Do's and Don'ts After Orthognathic Surgery | Seoul Guide Medical The V-line surgery freely adjusts the length of the chin tip to create a small face. For a short chin and a wide face, the length and location of the chin are adjusted for a slimmer face with a V-line. For a long chin and a flat face, the front chin is shortened and the jaw bone under the ear is cut to create a smaller face. Additional information: -You must fast (no water or food) for at least 8 hours before surgery -You must info