WORKPIECE FOR DENTURE MANUFACTURING Russian patent published in 2021 - IPC A61K6/17 A61K6/802 A61C13/08 A61C13/83 C04B35/111 C04B35/64 C04B38/00 C04B41/00 C04B41/48 C04B41/49 C04B41/52 C04B111/00 

FIELD: dentistry.

SUBSTANCE: group of inventions relates to a workpiece for the manufacture of a dental prosthesis, to a porous substrate and to a composite block based on such a workpiece, as well as to methods for the manufacture of the above-mentioned workpiece, substrate and composite block. The workpiece contains a group of agglomerated ceramic, glass-ceramic or glass particles, so that (in vol.%): more than 40% and less than 90% of the particles of the above group have a size of more than 0.5 microns and less than 3.5 microns (hereinafter referred to as "enamel particles") and more than 10% and less than 60% of the particles of the group have a size of more than 3.5 microns and less than 5.5 microns (hereinafter referred to as ‘dentin particles’). The particle size distribution of this group of particles is bimodal and contains the first and second main modes, with the first main mode being more than 1.5 microns and less than 3.5 microns, and the second mode being more than 3.5 microns and less than 5.5 microns. Particles of enamel and dentin together account for more than 90% of the volume of agglomerated particles. And the microstructure of the workpiece is such that there is an X axis, called the ‘axis of variation’, along which the ratio Ve / (Ve + Vd) continuously changes, where Ve and Vd denote the vol.% of enamel particles and dentin particles, respectively. The method for making a workpiece includes obtaining a suspension of the corresponding particles with the above bimodal particle size distribution; centrifugation of such a suspension, providing an acceleration of more than 50 g, and compaction with the formation of a workpiece. A porous substrate is obtained by sintering the above preform, a composite block is obtained by impregnating such a porous substrate with a resin.

EFFECT: group of inventions makes it possible to obtain a continuous and gradual change in the optical and mechanical properties of the composite block, which makes it possible to manufacture a denture, the appearance and mechanical properties of which are essentially identical to those for a natural tooth.

22 cl, 1 ex, 5 dwg