Effect of perioperative buccal fracture of the proximal segment on postoperative stability after sagittal split ramus osteotomy.
OBJECTIVE
Buccal fracture of the mandibular proximal bone segment during bilateral sagittal split ramus osteotomy (SSRO) reduces the postoperative stability. The primary aim of this study is to evaluate the effect of this type of fracture on bone healing and postoperative stability after mandibular setback surgery.


METHODS
Ten patients who experienced buccal fracture during SSRO for mandibular setback movement were evaluated. We measured the amount of bone generation on a computed tomography scan, using an image analysis program, and compared the buccal fracture side to the opposite side in each patient. To investigate the effect on postoperative stability, we measured the postoperative relapse in lateral cephalograms, immediately following and six months after the surgery. The control group consisted of ten randomly-selected patients having a similar amount of set-back without buccal fracture.


RESULTS
Less bone generation was observed on the buccal fracture side compared with the opposite side (P<0.05). However, there was no significant difference in anterior-posterior postoperative relapse between the group with buccal fracture and the control group. The increased mandibular plane angle and anterior facial height after the surgery in the group with buccal fracture manifested as a postoperative clockwise rotation of the mandible.


CONCLUSIONS
Bone generation was delayed compared to the opposite side. However, postoperative stability in the anterior-posterior direction could be maintained with rigid fixation.
Department of Oral and Maxillofacial Surgery, Seoul National Unversity Dental Hospital, School of Dentistry, Brain Korea Plus, Seoul National Unversity, Seoul, Korea.
Sang-Yoon
SY
Lee
Department of Oral and Maxillofacial Surgery, Seoul National Unversity Dental Hospital, School of Dentistry, Brain Korea Plus, Seoul National Unversity, Seoul, Korea. ; Dental Research Institute, Seoul National University, Seoul, Korea.
Hoon Joo
HJ
Yang
Department of Oral and Maxillofacial Surgery, Seoul National Unversity Dental Hospital, School of Dentistry, Brain Korea Plus, Seoul National Unversity, Seoul, Korea.
Jeong-Joon
JJ
Han
Department of Oral and Maxillofacial Surgery, Seoul National Unversity Dental Hospital, School of Dentistry, Brain Korea Plus, Seoul National Unversity, Seoul, Korea. ; Dental Research Institute, Seoul National University, Seoul, Korea.
Soon Jung
SJ
Hwang
Fracture healing; Mandibular fracture; Postoperative stability; Sagitta split ramus osteotomy