The swelling of one side (one side) of the cheek should consider the following possibilities: 1. Oral inflammation: If the patient has toothache itself, pay attention to whether there is periodontitis, periapical inflammation and pericoronitis of wisdom teeth, if this condition exists, antibacterial medication is needed, together with anti-anaerobic medication, and also treatment by a dentist for the tooth itself; 2. Osteomyelitis caused by radiotherapy: If the patient has history of tumor, after radiotherapy treatment, there is an enlargement of one side of the cheek, also pay attention to whether there is inflammation of bone marrow, because radiotherapy itself can lead to inflammation of bone marrow of the mandible or maxilla. In this case, it is also necessary to visit the stomatology department, and the maxillofacial surgeon will help to confirm whether there is inflammation of bone marrow. If there is corresponding inflammation of bone marrow, the maxillofacial surgeon is needed to determine whether surgical intervention is needed based on the application of antibacterial drugs; 3. Drug-related osteomyelitis: whether the patient has a history of applying drugs such as bisphosphonates, and if there is a history of application of these drugs, after tooth extraction A localized swelling of one side of the cheek appears, and attention should also be paid to whether there is drug-related osteomyelitis. This condition also requires a visit to the Department of Oral and Maxillofacial Surgery for surgical intervention and treatment on top of antimicrobial medication.