After the doctor has marked the face and local anesthesia, the tear trough filler can officially begin. Usually, the needle is inserted on the lateral side of the tear trough, and the smooth threads are placed in the dermis/subcutaneous, while the spiral threads are placed in the subcutaneous/inferior orbital rim of the periosteum superficially, so that the threads will not be visible on the surface of the skin. The direction of the threads is fan-shaped, covering the tear trough and its surrounding tissues. The number of buried threads varies from person to person, usually 4-6 threads are buried on each side of the tear trough. If any threads are exposed to the skin after surgery, they can be cut directly. If the position of the buried threads is unsatisfactory, the smooth threads can be removed directly, while the spiral threads can only be removed by the surgeon because of excessive resistance. Therefore, in order to ensure the effectiveness and safety of buried thread surgery, please make sure the following points: buried thread surgery should be carried out in a regular medical institution, a regular operation place, by a professional surgeon, applying legal thread products, and through a standardized operation process.