1. A method comprising: displaying one or more interactive two-dimensional images, each two-dimensional image representing at least bony tissue cranio-facial features of a patient and each two-dimensional image having one or more portions each associated with a corresponding portion of the patient's bony tissue such that a user may, via a user input device, cause movement of at least one of the one or more portions of such two-dimensional image to simulate movement of the corresponding portion of the patient's bony tissue in an osteotomy procedure; displaying a three-dimensional image representing exterior soft-tissue cranio-facial features of the patient; receiving input from a user regarding movement of a particular portion of the one or more portions of the two-dimensional image; and redrawing the three-dimensional image based at least on the movement of the particular portion of the two-dimensional image to simulate response of the exterior soft-tissue cranio-facial features of the patient to movement of a portion of the patient's bony tissue corresponding to the particular portion of the two-dimensional image.