The posterior molar pad is a soft tissue covering the surface of the posterior triangle of the molar, round or oval in shape, composed of loose fibrous connective tissue and containing a few small salivary glands. In cases of periodontitis of the third mandibular molar, the posterior molar pad is often red and swollen. There are many reasons for the redness and swelling of the posterior pad of the molar, the common reasons and treatment measures are as follows: 1, oral factors 1, wisdom tooth eruption: wisdom tooth is about to erupt will cause swelling of the gums with pain, induced will cause redness and swelling of the posterior pad of the molar, it is recommended to go to the dentist, if it is a mild dental obstruction, you can first pericoronal rinse treatment after observation, if the invasion of surrounding teeth can be considered extraction; 2, wisdom tooth pericoronitis Most of them are caused by incomplete eruption of wisdom teeth, resulting in swelling of gum tissue, severe pain in the posterior region, and in severe cases, increased pain from eating and swallowing. It is necessary to visit the hospital promptly, take oral penicillin and metronidazole combined with anti-inflammatory drugs under the guidance of the doctor, and apply chlorhexidine solution and saline to rinse the posterior cushion area of the molar repeatedly. If there is local abscess formation, incision and drainage and drainage strips should be placed if necessary to avoid the spread of inflammation. Can also wait for inflammation control after surgical extraction and complete treatment; 3, periapical periodontitis: molar gum pus, redness and swelling, chewing discomfort, pain and other symptoms, involving the molar posterior pad, can be used root canal treatment, removal of infection and filling treatment; 4, other: local decay, drug gum hypertrophy, gum tumor and other oral diseases can cause the occurrence of molar posterior pad redness and swelling, it is recommended to perform oral microscopy, x-ray and other examinations to confirm the diagnosis After giving the corresponding correct treatment. Second, nutritional deficiency if the lack of vitamins, folic acid, iron, zinc and other trace elements, will cause oral ulcers, gingivitis, dental caries, etc., inducing the occurrence of post-grinding pad redness, should pay attention to supplement the body required nutrients, enhance immunity. Third, bad habits due to eating spicy and irritating food, as well as not rinsing and brushing on time after meals, will also cause local blood flow obstruction due to food embedding, which will cause redness and swelling of the posterior pad of the molar, should try to eat lightly and maintain good hygiene habits to improve the symptoms. Fourth, primary diseases such as aplastic anemia and thrombocytopenia can also lead to gingival hyperplasia, enlargement and oral mucosal bleeding, thus inducing redness and swelling of the posterior pad of the molar, which should be treated for the primary disease.