| 摘要 |
<p>Dental cavities may be lined, prior to filling, with a paste comprising an aqueous phase containing Ca2+, PO4?3- and F-¿ and having a pH between 5 and 7 and, despersed therein, particles of hydroxy apatite, the surfaces of which have thereon a protective layer of calcium phosphate. The paste becomes unstable in the presence of the dentine of the tooth to deposit a hydroxy apatite layer on the dentine. The paste may be prepared by contacting hydroxy apatite particles with a saturated aqueous solution of calcium phosphate having a pH of between 4.6 and 8.5 whereby a calcium phosphate protective layer forms on the surface of the particles and removing any excess liquid, e.g. by decanting, to give a paste.</p> |
