下颌前突患者下颌支矢状劈开截骨术后髁突运动轨迹的改变

Changes of the condyle movement traces after correction of mandibular protrusion by bilateral sagittal split ramus osteotomy

目的:研究双侧下颌支矢状劈开截骨术对下颌前突患者髁突运动轨迹的影响。方法:采用ARCUSdigma下颌三维运动轨迹描记仪,以髁突运动中心为参考点,研究30例正常受试者、14例下颌前突患者手术前后开口、前伸和左右侧向髁突运动的轨迹。用SPSSV11.0统计软件包进行配对t检验和成组t检验。结果:下颌前突患者术前、术后、正常组左侧髁突的运动轨迹与右侧基本相同,左侧髁突与右侧的开口、前伸和侧方运动范围无显著性差异(P>0.05)。术前组与正常组髁突运动轨迹差别较大,术前开口、前伸和侧方运动范围均小于正常组(P<0.05);术后与正常组髁突运动轨迹接近,术后开口、前伸和侧方运动范围与正常组无统计学差异;术前与术后组髁突运动轨迹差别较大,术前开口、前伸和侧方运动范围均显著小于术后组(P<0.05)。结论:下颌前突患者手术后,随着术后正畸治疗及咬合自我调整,建立了正常的咬合引导关系,使下颌功能运动趋向正常。

PURPOSE： To investigate the influences on the condyle movement traces after correction of mandibular protrusion by bilateral sagittal split ramus osteotomy. METHODS： With the ARCUSdigma 3-D mandibular kinesiograph and in 30 subjects with normal occlusion and 14 with mandibular protrusion, the condyle movements were recorded during mouth opening and closing, protrusion and lateral movements of the jaw. The condylar kinematic center was used as reference points. The average distance of the groups was compared using paired samples t test and group t test with SPSS V11.0 software package. RESULTS： The condyle movement traces before correction of mandibular protrusion by BSSRO were different from normal occlusion, but similar to normal occlusion after correction of mand!bular protrusion by BSSRO. During mouth opening, protrusion and lateral movements the condyle edge kinematic range in preoperative group was significantly smaller than that in the postoperative group and normal group （P〈0.05）. During lateral movements, the traces of both sides were asymmetrical. From lateral opening position back to ICP, the traces were in coincided, which showed occlusion interference and muscle functional restriction in lateral movement. In the 3-D directions, all of the protrusive movement bias of the condylar kinematic centered on both sides between the postoperative group and preoperative group （P〉0.05）, but not the normal occlusion group（P〈0.05）. In the 3-D directions, all of the lateral （left or right） movement bias of the condylar kinematic centered on both sides between the postoperative group and preoperative group（P〉0.05）, but not the normal occlusion group （P〈0.05）. CONCLUSION： In patients with mandibular prognathism, normal occlusion will be established with self regulation and postoperative orthodontics treatment, which lead to normal mandibular movement.