Okazaki M
Department of Dental Technology, Osaka University Faculty of Dentistry, Japan.
J Dent Res. 1993 Sep;72(9):1285-90. doi: 10.1177/00220345930720090501.
Carbonate-containing fluoridated apatites were synthesized with two different modes of fluoride incorporation: by supplying F-free solution initially, followed by a F-containing solution; and with the order of supply of these solutions reversed. Both of these heterogeneously synthesized fluoridated CO3 apatites showed typical apatitic x-ray diffraction patterns; and both had similar total fluoride contents (0.87 +/- 0.07 and 0.94 +/- 0.03 mmol/g, respectively), i.e., half of the maximum fluoride content of fluorapatite. However, they differed considerably in their crystallographic properties. The 300 reflection peaks of both apatites were split, and their patterns were slightly different. In the former, SEM observation revealed capsule-like crystals with a rounded hexagonal shape. However, the latter had many small crystals, similar to those of homogeneous CO3 apatite, adhering to the larger hexagonal crystals, which were also similar to homogeneous fluorCO3 apatite. Wavelength-dispersive spectroscopy attached to the SEM showed a higher fluoride intensity in the former spectrum than the latter. These results suggest that two different types of heterogeneous fluoridated CO3 apatites were formed, CO3 apatite covered with fluorCO3 apatite, and fluorCO3 apatite covered with CO3 apatite. The simple two-step supply system used in this study is helpful for the study of complicated heterogeneous formation of apatites.
一种是先提供无氟溶液，然后再提供含氟溶液；另一种是将这两种溶液的供应顺序颠倒。这两种非均相合成的氟化碳酸磷灰石都显示出典型的磷灰石X射线衍射图谱；并且两者的总氟含量相似（分别为0.87±0.07和0.94±0.03 mmol/g），即氟磷灰石最大氟含量的一半。然而，它们的晶体学性质有很大差异。两种磷灰石的300反射峰都发生了分裂，并且它们的图谱略有不同。在前者中，扫描电子显微镜观察显示为圆形六边形的胶囊状晶体。然而，后者有许多小晶体，类似于均相碳酸磷灰石的小晶体，附着在较大的六边形晶体上，这些较大的六边形晶体也类似于均相氟碳酸磷灰石。扫描电子显微镜附带的波长色散光谱显示，前者光谱中的氟强度高于后者。这些结果表明形成了两种不同类型的非均相氟化碳酸磷灰石，即被氟碳酸磷灰石覆盖的碳酸磷灰石和被碳酸磷灰石覆盖的氟碳酸磷灰石。本研究中使用的简单两步供应系统有助于研究磷灰石复杂的非均相形成过程。
