Abstract: Inorganic material resisting to high temperatures for installations intended to form structural glass elements which, owing to the precision and the quality of the forming surface, do not require after forming any other surface treatment. The material is comprised of at least one forming surface based on at least one from the groups of a metal oxide a double metal oxide, and a crystalline solid solution. It has a monocrystalline structure. Preferred materials are Al.sub.2 O.sub.3, Cr.sub.2 O.sub.3, MgAl.sub.2 O.sub.4 and/or ZrO.sub.2.

Abstract: Composite materials for prosthesis purposes are indicated, which consist of a plastics matrix and an inorganic radiopaque filler which, as the essential components, contains a combination of compounds of the elements Gd, Sr and, if appropriate, La. The proportion of filler in the total composite material is between 20 and 90% by weight.The filler particles are in a silanized form of glass and/or glass ceramics and/or a sintered product and/or in the form of a mixture of their starting components and comprise (in % by weight): 1-31 of Gd.sub.2 O.sub.3, 7-32 of SrO, 0-18 of La.sub.2 O.sub.3, 14-62 of SiO.sub.2, 0-30 of B.sub.2 O.sub.3, 1-33 of Al.sub.2 O.sub.3 and 0-16 of Na.sub.2. A partial replacement of one or more of the radiopacity-causing compounds (Gd.sub.2 O.sub.3 SrO, La.sub.2 O.sub.3) by oxides of the elements Ca, Mg, Y, Zr, Ti, Ta and/or Nb is possible.

Abstract: An auditory ossicle prosthesis is described comprising a plate (1) with a groove (7) applied to its upper side and a shaft (2) eccentrically applied to its lower side. The prosthesis consists of a bioactive material and contains additionally at least in one partial area an insoluble bioinert material, which is applied mainly as a coating material in the form of an additive layer (S(+)) or a subtractive layer (S(-)). Suitable coating processes and substances are disclosed. If S(-) layers are applied, they may be exposed subsequently to a sealing and/or silanizing treatment.

Abstract: Prosthesis for the partial or complete reconstruction of the rear auditory canal wall, with a hollow cylindrical sleeve shape (1), not closed, and having at least in its two base areas (9) and (10) differential expansions in the manner of a hyperboloid with a preferentially elliptic cross section. A bioactive substance is used as the material. The inner wall of the prosthesis has a positive or negative (spatial) coordinate grid (6, 7). Selected partial surface areas (11, 12; 4) may be provided with an insoluble, bio-inert protective layer. The latter may consist of an additive protective layer (S(+)) or a substractive protective layer (S(-)). Appropriate coating processes are cited for both of these variants. When S(-) layers are produced, these may be exposed to a subsequent sealing and/or silanizing treatment.