Dental and Oral Medical Centre, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
Department of Dentistry and Oral Surgery, Jyosuikai Imamura Hospital, Tosu, Saga, Japan.
Sci Rep. 2018 Feb 12;8(1):2858. doi: 10.1038/s41598-018-21291-3.
Previous investigators have reported that transplanted demineralised dentin matrix (DDM) influences bone formation in vivo. However, the specific mechanism of how dentinal tubules contribute to bone formation has not been determined with regard to DDM transplantation therapy. In this study, we ultrastructurally investigated how DDM contacted the surrounding newly formed bone using a scanning electron microscopy (SEM) three-dimensional reconstruction method that is based on focused ion beam slicing and SEM (FIB/SEM). A pulverised and processed DDM derived from human teeth was implanted into rat calvarial bone defects, and a series of X-ray computed tomographic images were obtained over 12 weeks. Implants with surrounding new bone were removed and histologically examined using FIB/SEM. After obtaining objective block-face images, the target boundary face was reconstructed three-dimensionally. The osteocytes of the new bone tissue surrounding the DDM formed a network connected by their cellular processes and formed bone tissue. It is also interesting that the cellular processes of the osteocytes extended into the dentinal tubules, and that bone tissue with canaliculi had formed and filled the DDM surface.
先前的研究人员已经报告说，移植的脱矿牙本质基质（DDM）会影响体内的骨形成。然而，关于 DDM 移植治疗，牙本质小管如何有助于骨形成的具体机制尚不清楚。在这项研究中，我们使用基于聚焦离子束切片和扫描电子显微镜（FIB/SEM）的扫描电子显微镜（SEM）三维重建方法，从超微结构上研究了 DDM 如何与周围新形成的骨接触。将源自人牙齿的粉碎和加工的 DDM 植入大鼠颅骨骨缺损中，并在 12 周内获得一系列 X 射线计算机断层扫描图像。取出带有周围新骨的植入物，并使用 FIB/SEM 进行组织学检查。获得目标块面图像后，对目标边界面进行三维重建。DDM 周围新骨组织中的成骨细胞通过细胞突起形成一个网络，并形成骨组织。有趣的是，成骨细胞的细胞突起延伸到牙本质小管中，并且已经形成并填充了 DDM 表面的有管腔的骨组织。
