Recurrent oral ulcers are recurrent, limited ulcerative diseases of the oral mucosa caused by a variety of factors. The incidence is about 20%, ranking first in oral mucosal diseases. Recurrent oral ulcers mostly occur on the inner lip, tongue tip, tongue edge, tongue belly or buccal mucosa. Initially, the lesion appears as a small red spot with spontaneous mild tingling and burning sensation and other pre-symptoms; subsequently, ulcers are formed. With the development of the disease, the ulcer gradually expands from the inside out, the surrounding mucous membrane is congested and red, and the surface is covered with a yellowish fibrous membrane, the pain is intense at this time, and the pain increases after contact with irritating food, which affects eating. The number of ulcers varies and can heal on its own in 7-10 days, and can recur after an interval. The length of the interval varies from a few days to several months. In severe cases, the number of ulcers increases, accompanied by systemic symptoms such as enlarged submandibular lymph nodes and fever. Recurrent mouth ulcers can be divided into three categories: light, heavy, and rash-like. The light type is the most common, with 1 to 5 ulcers each time and 2-4 mm in diameter. The heavy type is characterized by large and deep ulcers, resembling “craters”, with a diameter of 10-30 mm. Pimple-like ulcers appear as a dozen or so small ulcers of 1-2 mm diameter appearing simultaneously or sequentially on the oral mucosa. Based on the self-healing and self-limiting characteristics of recurrent oral ulcers, the treatment is mainly local and supplemented by systemic treatment. Local treatment is based on the principles of anti-inflammation, antisepsis, pain relief and promotion of ulcer healing, and patients can choose pain-relieving tablets, dispersions or anti-inflammatory films and other fast-acting and simple local application drugs. Systemic treatment can take prednisone (prednisone), diphenhydramine and other adrenal cortical solid intoxication, or injection of transfer factor, gammaglobulin and other drugs to enhance immune function. In case of combined bacterial infection, antibacterial drugs can be used in combination. In recent years, laser, freezing, microwave and other new technologies are also used to treat day cavity ulcers, and achieve certain efficacy. 1.What factors are related to the development of recurrent oral ulcers? The etiology of recurrent oral ulcers is still inconclusive and is generally considered to be multifactorial, mainly related to viral or bacterial infections, digestive disorders, abnormal immune function, microcirculatory disorders, zinc, iron, vitamin B: deficiency, endocrine factors, genetic factors and mental factors. More and more scholars tend to believe that oral ulcer is an autoimmune disease, i.e., genetically susceptible persons under the influence of the above mentioned triggers make the said membrane resistance decrease, and when the body is stimulated by a certain antigen, autoimmune damage occurs. A considerable number of patients with recurrent aphthous ulcers are accompanied by gastrointestinal diseases, such as gastritis, gastric ulcer, duodenal ulcer, constipation or diarrhea, etc. These diseases have recurrent characteristics, so that oral ulcers also show periodic characteristics. 2 .What are the common drugs used to treat recurrent mouth ulcers? When ulcers occur, you can use anti-inflammatory, anti-swelling, pain relief, promote the healing effect of ulcers gargle or topical drugs for local treatment, the better effect of drugs such as beads yellow powder, Panax notoginseng powder, watermelon cream, pearl powder. When using topical medicine, first wash the mouth with mouthwash, especially the affected part, remove food residue, saliva, etc., and use a clean cotton swab to wipe dry the topical medicine, so that the medicine is directly attached to the ulcer surface. Among them, film agent is more commonly used, it is a polymer material as a matrix, adsorbed one or several kinds of drug ingredients. It can firmly adhere to the ulcer surface for a long time, allowing it to play the role of anti-inflammatory, antiseptic, pain relief and promote healing, such as can be paste. 3.What kind of mouth ulcer will have the possibility of cancer? If the mouth ulcer cannot heal itself in 1 month, or cannot be cured after half a month of medication. It is necessary to seek medical examination. Especially if the ulcer surface has “cauliflower-like” or “crater-like” changes, if there is also bad breath, bleeding gums, swollen local lymph nodes and local discomfort, it should be alert enough to go to the hospital immediately for relevant examination. 4.How to prevent mouth ulcers? Look for triggers and actively avoid them in order to reduce the frequency of ulcers. In daily life, pay attention to maintaining a clean mouth and avoiding damage to the oral mucosa; combine work and rest, keep your mood relaxed and avoid excessive fatigue and tension; pay attention to the regularity of life and balanced nutrition, quit smoking and drinking, adhere to physical exercise; eat a light diet, eat more vegetables and fruits, drink more water and keep bowel movements smooth.