| 摘要 |
1470771 Dental moulding TECHNICAL DENTAL DEVELOPMENTS (LONDON) Ltd 4 June 1974 [4 June 1973] 26597/73 Heading B5A [Also in Division A5] The method of moulding suitable for making a model of a cut tooth on which a crown is to be mounted, as described in Specification 1,302,023, is modified in that the liquid polyester resin is filled with balls of a material, other than metal, which is inert to the polyester resin and has a higher specific gravity than said resin, materials such as glass, a silicate or silicon carbides being suitable. The liquid resin also contains an inert filler, such as quartz or calcium filler, so that the casting material is in the form of a paste. The size of the balls is such that they pass through a screen having a mesh size in the range from 120 to 300 perforations per inch, the balls being of equal size. |
