Department of Pathology and Laboratory Medicine, American University of Beirut, Lebanon.
J Biol Regul Homeost Agents. 2013 Jan-Mar;27(1):177-87.
Distraction osteogenesis of the jaw is a common surgical practice in the treatment of pediatric craniofacial deformities. Autologous platelet rich plasma (PRP) has been used to increase the healing potential of bones in humans during distraction osteogenesis. This article aims to study the morphometric and morphologic parameters resulting from the effect of PRP on bone healing after mandibular distraction in rabbits. Right mandibular distraction was performed in 12 rabbits divided equally into 2 groups. PRP and physiological saline were injected, according to a defined protocol, in the callus following distraction of the experimental and control groups respectively. The rabbits were sacrificed after a consolidation period of 45 days and the mandibles were surgically removed. Bone mineral density, radiographic analysis, mechanical properties and histological features of the lengthened bones were assessed using radiographic examination, dual X-ray absorptiometry, biomechanical testing and histology. Results showed that the regenerate bone density, the amount of trabeculation in addition to the bone mineral density and mineral content, as measured by absorptiometry, were better with PRP but not significantly different between groups. Two radiographs revealed a more consistent healing in the experimental mandibles compared with erratic outcomes in corresponding controls. Two of the latter could not be subjected to any mechanical testing because the mandibular parts, connected with fibrous tissue, were separated. Consequently, the biomechanical test depicted greater maximal loads in the experimental group. The histological studies exhibited more ossification and less connective tissue fibers in the experimental group. PRP accelerated healing of mandibles in rabbits following distraction and improved their biomechanical properties. These findings have significant clinical implications on reducing the period of consolidation of the mandibles which may not be immobilized like other bones for long periods of time.
下颌骨牵张成骨术是治疗小儿颅面畸形的一种常见手术方法。富血小板血浆（PRP）已被用于增加人类在牵张成骨过程中骨骼的愈合潜力。本文旨在研究 PRP 对兔下颌骨牵张后骨愈合的形态和形态学参数的影响。将 12 只兔子的右侧下颌骨分为两组进行牵张，根据既定方案分别向实验组和对照组的骨痂中注射 PRP 和生理盐水。在 45 天的愈合期后，处死兔子并取出下颌骨。通过放射学检查、双能 X 线吸收法、生物力学测试和组织学评估，对延长骨的骨矿物质密度、放射学分析、机械性能和组织学特征进行评估。结果表明，PRP 组再生骨密度、骨小梁数量以及通过吸收法测量的骨矿物质密度和矿物质含量均优于对照组，但两组间无显著差异。两张 X 光片显示，实验组下颌骨的愈合情况更为一致，而对照组的结果则不一致。其中两个对照组的下颌骨因为与纤维组织相连而无法进行任何机械测试。因此，实验组的生物力学测试显示出更大的最大载荷。组织学研究显示，实验组的骨化程度更高，结缔组织纤维更少。PRP 加速了兔下颌骨牵张后的愈合，并改善了其生物力学性能。这些发现对减少下颌骨的愈合期具有重要的临床意义，因为与其他骨骼不同，下颌骨不能长时间固定。
