Gum cancer; Oral and maxillofacial malignant tumor; Gingival ulcer; The wound does not heal after tooth extraction; Quality; Loose teeth; Cancer is the most common malignant tumor in oral and maxillofacial region, and squamous cell carcinoma is the most common malignant tumor. In China, squamous cell carcinoma of oral and maxillofacial region mostly occurs between 40 and 60 years old, with more males than females, and is common in gingival cancer, tongue cancer, buccal cancer, palatal cancer and maxillary sinus cancer. Oral cancer is in the north of the Yangtze River, accounting for 1.45-5.6% of all malignant tumors, and in the south of the Yangtze River. In India, it accounts for more than 40% of all malignant tumors. According to the degree of pathological differentiation, squamous cell carcinoma can generally be divided into grade ⅲ: grade ⅰ has high degree of differentiation and low degree of malignancy; Grade ⅲ differentiation is poor and the degree of malignancy is high; Undifferentiated cancer is the most malignant, and the incidence rate in gingival cancer is higher in China. According to the statistics of Shanghai Second Medical University, the proportion of malignant tumors is the highest, and most of them are well-differentiated squamous cell carcinoma.