Oral ulcers that appear after biting through the mouth are called traumatic ulcers, and the treatment usually includes removing irritating factors and topical medications, such as compound cortisol and chlorhexidine solution. 1. Remove the irritating factors: the stumpy crowns, sharp tips and edges of teeth, bad restorations, as well as bad habits such as biting lips, cheeks and tongues can lead to oral mucous membrane biting, and it is necessary to prevent the recurrence of traumatic ulcers by grinding and changing the shape of the crowns, modifying restorations, and correcting the bad habits. 2. Local medication: local application of anti-inflammatory and antiseptic drugs such as Compound Cortical Dispersion, Nurturing Yin and Shengmuscle Dispersion, Bingbosan, or gargling Chlorhexidine solution, Compound Boric Acid solution, etc., to prevent secondary infection. All of the above drugs should be used under the guidance of a doctor, and it is recommended to go to a regular medical institution to receive professional treatment.