touches turns red or the corners of the mouth become raw, a fungal infection is also suspected.

If a lump-like swollen tissue forms where the denture edge touches, the sore turns hard, or the denture suddenly stops fitting well, do not put off an exam. The National Cancer Information Center of the National Cancer Center explains that a lump in the mouth can make a denture fit poorly, and recommends a biopsy for an ulcer that does not heal and stays for more than 3 weeks.

What should I do when a denture sore forms?

When a sore spot forms, the principle is to have the denture adjusted at the dentist rather than putting up with it and keeping it in. Wearing the denture to the visit on the day makes it easier to see which part is pressing on the gum. However, if the pain is too severe to wear it, do not force it; bring the denture and consult.

While the sore is healing, cut back on foods that irritate it, such as salty and spicy foods, and after meals take the denture out, wash it and rinse the mouth. Avoid grinding the inside of the denture yourself with a knife or sandpaper, as this can ruin the denture and make the fit worse. If you have to leave the denture out for a while because of the sore, eat soft foods and have it adjusted at the dentist before putting it back in.

How do I get adjustments and maintenance for insurance-covered dentures?

According to NHIS, for people aged 65 and over who have been fitted with an insurance-covered denture, follow-up checks can be received up to 6 times in the 3 months after fitting by paying only the exam fee with no procedure fee. A sore from a new denture can be adjusted in this period to reduce the cost burden.

Maintenance after the free period ends is also covered by health insurance, with a copayment of 30%, and a lower rate applies to the near-poor and medical aid recipients. Each item has a recognized number of times per year: denture base adjustment and tissue conditioning are each recognized up to 2 times a year, and relining by the direct method and by the indirect method up to 1 time a year each; beyond the count, you pay the full cost yourself. Whether you are eligible and how many recognized counts are left this year can be confirmed by asking the dentist or NHIS.

How should I care for dentures to prevent sores?

Denture care habits based on material from Seoul National University Hospital, the Korea Disease Control and Prevention Agency and the Ministry of Food and Drug Safety are as follows. The dry mouth information on the National Health Information Portal advises disinfecting dentures every day so that mold does not grow. Small daily habits reduce both gum sores and fungal infection.

• Take dentures out when sleeping, and store cleaned dentures soaked in cold water
• Dissolve cleanser in lukewarm water of 30 to 40 degrees C and follow the product instructions for soaking time
• Do not use salt water, hot water above 60 degrees C or toothpaste to clean dentures
• Take dentures out after meals to wash them and rinse the mouth
• Gently brush the gum and tongue where the denture was removed
• Even when nothing hurts, have the fit checked at the dentist regularly

Common myths and facts

Frequently asked questions

Related topics

• Mouth sores and oral pain
• Mouth sores and oral pain
• Oral candidiasis
• Ulcer that won't heal
• Mouth sore care

References

1. NHIS Elderly Denture Coverage Guide
2. Korean Dental Association Notice: Ministry of Food and Drug Safety on Proper Use of Denture Cleanser
3. Seoul National University Hospital N Medical Information: Stomatitis
4. KDCA National Health Information Portal: Dry Mouth
5. National Cancer Information Center, National Cancer Center: Oral Cancer

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