摘要 |
A dental cement contains uranium compounds, e.g. uranyl compounds and red colouring materials, e.g. gold oxide, chrome-alumina colours, copper aluminate and manganic oxide, which give the cement an appearance similar to natural teeth both in natural and artificial light. The cement may be made in the form of a doughy paste by powdering a fused ceramic and mixing the powder with the uranium compounds, the red colouring materials and an acid, e.g. phosphoric acid. The ceramic may contain silica, alumina, aluminium phosphate, aluminium fluoride, calcium fluoride and lithium oxide. Specification 497,021 is referred to. |