Surgery is necessary when the maxillary cyst reaches 5 centimeters. 1. When maxillary sinus cyst increases to 5 centimeters, it will cause symptoms such as nasal discharge, nasal congestion and pain in the nasal area, and it may also trigger recurrent sinusitis, which seriously affects the patient’s normal life, so the patient’s maxillary sinus cyst must be operated when it reaches 5 centimeters. Surgical treatments include open decompression surgery, curettage and partial maxillectomy, etc. Follow the doctor’s advice. 2. A maxillary cyst is a fluid-containing cystic lesion in the maxilla that slowly increases in size, gradually causing expansion of the jaw and internal compression and resorption. Most maxillary cysts are caused by abnormalities in tooth development and eruption, and can be caused by dental infections and jaw injuries. It is recommended that if patients are found to have maxillary cysts, they should be treated under the guidance of a doctor in a timely manner, so as not to delay the treatment time and to avoid sequelae such as facial deformity, tooth loss and dysfunction.