Warshawsky H
Department of Anatomy, McGill University, Montreal, Quebec, Canada.
Anat Rec. 1989 Jun;224(2):242-62. doi: 10.1002/ar.1092240214.
It has been variously suggested that the organic matrix associated with the mineral phase of enamel is present as either calcified fibrils, central dark lines, peripheral sheaths around hexagonal crystals, or organic ghosts apparently contained within crystal profiles. The most consistent findings confirm the crystal ghost conception. Grid decalcification of nearly mature sectioned enamel and staining revealed hollow, noncrystalline structures whose external measurements were statistically identical to those of the dissolved crystallites, but with internal measurements too small to accommodate the crystallites. To explain these apparent ghosts in view of the incompatibility of ghosts with crystal structure, it has been proposed that the crystallites are not hexagonal in cross-sections and the hexagonal appearance is due to projections of parallelepiped-shaped crystallite segments with cut surfaces that are rhomboidal in shape. Material on the surface of such profiles would project as if it were contained within the profile. Hexagonal forms could not be demonstrated in isolated crystallites examined by transmission electron microscopy, high-resolution scanning electron microscopy, and replicas made of the isolated crystallite preparations examined by transmission electron microscopy. Existing evidence does not rule out the possibility that the noncrystalline profiles represent stain drawn into the holes left by the dissolved crystallites as a result of high capillarity forces.
关于与牙釉质矿相相关的有机基质，有多种不同的说法，它可能以钙化纤维、中央暗线、六方晶体周围的外周鞘或明显包含在晶体轮廓内的有机幽灵的形式存在。最一致的发现证实了晶体幽灵的概念。对几乎成熟的切片牙釉质进行网格脱钙和染色后，发现了中空的非晶态结构，其外部尺寸在统计学上与溶解的微晶相同，但内部尺寸太小，无法容纳微晶。鉴于幽灵与晶体结构不相容，为了解释这些明显的幽灵，有人提出微晶在横截面上不是六边形的，六边形外观是由于平行六面体形状的微晶片段的投影造成的，其切割面呈菱形。这种轮廓表面的物质会呈现出好像包含在轮廓内的样子。在通过透射电子显微镜、高分辨率扫描电子显微镜以及对透射电子显微镜检查的分离微晶制剂制作的复制品中，均未在分离的微晶中发现六边形形态。现有证据并不排除非晶态轮廓代表由于高毛细作用力而被吸入溶解微晶留下的孔洞中的污渍的可能性。
