Presurgical orthodontic treatment may be hampered by anomalous anatomic relations, function and dento-alveolar compensation. A stabilizing, solid postsurgical occlusion requires presurgical dento-alveolar decompensation. Some sagittal overcorrection simplifies postsurgical orthodontic treatment. In distorelations, a diastema created between maxillary lateral incisors and cuspids may be helpful in this respect. The diastema is providing space for overcorrection and consequently the postsurgical orthodontic treatment can be simplified. In mesiorelations, creating additional space is not required because premature frontal contact is not a disturbing factor. Conversely, in short face patients frontal contact is just useful for gaining facial height.