论文标题:兔下颌骨牵张成骨对肌间结缔组织及神经的影响
The Influences of Distraction Osteogenesis on Intramusucular Tissue and Nerves in Rabbits" Mandible
论文作者 李彦
论文导师 刘彦普；赵晋龙,论文学位 硕士,论文专业 口腔临床医学
论文单位 第四军医大学,点击次数 64,论文页数 60页File Size5687k
2005-04-01论文网 http://www.lw23.com/lunwen_12383892/ 牵张成骨;动物模型;肌束膜;Ⅰ、Ⅲ型胶原;转化生长因子
distraction osteogenesis; perimysium; collagen type Ⅰ、Ⅲ; inferior alveolar nerve; transforming growth factor
牵张成骨是依据张应力原理,以一定的频率和强度对保留血供的骨断端施以机械牵张力,从而诱导骨痂生长,延长骨骼,矫正骨畸形、修复骨缺损的一种新技术。具有不需另开辟骨供区,避免了二次手术,同时又能同步延长周围软组织的优点,自McCarthy将其引入颌面外科领域以来,在临床上得到了长足的应用。 本实验旨在建立兔下颌骨双侧牵张成骨动物模型,探讨不同牵张速率下兔下颌骨成骨过程中二腹肌肌束膜厚度和Ⅰ、Ⅲ型胶原比例及超微结构的变化以及牵张成骨造成的神经损伤修复过程中转化生长因子的表达情况,以寻求最佳的牵张方案,减少牵张成骨对周围软组织的不良影响,为临床应用提供一定的理论依据。 本实验依据常规牵张成骨的基本原理,利用改良的半埋置牵张器,在充分了解兔下颌骨解剖结构及下牙槽神经走向的基础上,采取骨皮质切开术,建立了兔下颌骨双侧同时牵张成骨动物模型,有效地延长了双侧下颌骨,组织化学染色显示成骨效果良好。实验证明该动物模型具有较高的可行性和可重复性,利用此模型进行研究牵张成骨机理及牵张对周围软组织的影响的实验是切实可行的。 在成功建立了牵张成骨动物模型的基础上,利用天狼猩红苦味酸-偏光镜等方法分析了不同牵张速率下不同时期肌束膜厚度
Distraction Osteogenesis (DO) is a new technique to reconstruct bone malformation or defects by inducing the development of callus then lengthening and widening the bone, by means of exerting mechanical force at certain rate to the bone which is cut but maintained blood supply. Because the DO technique do not need the supplying of bone, avoid second surgery and the soft tissues can be prolonged simultaneously, it has been used widely in clinic today since it has been imported into the field of oral and maxillofacial surgery by McCarthy firstly.. To study the optimal distracting procedure to decrease the side effect of distraction osteogenesis on soft tissue related for providing fundamental theory to clinic application, we established mandibular model of distraction osteogenesis bilaterally of rabbit, discussed the changes of the thickness , percentage of collagen type Ⅰ and Ⅲ and microstructure of the perimysium and observed the changes of transforming growth factor-beta (TGF-β) expression at various timeafter distraction at different distracting rate.According to the Law of Tension-Stress and being acquainted with the anatomic structure of the mandible and the course of inferior alveolar nerve, we established the model of distraction osteogenesis bilaterally in rabbits" mandible, advanced the mandible bilaterally effectively and studied the effect of osteogenesis of various time by histochemical method. It was proved that this kind model was stable and reliable and it was feasible to be used to study the principles and the influence on soft tissue related of distraction osteogenesis.Based on this model we studied the changes of the thickness of the perimysium, the acreage of cross section of the muscles , percentage of collagen type I and type III and the ratio of the acreage of cross section of the collagen and fascicles at different distracting rate by picrosirius-polarization and image analysis method. At the rate of lmm/d, the perimysium and the muscles were injured slightly, the percentage of collagen type III increased temporarily. At 4 week after distraction, the percentage of collagen type III decreased to normal level while the perimysium and the muscles became thickened slightly. The ratio of the acreage of cross section of the collagen and fascicles had not obvious changes. Nevertheless the perimysium was harmed severely , became thinner and the muscles atrophied at the rate of 2mm/d.. The percentage of collagen type III persisted a higher level. At the end of the experiment the acreage of cross section of the muscles had been recoverd but the perimysium became thicker than normal level and the ratio of the acreage of cross section of the collagen and fascicles increased. It was implied that there was the formation of excessive fibrous tissue of the intramuscular connective tissue which would produce bad influence on the function of the muscles. So it was appropriate for the perimysium to be distracted at the rate of 1mm/d.The samples of muscles for Scanning Electron Microscopy were made simultaneity to look into the changes of the microstructure anterior and posterior distraction osteogenesis. It showed that normally the collagen of the perimysium arranged orderly, compactly and undulately. But when the muscles were stretched longer the collagen became straighter and inclined to the long axis of the muscle. The perimysium was scathed slightly and its spatial arrangement was recovered eventually at the rate of 1mm/d. At the rate of 2mm/d, the perimysium not only lost its undulate arrangement, but also became loosen, even having lacuna some in part, and had not reverted ultimately at the end of this experiment. It implied that at upper distracting rate the perimysium was damaged badly and its spatial arrangement changed obviously. In a word it was fitting to distract at the rate of less than lmm/d.In this experiment we also observed the changes of transforming growth factor beta (TGF-p) expression in rabbits" inferior alveolar nerve (IAN) suffering distraction at different rate by histological immunhi
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