Regeneration of periodontal ligaments in jawbone using materials driven by magnetic field

本研究的目的是在动态环境中利用纤维韧带构建硬组织的结缔组织结构。为了开发医疗器械，我们选择了元器件，并对齐了磁性材料对磁梯度的反应幅度和频率。我们使用了环氧树脂和磁性物质金属(钴铁氧体粉末)的混合材料。在皮下植入实验中，从组织病理和物理上证实了该材料的生物相容性。在静态和动态条件下观察了大鼠颅骨骨沟的愈合情况。在大鼠颅骨上形成宽约0.5、1.0和1.5 mm的硬脑膜沟。组织切片进行组织学观察。1.5 mm宽的沟与纤维结缔组织相连。用骨组织重建宽度为1.0 mm的骨沟。随后，在颅腔内血压的动态影响下，被1.0 mm宽的沟槽包围的离体骨没有显示骨性连接。在分离的骨表面和周围的骨表面，可以看到Sharpey纤维的一部分，它显示了嵌入钙化组织中的胶原纤维或束。结果表明，Sharpey纤维是由动力学效应形成的。为证实Sharpey纤维结构在颌骨牙槽内的形成，将烧结牙植入大鼠上颌骨第一磨牙槽内。取其他大鼠种植牙，1100℃烧结法灭菌。拔除第一磨牙。并很快将烧结牙植入拔除的牙窝内。用树脂将烧结牙与第二磨牙连接。植入后10d，烧结骨与牙槽骨之间可见肉芽组织和纤维结缔组织，轻度炎性细胞浸润。建议长期观察是必要的。

The aim of this study was to construct the connective structure of hard tissue by fibrous ligaments in dynamic environment. For the development of the medical appliance, we selected elemental components and aligned the amplitude and frequency of magnetic materials reacting to magnetic gradient. We used the mixture materials of epoxy resin and magnetic substance metals (cobalt ferrite powder). In experiment of subcutaneous implantation, the biocompatibility of this material was confirmed histopathologically and physically. The healing of bone groove in rat cranium was investigated in static and dynamic states. The grooves of about 0.5, 1.0, and 1.5 mm breadth through the dura mater were formed in rat cranium. Histological sections were histologically observed. The groove of 1.5 mm breadth was connected with fibrous connective tissue. The groove of 1.0 mm breadth was reconstructed by bone tissue. Subsequently, the isolated bone surrounded by groove of 1.0 mm breadth, which will come under the dynamic influence of blood pressure in cranial cavity, showed no bony connection. In a part, the Sharpey's fibers, which reveal collagen fibers or bundles embedded in calcified tissue, were seen on the isolated and the surrounding bone surfaces. It was suggested that the Sharpey's fibers were formed by dynamic effects. To confirm the formation of Sharpey's fiber structure in tooth socket of jawbone, sintered tooth was implanted in first molar tooth socket in rat maxilla. Implanted teeth were extracted from else rats, and sintered in 1100℃, and sterilized. First molar tooth was extracted. And soon sintered tooth was implanted in extracted tooth socket. Sintered tooth was connected to second molar with resin. Granulation and fibrous connective tissue with slight inflammatory cells infiltration was present between sintered bone and alveolar bone on 10 days after implantation. It was suggested that the long-term observation is necessary.