Prosthesis (i.e. – artificial body members) – parts thereof – or ai – Ear or nose prosthesis
Patent
1982-12-29
1986-08-26
Apley, Richard J.
Prosthesis (i.e., artificial body members), parts thereof, or ai
Ear or nose prosthesis
128 92C, A61F 218
Patent
active
046080511
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The invention concerns a prosthesis for the total or partial replacement of the rear auditory canal wall together with a process for producing same.
Due to pathological conditions, it may be necessary to replace a part of the rear auditory canal wall, or even the entire rear auditory canal tract, by a permanent implant.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a prosthesis form similar to the actual anatomical conditions, to select an optimum material for the prosthesis, and to provide on the prosthesis means for the anatomically and geometrically accurate alignment and positioning of the prosthesis at the location of the implantation. It is a further object of the invention to design the partial areas of the surface of the prosthesis not intended for actual bonding with the bone (fusing zone: an implant/osseous hard tissue), so that they will be biochemically entirely resistant and bioinactive. Another object is to provide a process for the subsequent bioinactivation of selected partial areas of prostheses or parts of prostheses which are bioactive.
The object of the invention is attained with a prosthesis of the aforementioned type according to the invention in that the prosthesis is in the form of an open hollow cylindrical sleeve having a cut-out selection and having hyperboloid-shaped differential expansions at least in its two base areas wherein the expansions preferrably have elliptical cross sections and wherein the prosthesis comprises bioactive material. According to a particular embodiment, the inner wall is provided with a spatial coordinate grid. The grid may consist of two families of lines crossing each other, with one of the families comprising a plurality of hyperbolic lines extending essentially in the direction of the axis of the sleeve and the other of a plurality of elliptic lines extending essentially perpendicularly to the axis of the sleeve. The lines of the coordinate grid may be in the form of groove-like depressions of any cross-sectional shape, for example, triangular, rectangular, rounded, etc. It is also possible to provide the lines of the coordinate grid in the form of bead-like projections. According to a further form of embodiment of the invention, in place of continuous lines, discontinuous, periodically, arranged grid elements, for example, small pits or knobs, may be provided. It is advantageous in this case to produce the positive embodiments of the grid from the material of the prosthesis itself. The mean mesh width of the coordinate grid is between 1 and 2 mm. Advantageously, the length of the sleeve's cut-out section is greater than its means circumferential distance, and the shortest of all of the principal axes of internal ellipses produced by sections perpendicular to the axis of the sleeve is longer than the mean circumferential distance of the sleeve's cut-out section. Dimensioning may be effected so that the length of the sleeve continuously increases toward the two cuts where the sleeve's cut-out section has been cut and reaches a maximum there, while its minimum is attained at the sleeve area opposite the cut-out section. According to a particular embodiment, of the present invention, the wall thickness of the sleeve is between 0.5 and 2.0 mm, the average length of the sleeve between 12 and 25 mm, the mean circumferential distance of the sleeve's cut-out section between 7 and 14 mm, the mean length of the principal axes of the ellipses between 10 and 17 mm, the mean length of the secondary axes between 5 and 8 mm, and the positive or negative grid has a mean height or depth between 0.2 and 1.0 mm.
The bioactive material used preferably is a bio-glass ceramic. It is, however, also possible to use other bioactive materials, such as a bioactive composite or apatite-containing sinter products. Finally, it is also possible to make the prosthesis of the invnention of a core material with a coating of bioactive substances. According to a further embodiment of the invention, the auditory w
REFERENCES:
patent: 3922155 (1975-11-01), Bromer et al.
patent: 4135935 (1979-01-01), Pfeil et al.
patent: 4473909 (1984-10-01), Reck et al.
Broemer Heinz
Deutscher Klaus
Franek Henning
Reck Ralf
Apley Richard J.
Ernst Leitz Wetzlar GmbH
Isabella David J.
LandOfFree
Auditory canal wall prosthesis and process for producing same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Auditory canal wall prosthesis and process for producing same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Auditory canal wall prosthesis and process for producing same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2310349