METHOD FOR MAKING WORKPIECE FOR DENTAL RESTORATION, WORKPIECE AND DENTAL RESTORATION MADE FROM WORKPIECE Russian patent published in 2020 - IPC A61C13/00 

FIELD: medicine.

SUBSTANCE: group of inventions includes a method of making a workpiece from ceramic material, a pre-finished or sintered blank for use in dental restorations and dental restoration, relates to dentistry and is intended for making dentures from ceramic materials. Proposed method consists in the fact that first ceramic material and second ceramic material of different compositions are loaded into mould. At that said materials are compacted and subjected to sintering. Layer of first ceramic material is loaded in fluid state into mould, first open cavity is formed in layer. Second ceramic material is loaded in fluid state into first open cavity, and materials are pressed together and then subjected to heat treatment. Ceramic materials contain zirconium dioxide doped with yttrium oxide (Y₂O₃), wherein the first ceramic material differs from the material of the second ceramic material in colour and the ratio of stabilized crystalline forms available at room temperature. Dental restoration is monolithic and comprises at least one first layer located on cutter side from first ceramic material and second layer located on dentine side from second ceramic material. First layer has higher transparency and/or lower strength than the second layer. Ceramic materials contain zirconium dioxide doped with yttrium oxide (Y₂O₃), wherein the first ceramic material differs from the material of the second ceramic material in colour and the ratio of stabilized crystalline forms available at room temperature. Percentage of yttrium oxide in the second ceramic material is 4.5–7.0 % by weight, and in the first ceramic material is 7.0–9.5 % by weight, wherein the percentage content of yttrium oxide in the first ceramic material is higher than in the second ceramic material.

EFFECT: inventions widens the range of tools for the specified purpose.

27 cl, 6 dwg