Many reports have paid attention to skeletal stability after orthognathic surgery, but only few focalize attention on patients with III class III malocclusion and open bite. In this article, long-term stability (2 yr) of the maxilla and the mandible after orthognathic surgery in 40 patients with class III malocclusion and anterior open bite is evaluated. The sample has been obtained from those 420 patients with class III malocclusion treated with Le Fort I osteotomy isolated (group A, 20 patients) or in association with bilateral sagittal split osteotomy (group B, 20 patients) from 1985 to 2003. On the basis of cephalometric analysis obtained in the immediate postoperative period and 2 years after surgery, in class III patients with anterior open bite treated with mono- or bimaxillary surgery and stabilization with rigid internal fixation, the maxilla was demonstrated to remain in the postsurgical position, whereas a moderate rate of mandibular relapse dependent on the amount of surgical alteration of the mandibular position was present.