【作者】 马宏； 李玉晶；

【Author】 MA Hong,LI Yu-jing.(College of Stomatology, Capital University of Medical Sciences. Beijing 100050,China)

【机构】 首都医科大学口腔医学院；

【摘要】 目的:比较育龋窝沟菌斑和无龋窝沟菌斑的结构。方法:首先将拔除的前磨牙或磨牙进行双固定,颊舌向连续切两张牙片,再次锇酸固定后,1张牙片做显微放射照相分析,确定有龋和无龋牙各5颗,另一张牙片用环氧树脂包埋;部分磨除表层的环氧树脂以暴露牙本质和釉质,10％EDTA脱钙,将釉质完全溶解,将菌斑用环氧树脂包埋,超薄切片,做透射电镜观察。结果:有龋窝沟菌斑和无龋窝沟菌斑的结构有明显的区别:有龋窝沟菌斑中细胞成分较多,基质较少,细胞形态变化较多,多数细胞形态完整、包膜清晰,在基质中可见大量的膜样结构;无龋窝沟菌斑中细胞成分较少,基质成分较多,细胞之间可见明显的基质间隔,细胞形态变化较少,多为圆形。两者也有相同的特点:菌斑与釉质界面上有连续的电子密度的条带,未见明显的细胞分裂,无龋窝沟菌斑在整个菌斑的不同区域均可见到细胞壁的增厚、细胞内钙化、细胞内空泡变性等现象,并且明显多于有龋窝沟菌斑。结论:有龋窝沟菌斑和无龋窝沟菌斑的结构有显著的差别,前者的细菌代谢活力强于后者。更多还原

【Abstract】 OBJECTIVE: To study the structure of permanent molar fissure plaque. METHODS:The extracted tooth was immediately fixed with special fixing liquid for 24hr and then fixed in 2% osmic acid for 2 hrs. Buccolingual sections were made and then postfixed once again in 2% osmic acid for 1hrs. Embedding, grinding the sections. Decalcification to remove the fissure enamel in 10% EDTA the plaque was embedded once again. The ultrathin sections were made and the plaque was observed under transmission electron microscope. RESULTS: The structure of plaque in caries fissure was different to that in non-caries fissure. The plaque in caries fissure had more cells, less matrix, more kinds of cell shape than the plaque in non-caries fissure, and a membrane-like structure. There were same structural characters between plaques in caries fissure and in non-caries fissure, such as a continue electron dense band, intercellular and intracellular calcification, thicker cell membrane, intracellular vesicles and without cell divisions. CONCLUSION: Structure differences between plaques in caries and non-caries fissure suggested that the plaque in caries fissure was more cariogenic than plaque in non-caries fissure.更多还原