When a mouth ulcer heals, a hard lump is left behind, i.e., a scar, which generally does not require special treatment, the scar will gradually fade away, pay attention to daily care and observation can be. Larger mouth ulcers will produce scarring after healing, and most of this scarring will gradually soften and fade over time, without special treatment. Routine daily care includes avoiding rough, too hard and too hot food; balanced nutrition and regular eating habits; ensuring sufficient sleep; maintaining optimism and avoiding anxiety; and maintaining oral hygiene. If scarring persists or other symptoms appear, it is recommended to go to the hospital in time for targeted treatment, such as surgical excision of the scarred area, with the help of the doctor.