Objectives: Patients with skeletal open-bite and skeletal deep-bite faces pre-surgically show varying amounts of relapse after orthognathic surgery. Among other factors, this relapse has been associated with the morphology of the face and the type of surgical technique. The hypothesis was tested that post-surgical vertical skeletal, dental and soft tissue changes after treatment were more determined by original facial type than by surgical technique. Methods: A sample of 54 adult patients with skeletal mandibular retrognathism treated with combined orthodontics and surgery was divided in three equal groups according to the pre-surgical mandibular plane angle PP-MPL: a low-angle group, normal-angle group and a high-angle group. The effects of the surgical treatment procedure by either only a mandibular advancement (BSSO), or only a le Fort I intrusion osteotomy or bimaxillary osteotomy were evaluated cephalometrically. Of each patient lateral headplates taken before orthodontics, before surgery, one day after surgery, one week after surgery, one month after surgery and about 5 years post-operatively were digitized. In this way the vertical skeletal, dental and soft-tissue changes relative to Sella-Nasion-line could be analyzed. Results: The gender, the type of fixation or an additional performed genioplasty did not have any influence on the vertical stability of the surgical procedures. The posterior facial height represented by Sella-Gonion decreased post-surgically in spite of the facial type and operation techniques. Patients treated with a Le Fort I osteotomy with or without BSSO exhibited better vertical skeletal stability than those treated with only a BSSO. Long-term dento-alveolar changes were not in accordance with skeletal changes. Soft-tissue response to orthognathic surgery was unpredictable and showed large individual variations. Conclusion: In orthognathic surgical cases the post-surgical vertical skeletal, dental and soft-tissue changes are not determined by facial type, but by surgical technique.

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