摘要
目的:分析山羊下颌骨牵张成骨中下颌骨牵张延长后髁突软骨表面的应力分布规律。方法:实验于2005-01/12在四川大学华西口腔医院动物手术中心和四川大学生物力学工程实验室完成。对1只山羊右下颌骨行骨皮质切开术后进行牵张,每日加力4次,牵张频率为每6小时0.2mm,每天共延长下颌骨0.8mm,牵张速率为0.8mm/d,连续加力12d后固定牵张器进入牵张固定期,牵张完成后第4周处死动物,采用SIMENSSOMATOM16型螺旋CT对其颅面骨行CT扫描后,将CT影像导入专用三维图像重建软件mimics进行三维模型的重建,并采用有限元分析软件Patran对所建下颌骨模型的颞下颌关节髁状突软骨表面的应力分布进行分析计算。结果:①术侧髁突软骨表面各部位的应力值远高于对侧犤术侧范氏力(MPa)/对侧范氏力(MPa):髁突前内斜面为14.6/0.92,髁突前中斜面为2.3/0.17,髁突前外斜面为4.5/0.9,髁突横嵴内1/3为5.7/0.6,髁突横嵴中1/3为2.6/0.8,髁突横嵴外1/3为1.8/0.11,髁突后内斜面为1.7/1.1,髁突后中斜面为0.9/0.2,髁突后外斜面为1.4/0.3犦。②术侧髁突前斜面为主要受压区域,髁突横嵴区和髁突后斜面为主要受拉区域。③术侧髁突前后向观察,髁突前斜面的范氏力平均值最大,髁突横嵴区域其次,髁突后斜面区域应力平均值最低;从髁突内外向观察,髁突内侧的平均范氏力大于髁突中份和外侧。结论:下颌骨牵张成骨中由于牵张力的作用会导致术侧髁突软骨表面产生一定的应力,应力的产生可能导致关节结构改变。
AIM： To analyze the stress distribution of the condylar cartilage during mandibular distraction osteogenesis in goats.
METHODS： The experiment was performed at the Key lab of Biomechanics, Sichuan University and Animal Operation Center, West China Stomatology Hospital ,Sichuan University from January to December 2005. Corticotomy was performed in right side mandible of 1 goat, distraction force exerting for 4 times daily, distraction frequency was 0.2 mm/ 6 hours, distraction rate was 0.8 mm/day, distraction period was 12 days, and then entering the consolidation period .The animal was sacrificed at 4^th week after distraction, CT scaning was done to the craniofacial bone with SIMENS SOMATOM 16 spiral CT, the 3D finite element model was established by the Mimics software, and then the stress distribution of the condylar cartilage was analyzed by Patran software.
RESULTS：①The value of Von Mises stress on the surface of the condylar cartilage of the distraction side was higher than that of the other side [Von Mises stress of distraction side / Von Mises stress of the other side： 14.6/0.92 in anterior-internal slope of condylar cartilage, 2.3/0.17 in anterior-middle slope of condylar cartilage,4.5/0.9 in anterior-external slope of condylar cartilage,5.7/0.6 in interal 1/3 of transverse ridge of condylar cartilage, 2.6/0.8 in middle 1/3 of transverse ridge of condylar cartilage, 1.8/0.11 in external 1/3 of transverse ridge of condylar cartilage, 1.7/1.1 in posterior-internal slope of condylar cartilage,0.9/0.2 in posterio-middle slope of condylar cartilage, 1.4/0.3 in posterior- external slope of condylar cartilage]; ②The anterior slope of condyle was the most pressed area, but the transverse ridge area and posterior slope area were most pulled area; ③In the observation of sagital direction, it showed that mean value of Von Mises stress on the surface of anterior slope was the maximum, followed by transverse ridge area and that was the minimal at posterior slope; In the observation of coronal direction, the mean value of Von Mises stress was larger in the internal area than the middle and external area. CONCLUSION： The distraction force will lead to some stress distribution on the surface of condylar cartilage during distraction osteogenesis, and the stress would make some changes in the TMJ （temporomandibular joint）.
出处
《中国临床康复》
CAS
CSCD
北大核心
2006年第37期103-106,共4页
Chinese Journal of Clinical Rehabilitation
基金
中国博士后科研基金资助(2003034420)
四川省应用基础研究计划资助(03JY029-088-1)~~
