Hello, the preparations for mandibular angle plastic surgery include: good health, no organic diseases of important organs, such as heart disease, hepatitis, nephritis, pneumonia and other diseases. No source of oral infection: such as dental caries, periodontitis, oral ulcer, etc. Female surgery should avoid menstrual period. Routine blood and urine tests, chest X-ray, electrocardiogram and other routine health checks should be done before operation, and special patients should also do X-ray examination of "serrated fracture of mandible" and lateral image of mandible. If you smoke, you should quit smoking before the operation. Aspirin, birth control pills and some anti-inflammatory drugs can cause increased bleeding, so these drugs should be stopped for a period of time before surgery. I hope my answer is helpful to you.