There are many causes of acute pharyngocheilitis, such as bacterial infection, viral infection, stimulation of adverse factors and so on. 1. Bacterial infection: Streptococcus pneumoniae, Staphylococcus, Streptococcus infection can induce acute buccal inflammation, especially Group A Streptococcus B infection can cause septic lesions in distant organs, which can induce acute buccal inflammation. 2. Viral infection: many kinds of bacteria can induce acute buccal inflammation, such as adenovirus, coxsackie virus, parainfluenza virus, etc. These viruses can be spread through close contact, droplet and other ways. 3. Stimulation of adverse factors: dry environment, smoke, dust, and allergen stimulation can also induce acute buccitis. There are many reasons for acute buccitis, and after symptoms appear, it is recommended to go to the hospital in time to improve the examination and take standardized treatment according to the doctor’s instructions.