Deposition Mechanism of Inorganic Material in Denture Plaque

1.义齿菌斑和牙石的观察利用透射电子显微镜和电子探针对牙菌斑和牙石的形成过程进行了观察，3天时义齿表面松散结合的微生物间隙中出现了电子致密物质，6小时后仍未观察到牙菌斑。患者义齿表面出现层状物质(LS)，矿化严重。这些结果表明，义齿菌斑促进了钙的积累，义齿结石的形成是由微生物基质、细胞膜和/或LS启动的。原子力显微镜(SPM-9500)在义齿表面观察中的应用新近推出的原子力显微镜可以使我们更清楚地立体地观察义齿表面粗糙度等微小的表面结构，并配备图像处理计算机。通过原子力显微镜和传统扫描电子显微镜对义齿表面的对比观察来评价其观察效果，使用新引入的原子力显微镜可以更准确地获得表面粗糙度的图像。因此，原子力显微镜是研究义齿表面沉积膜、牙菌斑、义齿结石等情况的有效手段。

1. Observation of denture plaque and denture calculusThe formation process of the denture plaque and calculus were studied by means of transmission electron microscopy and EPMA.Amorphous electron dense materials appeared in the spaces between the loosely bound microorganisms on the denture surface at 3days, although the denture plaque was not observed at 6 hours. The lamellated substance (LS) appeared on the surface of the denture from the patients, and the substance was heavily mineralized. The initial mineral crystals appeared along the plasma membrane of microorganisms, the intermicrobiol matrix, and the LS.These results suggested that the denture plaque facilitates the calcium accumulation and the formation of the denture calculus is initiated by the interminicrobiol matrix, the cell membrane, and/or the LS.2. Application of Atomic Force Microscope(SPM-9500) to observation of denture surfaceThe recently introduced atomic force microscope can enable us to three-dimensionally observe the minute surface structures of the denture like ruggedness more clearly, being equipped with an image processing computer. Its observation efficacy was evaluated through comparative observations of denture surfaces between an atomic force microscope and a traditional scanning electron microscope.More accurate images of surface ruggedness were more easily obtained by employing the newly introduced atomic force microscope. Therefore , it was concluded that the atomic force microscope is an effective device for research observation of the denture surface deposited with pellicle, denture plaque and denture calculus and so force.