Lee Seung-Woo, Jeong Bong-Jin, Jung Junho
Department of Oral & Maxillofacial Surgery, Kyung Hee University College of Dentistry, Kyung Hee University Medical Center, Seoul 02447, Republic of Korea.
Department of Dentistry, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea.
Life (Basel). 2025 May 23;15(6):845. doi: 10.3390/life15060845.
This study aimed to evaluate mandibular fixation techniques using monocortical plates following sagittal split ramus osteotomy in skeletal Class III patients. Ninety-three patients were categorized into three groups based on fixation methods: four-hole miniplate with one proximal and two distal screws (Group 1); four-hole miniplate with four screws (Group 2); sliding plate with two proximal and one distal screws (Group 3). Cone-beam computed tomography scans were obtained at three time points: immediately postoperative (T1), 6 months (T2), and 12 months (T3). The yaw, roll, and pitch rotations of the proximal segment, as well as horizontal and vertical changes of the pogonion, were evaluated. Group 1 exhibited significantly greater counterclockwise rotation of the proximal segments at T2 ( = 0.021) and T3 ( = 0.035) compared to the other groups. Additionally, Group 1 showed significantly smaller anterior and superior displacement of the pogonion at T3 (0.97 ± 2.10 mm, = 0.009; 0.03 ± 1.62 mm, = 0.011, respectively). Following surgical wafer removal, intimate occlusal contact is archived and the elimination of premature contacts through postoperative orthodontic treatment contributes to counterclockwise autorotation of the mandible. Therefore, anterior and superior movements of the pogonion are expected if firm fixation between the proximal and distal segments is achieved. Therefore, these findings suggest that a single proximal screw, as seen in a three-screw fixation, may act as a fulcrum, insufficiently resisting postoperative clockwise rotation of the distal segments.
本研究旨在评估骨骼Ⅲ类患者行下颌升支矢状劈开截骨术后使用单皮质板的下颌固定技术。93例患者根据固定方法分为三组：一枚近端螺钉和两枚远端螺钉的四孔微型钢板组（第1组）；四枚螺钉的四孔微型钢板组（第2组）；两枚近端螺钉和一枚远端螺钉的滑动钢板组（第3组）。在三个时间点进行锥形束计算机断层扫描：术后即刻（T1）、6个月（T2）和12个月（T3）。评估近端节段的偏航、滚动和俯仰旋转，以及颏点的水平和垂直变化。与其他组相比，第1组在T2（P = 0.021）和T3（P = 0.035）时近端节段逆时针旋转明显更大。此外，第1组在T3时颏点的前后向和向上位移明显更小（分别为0.97±2.10 mm，P = 0.009；0.03±1.62 mm，P = 0.011）。手术导板拆除后，实现了紧密的咬合接触，通过术后正畸治疗消除早接触有助于下颌逆时针自动旋转。因此，如果近端和远端节段之间实现牢固固定，预计颏点会有前后向和向上的移动。因此，这些发现表明，如三螺钉固定中所见的单个近端螺钉可能充当支点，不足以抵抗远端节段术后的顺时针旋转。
