A method is provided for scanning the surface of an object in which moisture such as saliva or water is present on the surface. First and second sources of inhibitors are provided with the first source consisting of a powdered corrosion inhibitor consisting of sodium sebacate, potassium sebacate, dicyclohexylammonium nitrite, sodium nitrite, zinc gluconate, sodium gluconate, and calcium nitrite. As the detecting rotator rotates, a change occurs in magnetic lines of force from the magnet. The sliding tray is slidably mounted in the first guiding recess of the first base and has a sliding recess and a convex surface slidably mounted on and abutting against the first base in the first guiding recess. Generally, the anti-migration feature allows the artificial meniscus to be implanted into the patient’s knee and maintain its position within the knee without penetrating the adjacent bone. Depending on the gait mode, such as walking or running, one of the desired vertical positions is selected, or the desired vertical positions are combined by taking the weighted average thereof or the like, thereby determining a final desired vertical position.