Ectrodactyly jaw angle depends on the aesthetic proportions of the face. If the ectrodactyly is particularly dramatic, the surgery can cut off the entire protruding part of the jaw angle. In addition to shaving off the entire jaw angle, one can also consider cutting off the outer plate of the deep branch of the mandibular body for more dramatic results. This can be predicted and executed by simulation before surgery and a guide plate between surgeries to achieve a more accurate and symmetrical postoperative result. The surgical treatment can be more accurately informed preoperatively about the possible postoperative results by using a guide plate or doing a simulation before surgery. With the guide, accurate cuts can be made and postoperative bilateral symmetry will be more desirable. It is also possible to operate through the surgeon’s experience. For the average person, it is not obvious to the naked eye whether the bilateral symmetry or asymmetry is not distinguishable, probably due to inaccurate bony data from the preoperative simulation.