Iijima M, Tohda H, Suzuki H, Yanagisawa T, Moriwaki Y
Department of Dental Materials and Technology, School of Dentistry, Asahi University, Gifu, Japan.
Calcif Tissue Int. 1992 Apr;50(4):357-61. doi: 10.1007/BF00301634.
In order to study the effect of F- on tooth enamel-like apatite formation, crystal growth experiments were carried out in the presence of 0.1 approximately 2 ppm F- at 37 degrees C and at pH 6.5 in a model system of enamel formation where octacalcium phosphate (OCP) was stable. Morphology changed from long and thin ribbons to small needle-like plates, and the product changed from OCP to apatite with an increase in F- concentration. In the presence of 0.1-1 ppm F-, apatite-OCP intergrowth took place, and crystals composed of apatite and OCP lamellas were formed. These crystals showed long and thin plate-like morphology and embeded an OCP lamella in the center of the crystal. The OCP lamella and its (100) planes were parallel to the (100) planes of apatite. The thickness of OCP decreased and that of apatite increased with an increase in F- concentration. Some apatite crystals obtained at 1 ppm F- embedded a central plane instead of the distinct OCP lamella. The result indicates that initially formed, thin, plate-like OCP acted as a template for the subsequent epitaxial overgrowth of apatite and, moreover, F- played an important role in regulating the apatite-OCP intergrowth.
为了研究氟离子（F⁻）对牙釉质样磷灰石形成的影响，在模拟牙釉质形成体系中开展了晶体生长实验，该体系中磷酸八钙（OCP）稳定，实验温度为37℃，pH值为6.5，F⁻浓度在0.1至2 ppm之间。随着F⁻浓度增加，形态从细长条带变为小针状板，产物从OCP变为磷灰石。在0.1 - 1 ppm F⁻存在下，磷灰石 - OCP共生发生，形成了由磷灰石和OCP薄片组成的晶体。这些晶体呈细长板状形态，在晶体中心嵌入一个OCP薄片。OCP薄片及其（100）面与磷灰石的（100）面平行。随着F⁻浓度增加，OCP厚度减小，磷灰石厚度增加。在1 ppm F⁻下获得的一些磷灰石晶体嵌入的是一个中心平面而非明显的OCP薄片。结果表明，最初形成的薄片状OCP作为磷灰石后续外延生长的模板，此外，F⁻在调节磷灰石 - OCP共生中起重要作用。
