1, rinse your mouth with compound borax solution three days before operation, and clean your mouth if necessary. If an external incision is made, it is necessary to wash the scalp with 1: 1000 bromogeramine foam;

2. Routine frontal and lateral photos of the face are taken for postoperative comparison and curative effect evaluation, and three-dimensional skull ct can be done if conditions permit. X-ray film of maxilla was taken to understand the development degree of maxillary sinus. It can also make a three-dimensional skull model and accurately measure the amount of bone that needs to be removed from the cheekbones.

3. No source of oral infection, such as dental caries, periodontitis, oral ulcers, etc.;

4, good health, no organic diseases of important organs, no heart disease, hepatitis, nephritis, pneumonia and other diseases;

5. Women should avoid menstrual period during operation;

6. Preoperative blood routine and urine routine examination, routine health examination such as chest X-ray and electrocardiogram.