Relapse and stability after mandibular setback surgery one year postoperatively: a retrospective study.
OBJECTIVE
A retrospective evaluation was performed of dentoalveolar and skeletal stability 1 year after mandibular setback surgery using intraoral vertical subcondylar osteotomy (IVSO) combined with intermaxillary fixation.


METHODS
Twenty-eight patients (16 men, 12 women) with skeletal Angle Class III malocclusions were included. Mean age at start of treatment was 23.9 years. All patients underwent combined surgical and orthodontic treatment. Dental casts and cephalometric measurements were performed for each patient before orthodontic treatment and at 8 weeks and 1 year after surgery.


RESULTS
Treatment changes from 8 weeks to 1 year after surgery were small but significant for the angular relationship between the maxilla and the mandible in the sagittal plane (ANB) (mean difference, -0.5 mm; P = .021), Wits appraisal (mean difference, -0.7 mm; P = .044), the inclination of the mandible in relation to the nasion-sella line (ML-NSL) (mean difference, -0.8 mm; P = .010), and the inclination of the lower incisors in relation to the nasion-point B line (Li-NB) (mean difference, -0.6 mm; P < .001). These findings for cephalometric values indicated a small skeletal relapse in sagittal and vertical relations. No significant dentoalveolar relapse occurred according to the dental cast evaluations.


CONCLUSIONS
The results clearly show that orthodontic treatment combined with IVSO provides a stable dental and skeletal result 1 year after treatment.
Consultant Orthodontist, Section for Orthodontics, Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
Eirik Torjuul
ET
Halvorsen
Consultant Orthodontist, Section for Orthodontics, Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
Ingri Yddal
IY
Beddari
Resident Orthodontist, Section for Orthodontics, Department of Clinical Dentistry, University of Bergen, Bergen, Norway. Electronic address: eer044@iko.uib.no.
Elisabeth
E
Schilbred Eriksen
Associate Professor, Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
Olav Egil
OE
Boe
Professor Emeritus, Section for Orthodontics, Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
Per Johan
PJ
Wisth
Associate Professor and Consulting Oral and Maxillofacial Surgeon, Department of Maxillofacial Surgery, Haukeland University Hospital, Bergen, Norway.
Sigbjorn
S
Loes
Consultant Oral and Maxillofacial Surgeon, Section for Oral and Maxillofacial Surgery, Department of Clinical Dentistry, University of Bergen, Bergen, Norway.
Ketil
K
Moen
D000293:Adolescent; D000328:Adult; D002508:Cephalometry / Q000379:methods; D003481:Cuspid / Q000473:pathology; D003724:Dental Arch / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D019248:Jaw Fixation Techniques; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery / Q000628:therapy; D008334:Mandible / Q000473:pathology; D008335:Mandibular Condyle / Q000601:surgery; D063168:Mandibular Osteotomy / Q000379:methods*; D008437:Maxilla / Q000473:pathology; D003765:Models, Dental; D008963:Molar / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D009967:Orthodontic Appliances; D009971:Orthodontics, Corrective / Q000379:methods; D057887:Overbite / Q000601:surgery / Q000628:therapy; D012008:Recurrence; D012189:Retrospective Studies; D012658:Sella Turcica / Q000473:pathology; D055815:Young Adult