The histological study of hard pieces such as tendons and calcified lesions and tissues is a field that has been gaining increased attention owing to the rapid development of implantable prostheses, among other factors. In these studies, serial sectioning is utilized to detect areas of interest throughout the entire piece, as it enables the application of the appropriate light and electron microscopy techniques in these areas. We propose the “three-sectioning method” that subjects the pieces to three consecutive cycles of embedding and sectioning to localize and study the areas of interest, as an efficient technique for these histological studies. The pieces were first embedded in epoxy resin and then cut into thick sections (approximately 300 μm) for the first cycle. Next, areas of interest selected on these thick sections were re-embedded in epoxy resin to be sectioned again (second sectioning) to obtain a series of semithin sections (1–3 μm). These semithin sections are usually studied using the most relevant techniques for light microscopy. Smaller areas of interest are selected to be cut into ultrathin sections (60–90 nm) for transmission electron microscopy. If necessary, the selected areas of the semithin sections can be embedded again, and then cut into new ultrathin sections. The different kinds of sections we have described here may also be studied using scanning electron microscopy. This systematic method facilitates correlative microscopy from lower to higher magnifications along with the usage of a broad variety of histological techniques including electron microscopy.

由于植入式假体的迅速发展以及其他因素，对诸如肌腱，钙化病变和组织等坚硬碎片的组织学研究已经引起了越来越多的关注。在这些研究中，连续切片用于检测整个工件中的感兴趣区域，因为它可以在这些区域中应用适当的光学和电子显微镜技术。我们提出了一种“三段式方法”，作为对这些组织学研究的一种有效技术，该方法将这些切片进行三个连续的嵌入和切片循环以定位和研究感兴趣的区域。首先将这些块嵌入环氧树脂中，然后将其切成较厚的部分（约300μm）以进行第一个循环。下一个，将在这些较厚的部分上选择的感兴趣区域重新嵌入环氧树脂中，再次进行切片（第二次切片），以获得一系列的半薄切片（1-3微米）。通常使用最相关的光学显微镜技术研究这些半薄切片。选择较小的感兴趣区域以切成超薄切片（60–90 nm）以进行透射电子显微镜检查。如有必要，可以再次嵌入半薄部分的选定区域，然后切成新的超薄部分。我们在此描述的不同部分也可以使用扫描电子显微镜进行研究。这种系统的方法有助于从低到高的放大倍数进行相关显微镜检查，以及使用包括电子显微镜检查在内的各种组织学技术。