Arch coordination does not affect the stability in class III orthognathic surgery patients.

The purpose of this study was to evaluate if the arch coordination manifested by preorthodontics had an effect on the short-term stability after orthognathic surgery by evaluating the B point, menton, overjet, and overbite. The subjects were 10 healthy adult female and male Koreans (mean age, 24.9 years) with insufficient arch coordination and 10 healthy adult female and male Koreans (mean age, 22 years) with sufficient arch coordination. All subjects had sagittal split ramus osteotomy with 1-piece maxillary Le Fort I surgery with/without genioplasty done from the same practitioner at Kyung Hee University Hospital at Gangdong from 2009 to 2011. All arch widths of the maxilla and mandible were measured. Cephalometric tracings of the subjects were made of the presurgical and postsurgical period with a follow-up at 3 months. Relapse was measured according to cephalometric tracing changes using the V-ceph Cephalometric Analysis Software version 5.5(Osstem, Seoul, South Korea). Insufficient arch coordination did not definitively affect the overall treatment outcome. There was significant difference in the horizontal dimensions of the mandible (vertical plane to point B, overjet) in the study group. The study group showed instability in orthodontic factors, whereas skeletal factors were stable. Vertical dimensions (horizontal plane to point B, horizontal plane to menton, overbite) were not statistically significant.