Long-term evaluation of patients with progressive condylar resorption following orthognathic surgery

The aim of this retrospective study was to evaluate the long-term treatment results of 26 patients who developed progressive condylar resorption (PCR) following a bilateral sagittal split advancement osteotomy (n=19) or a bimaxillary osteotomy (n=7). PCR was diagnosed clinically and from a comparison of pre- and postoperative cephalometric and orthopantomographic radiographs. The preoperative condylar configuration and resorption pattern were assessed distinguishing between 'deep bite' and 'open bite'. Patients with 'deep bites' tended to have more resorption on the superior site of the condyle, while 'anterior open bites' often had resorption on the superior and anterior sites of the condyle. The patients were divided into 2 groups, one receiving nonsurgical treatment that included splints, orthodontics with or without extractions and restorative dentistry. The second group underwent repeated surgery to treat skeletal relapse. Thirteen patients who underwent non-surgical treatment after orthognathic surgery had satisfactory results from orthodontic dental compensation, although only 3/13 had Class I occlusion. Another 13 patients had unacceptable occlusal and/or esthetic results and, therefore, underwent a second surgery. Following surgery, 7 patients had satisfactory occlusal and esthetic results and were skeletally stable. Four patients had 40-80% relapse, but with a stable occlusion. Two patients had 120% and 100% relapse, respectively and needed a third surgical intervention. The first patient had a stable occlusal and esthetic result with approximately 30% relapse at pogonion, but the second patient still had an unstable malocclusion with again 100% relapse. It appeared that, without surgical intervention after PCR, further resorption ceased after approximately two years. Second surgery appeared to produce variable results, but, in this series, the majority had significant improvement.