Parr J A, Young T, Dunn-Jena P, Garetto L P
Department of Physiology, Indiana University School of Medicine, Indianapolis 46202, USA.
Biomaterials. 1996 Oct;17(19):1921-6. doi: 10.1016/0142-9612(95)00007-0.
Section thickness has been shown to affect the histomorphometrical measurement of bone-implant contact when analysed under brightfield microscopy. This study investigated whether microradiography of the bone-implant interface eliminated the errors associated with thick section analysis. Seven implant containing sections were utilized. Microadiographs of the thick (approximately 100 microns) sections were taken and the sections were subsequently ground to thicknesses of 50 microns and 25 microns. Photomicrographs were taken of the microradiographs and of the sections at each thickness (100, 50 and 25 microns) under brightfield microscopy. The photomicrographs were analysed for direct bone-implant contact in the cortical passage region and along the total length of the implant. The effect of section thickness on multiple fluorochrome labelling in 10 rabbit femur specimens was also examined. Centre-to-centre interlabel distance was measured for each label pair at a thickness of 100 microns and then again after the sections were ground to 50 microns and 25 microns. The thick (100 microns) sections showed a significantly greater amount of bone-implant contact than either the thin sections or the microradiographs. There was no difference in direct bone-implant contact measured by microradiography or thin sections. However, the microradiographic analysis showed a much lower variability of the bone-implant contact than the sections evaluated under brightfield microscopy. In addition, they have the added benefit of providing information on bone mineral density. Centre-to-centre interlabel distance was not significantly different for any label pair owing to section thickness. Data from this study provides evidence that the use of microradiographs for histomorphometrical analysis of the bone-implant interface is superior to brightfield analysis of thin sections owing to the lower variability of microradiographical data and the ability to obtain bone mineral density measures. Additionally, given that interlabel distance was not significantly affected by section thickness, the use of 100 microns thick sections for analysis of fluorochrome labels in cortical bone is supported.
在明场显微镜下分析时，切片厚度已被证明会影响骨-种植体接触的组织形态计量学测量。本研究调查了骨-种植体界面的显微放射ography是否消除了与厚切片分析相关的误差。使用了七个含种植体的切片。对厚（约100微米）切片进行显微放射摄影，随后将切片研磨至50微米和25微米的厚度。在明场显微镜下，对每个厚度（100、50和25微米）的显微放射照片和切片拍摄显微照片。对皮质通道区域和种植体全长的显微照片进行直接骨-种植体接触分析。还检查了切片厚度对10个兔股骨标本中多种荧光染料标记的影响。在100微米厚度下测量每个标记对的中心到中心标记间距离，然后在切片研磨至50微米和25微米后再次测量。厚（100微米）切片显示出的骨-种植体接触量明显多于薄切片或显微放射照片。通过显微放射摄影或薄切片测量的直接骨-种植体接触没有差异。然而，显微放射摄影分析显示骨-种植体接触的变异性比在明场显微镜下评估的切片低得多。此外，它们还有提供骨矿物质密度信息的额外好处。由于切片厚度，任何标记对的中心到中心标记间距离没有显著差异。本研究的数据提供了证据，表明由于显微放射摄影数据的变异性较低以及能够获得骨矿物质密度测量值，使用显微放射照片对骨-种植体界面进行组织形态计量学分析优于对薄切片的明场分析。此外，鉴于标记间距离不受切片厚度的显著影响，支持使用100微米厚的切片分析皮质骨中的荧光染料标记。
