Imaging analysis of temporomandibular joint anatomy changes after intraoral condylectomy combined with orthognathic surgery

目的 对口内入路髁突切除同期正颌术后的面部对称性及颞下颌关节结构变化定量研究,评价手术效果的稳定性.方法 收集10例经口内入路髁突切除同期正颌手术患者的随访资料,利用ProPlan软件对术后1周内(T1)、半年(T2)、1年以上(T3)的螺旋CT数据行三维重建、定点测量,测量项目包括面部对称性、髁突在三维方向的轴角、髁突-关节窝相对位置及髁突形态相关指标.采用一致性检验、重复测量资料的方差分析对结果进行统计学分析.结果 面部不对称畸形矫治术后的患侧下颌升支高度随时间呈缓慢降低趋势[T1、T2、T3分别为(67.81±6.95)、(64.49±6.24)、(63.05±7.07) mm](P＜0.05),同时颏点偏移程度减小[T1、T2、T3颏前点距正中矢状面的距离分别为(2.79±4.93)、(0.37±4.20)、(0.33±3.97) mm] (P＜0.05),术后各阶段(牙合)平面倾斜角度及下颌高度的不对称性比较,差异均无统计学意义(P＞0.05).术后髁突在三维空间的位置及形态变化趋势为双侧髁突水平位轴角逐渐变大患侧T1、T2、T3(分别为71.95°±7.47°、74.73°±8.44°、76.56°±5.22°;健侧分别为72.60°±5.56°、76.00°±5.30°、77.19°±6.20°)(P＜0.05).双侧髁突向上移动[T1、T2、T3患侧关节上间隙分别为(8.78±4.38)、(4.11±2.49)、(3.27±1.96) mm;健侧分别为(3.63±1.49)、(2.52±1.19)、(2.38±1.11)mm](P＜0.05),患侧髁突向内移动,但变化速度随时间推移逐渐趋缓,盘-突-窝的相对位置随时间延长趋于稳定;患侧髁突内外径逐渐缩小[T1、T2、T3分别为(14.98±2.39)、(14.04±2.68)、(13.74±2.89) mm](P＜0.05),表面凸起形成类似正常髁突的形态,健侧髁突表面形态也有改变,但二者差异均无统计学意义(P＞0.05).结论 口内入路髁突切除术结合相应的正颌外科术式能在治疗病变的同时,有效矫正髁突良性肿物或良性肥大患者的面部不对称畸形,术后面部对称性恢复良好并保持,术后半年髁突相对位置及髁突形态趋于稳定.Objective To quantitatively analyze the changes of facial symmetry and temporomandibular joint structure at different periods after intraoral condylectomy combined with orthognathic surgery,and to evaluate the long-term stability after the operation.Methods Spiral CT data of 10 cases treated by intraoral condylectomy combined with orthognathic surgery were collected,and then reconstructed by ProPlan software.Mark points were drawn on the 3D-images reconstructed immediately after the operation,and 6 months and 12 months after the operation.The measurements parameters included condylar axis angle in three dimensions,condylar-glenoid relative position and condylar facial morphology related indicators.The results were statistically analyzed by the consistency test and the variance of repeated measurement data.Results The facial asymmetry of the patients was corrected after operation,the height of the affected mandibular ascending ramus(T1:[67.81±6.95] mm,T2:[64.49±6.24] mm,T3:[63.05±7.07] mm) as well as the degree of pogonion deviation decreased(T1:[2.79±4.93] mm,T2:[0.37±4.20] mm,T3:[0.33 ± 3.97] mm) (P＜0.05).But the tilt angle of the occlusion plane and the degree of mandibular height asymmetry had no significant difference between all the post-operative periods(P＞0.05).The post-operative 3D changes of the position and shape of the resected and its contralateral condylar showed that the bilateralcondylar axis angle in the horizontal plane gradually grew after operation(affected condyle:71.95°±7.47°,74.73°±8.44°,76.56°±5.22°;control condyle:72.60°±5.56°,76.00°±5.30°,77.19°±6.20° and had significant difference between all the post-operative periods)(P＜0.05),the condyle moved slowly upward on both sides (superior space on the affected side:[8.78±4.38] mm,[4.11±2.49] mm,[3.27±1.96] mm;on the control side:[3.63t1.49] mm,[2.52±1.19] mm,[2.38±1.11] mm)(P＜0.05),and moved inward only on the affected side(P＜0.05).All the above changes slowed down over time,and the disc-condyle-fossa relative position tended to be stable over time as well.The condyle diameter on the inside-outside direction gradually decreased on the affected side(T1:[14.98±2.39] mm,T2:[14.04±2.68] mm,T3:[13.74±2.89] mm)(P＜0.05),and the surface morphology,of the resected condyle was similar to the normal side.There were also some condylar surface morphological changes on the control side,but no statistical significance was found between different periods after the peration(P＞0.05).Conclusions The intraoral condylectomy combined with orthognathic surgery can eliminate condylar lesions effectively and correct the facial asymmetry caused by condylar benign tumor and hyperplasia.The facial symmetry can be maintained well after the operation,and the post-operative condylar morphology changes tended to be stable six months after the operation.北京市科学技术委员会首都临床特色应用研究基金; The Capital Featured Clinical Application Research Project of Beijing Municipal Science & Technology CommissionPubMed中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)6350-3565