Kim Myung-In, Kim Jun-Hwa, Jung Seunggon, Park Hong-Ju, Oh Hee-Kyun, Ryu Sun-Youl, Kook Min-Suk
Department of Oral and Maxillofacial Surgery, School of Dentistry, Dental Science Research Institute, Chonnam National University, 77, Yongbongro, Buk-Gu, Gwangju 500-757 South Korea.
Maxillofac Plast Reconstr Surg. 2015 Oct 16;37(1):36. doi: 10.1186/s40902-015-0036-y. eCollection 2015 Dec.
This study was performed to evaluate three-dimensional positional change of the condyle using three-dimensional computed tomography (3D-CT) following unilateral sagittal split ramus osteotomy (USSRO) in patients with mandibular prognathism.
This study examined two patients exhibiting skeletal class III malocclusion with facial asymmetry who underwent USSRO for a mandibular setback. 3D-CT was performed before surgery, immediately after surgery, and 6 months postoperatively. After creating 3D-CT images by using the In-vivo 5™ program, the axial plane, coronal plane, and sagittal plane were configured. Three-dimensional positional changes from each plane to the condyle, axial condylar head axis angle (AHA), axial condylar head position (AHP), frontal condylar head axis angle (FHA), frontal condylar head position (FHP), sagittal condylar head axis angle (SHA), and sagittal condylar head position (SHP) of the two patients were measured before surgery, immediately after surgery, and 6 months postoperatively.
In the first patient, medial rotation of the operated condyle in AHA and anterior rotation in SHA were observed. There were no significant changes after surgery in AHP, FHP, and SHP after surgery. In the second patient, medial rotation of the operated condyle in AHA and lateral rotation of the operated condyle in FHA were observed. There were no significant changes in AHP, FHP, and SHP postoperatively. This indicates that in USSRO, postoperative movement of the condylar head is insignificant; however, medial rotation of the condylar head is possible. Although three-dimensional changes were observed, these were not clinically significant.
The results of this study suggest that although three-dimensional changes in condylar head position are observed in patients post SSRO, there are no significant changes that would clinically affect the patient.
本研究旨在通过三维计算机断层扫描（3D-CT）评估下颌前突患者单侧矢状劈开下颌支截骨术（USSRO）后髁突的三维位置变化。
本研究检查了两名表现为骨骼Ⅲ类错牙合伴面部不对称的患者，他们接受了USSRO以进行下颌后缩。在手术前、手术后即刻和术后6个月进行3D-CT检查。使用In-vivo 5™程序创建3D-CT图像后，构建轴向平面、冠状平面和矢状平面。在手术前、手术后即刻和术后6个月测量两名患者从每个平面到髁突的三维位置变化、轴向髁突头轴角（AHA）、轴向髁突头位置（AHP）、额状髁突头轴角（FHA）、额状髁突头位置（FHP）、矢状髁突头轴角（SHA）和矢状髁突头位置（SHP）。
在第一名患者中，观察到手术侧髁突在AHA处向内旋转，在SHA处向前旋转。手术后AHP、FHP和SHP没有显著变化。在第二名患者中，观察到手术侧髁突在AHA处向内旋转，在FHA处向外旋转。术后AHP、FHP和SHP没有显著变化。这表明在USSRO中，髁突头的术后移动不明显；然而，髁突头向内旋转是可能的。尽管观察到了三维变化，但这些在临床上并不显著。
本研究结果表明，虽然在SSRO术后患者中观察到髁突头位置的三维变化，但没有会在临床上影响患者的显著变化。
