Introduction - Asymmetries, Vertical and Horizontal Rotation, Mandibular Flaring - Surgical Techniques

No face is absolutely symmetrical. Therefore, because of the dentition conditions in the upper jaw and the result of the orthodontic pretreatment, the sagittal forward or backward displacement of the lower jaw always includes a rotational component. Vertical growth differences in the area of the mandibular corpus must be taken into account. Rotation of the distal mandibular segment can lead to unfavorable positional changes of the proximal segment. Three-dimensional complexities can be predicted well using three-dimensional planning tools. If necessary, the surgical technique must be adapted and supplemented by additional procedures to obtain a functionally and esthetically satisfactory result. The frequency of facial asymmetries is high because a complete symmetry of the right and left half of the face can rarely be found. A distinction is made between structural and physiological asymmetries and genetically determined or acquired asymmetries (trauma). The cause of an asymmetry of the jaws can be in the upper or lower jaw, in both jaws, or also in the area of the skull base. In addition to a bony cause, changes in the number of teeth, tooth loss, and other dental causes could also be possible. In addition to asymmetries that are skeletal or dental in origin, there are a variety of asymmetries that can be caused by volume differences in the surrounding soft tissues or even by space-consuming processes.