Postoperative condylar position by sagittal split ramus osteotomy with and without bone graft.
OBJECTIVE
The purpose of the present study was to determine how the condylar position is affected by the bone graft in the intersegmental space created by sagittal split ramus osteotomy.


METHODS
We compared the position of the condyle after sagittal split ramus osteotomy, without the bone graft (control group, n = 30) and with the bone graft (study group, n = 30) using computed tomography with a 2-mm thickness. Using 3-dimensional images and a 3-dimensional computer program, the pre- and postoperative displacement and rotation of the condyle in the axial (rotation and mediolateral movement of the condyle) and sagittal plane (anteroposterior and superoinferior movement of the condyle and rotation of the proximal segment) were measured. In addition, the relationship of the amount of rotation and backward movement of the mandible and the change in the condylar position was analyzed. For the statistical analysis, the t test (P = .05) and Wilcoxon rank sum test were used.


RESULTS
No statistically significant differences were found in any of the measurements of the 2 groups. Nevertheless, the mediolateral movement (P = .051) showed a relatively greater apparent difference, although the difference was not statistically significant. The condylar displacement had no relationship to the rotation of the mandible. However, the condylar displacement in relation to the amount of backward movement of the mandible was significant, especially when it was greater than 10 mm of setback.


CONCLUSIONS
Using a bone graft in the intersegmental gap of a sagittal split ramus osteotomy is considered an effective clinical method to secure the desirable intersegmental position because it helps to maintain the space with ease. Especially in cases with greater than 10-mm setback of the mandible, it prevents excessive condylar displacement.
Kang
Myoung Geun
MG
Department of Oral and Maxillofacial Surgery, Eulji General Hospital, Eulji University School of Medicine, Seoul, Korea.
Yun
Kyoung In
KI
Kim
Chang Hyun
CH
Park
Je-Uk
JU
D000293:Adolescent; D000328:Adult; D016025:Bone Transplantation / Q000502:physiology*; D005146:Facial Asymmetry / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000002:abnormalities / Q000601:surgery*; D008335:Mandibular Condyle / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000601:surgery; D010027:Osteotomy; D011378:Prognathism / Q000601:surgery*; D055502:Secondary Prevention; D018709:Statistics, Nonparametric; D013705:Temporomandibular Joint Disorders / Q000517:prevention & control; D014057:Tomography, X-Ray Computed; D055815:Young Adult