Ueki Koichiro, Yoshizawa Kunio, Moroi Akinori, Iguchi Ran, Kosaka Akihiko, Ikawa Hiroumi, Saida Yuriko, Hotta Asami, Tsutsui Takamitsu
Department of Oral and Maxillofacial Surgery, Division of Medicine, Interdisciplinary Graduate School, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3893, Japan.
Department of Oral and Maxillofacial Surgery, Division of Medicine, Interdisciplinary Graduate School, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3893, Japan.
J Craniomaxillofac Surg. 2015 Sep;43(7):1208-17. doi: 10.1016/j.jcms.2015.05.007. Epub 2015 Jun 9.
The purpose of this study was to evaluate change in computed tomography (CT) value of condyle and temporomandibular joint (TMJ) disc position after sagittal split ramus osteotomy (SSRO) setback surgery, retrospectively.
The subjects were 76 patients (152 condyles) who underwent bilateral SSRO setback surgery. They were divided into 2 groups (43 symmetric patients and 33 asymmetric patients). CT values (pixel values) of 5 sites of the condyle and condylar width, length, horizontal angle were measured pre-operatively and 1 year post-operatively. Disc position was classified as anterior disc displacement, anterior type, fully covered type and posterior type, preoperatively and postoperatively using magnetic resonance imaging (MRI).
In maximum CT value at the center of the condyle, post-operative value was significantly lower than pre-operative value bilaterally (Deviation side: P = 0.0003, Non-deviation side: P = 0.0003) in asymmetry group. In minimum CT value at the center of the condyle, the post-operative value was significantly lower than the pre-operative value bilaterally (Deviation side: P = 0.0309, Non-deviation side: P = 0.0004) in the symmetry group. With regard to maximum CT value at the lateral site of the condyle in the deviation side, the value for the anterior disc displacement group was significantly larger than that of the posterior type pre-operatively (P = 0.0123). CT value of the anterior disc displacement group was significantly larger than those of some other areas pre- and post-operatively (P < 0.05).
This study suggested that CT value of condylar bone changes after 1 year in SSRO and anterior disc displacement may partially affect the CT value of the condyle in the TMJ in mandibular prognathism patients.
本研究旨在回顾性评估下颌升支矢状劈开截骨术（SSRO）后退手术后髁突的计算机断层扫描（CT）值变化以及颞下颌关节（TMJ）盘位置变化。
研究对象为76例行双侧SSRO后退手术的患者（152个髁突）。他们被分为两组（43例对称患者和33例不对称患者）。术前及术后1年测量髁突5个部位的CT值（像素值）以及髁突宽度、长度、水平角度。术前及术后使用磁共振成像（MRI）将盘位置分为盘前移位、前位型、完全覆盖型和后位型。
在不对称组中，双侧髁突中心的最大CT值术后显著低于术前（偏斜侧：P = 0.0003，非偏斜侧：P = 0.0003）。在对称组中，双侧髁突中心的最小CT值术后显著低于术前（偏斜侧：P = 0.0309，非偏斜侧：P = 0.0004）。关于偏斜侧髁突外侧部位的最大CT值，术前盘前移位组的值显著大于后位型组（P = 0.0123）。盘前移位组的CT值在术前和术后均显著大于其他一些区域（P < 0.05）。
本研究表明，SSRO术后1年髁突骨的CT值发生变化，并且盘前移位可能部分影响下颌前突患者颞下颌关节中髁突的CT值。
