Related Experiment Video
Updated: Mar 28, 2026
A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
Published on: January 28, 2020
The three-dimensional assessment of dynamic changes of the proximal segments after intraoral vertical ramus osteotomy
Seigo Ohba1, Noriko Nakao, Kousuke Awara
1Department of Regenerative Oral Surgery, Nagasaki University Graduate School of Biomedical Sciences , Japan.
Objectives:
The aim of this study was to assess the positional changes of the proximal segments after intraoral vertical ramus osteotomy (IVRO).
Method:
Fifteen patients underwent IVRO and were followed according to the authors' unique postoperative management regimen. The analyses of the positions and angles of the proximal segments were performed on frontal and lateral cephalograms, which were taken before surgery (T1) and within 3 days (T2), at 4 weeks (T3), and later than 6 months after surgery (T4). The three-dimensional positions of the condylar heads were also assessed by CT images, which were taken before and 1 year after surgery.
Results:
The proximal segments temporarily swung posteriorly and laterally with a center on the condylar head as a fulcrum point at T2 and T3, compared with T1, and they repositioned at T4. The condylar heads moved inferior approximately 2 mm with lateral rotation one year after surgery, as seen in the CT.
Discussion:
The condylar heads changed their positions physiologically for newly established jaw movement after IVRO with the authors' post-operative management regimen because the post-operative skeletal stability and the jaw function were good and stable using this method.
