Patents by Inventor Lothar Völkl
Lothar Völkl has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20230249379Abstract: A method for forming a multi-layer blank of a ceramic material including the steps of: providing a mold that includes at least one side wall surrounding a lower press plunger to form a cavity therebetween, wherein the lower press plunger has a movable pin; filling into the mold a first ceramic material; extending the movable pin from an upper surface of the lower press plunger and into the cavity; pressing a first upper press plunger against the first ceramic material so that a first open cavity is formed while at least a portion of the first upper press plunger is in contact with the movable pin to maintain the through-hole through the first layer; filling into the mold a second ceramic material of a different composition; extending the movable pin from an upper surface of the first layer and into the first open cavity; and pressing a second upper press plunger against the second layer so that a second open cavity is formed in communication with the through-hole that extends through the first and second layeType: ApplicationFiled: February 4, 2022Publication date: August 10, 2023Applicant: DENTSPLY SIRONA INC.Inventors: Stefan FECHER, Lothar VÖLKL, Sven GIESE, Tobias RÖSCH, Andreas GEBHARDT
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Publication number: 20230014589Abstract: The present invention is related to a dental implant comprising at least a lower part and at least an upper part; wherein said lower part of the dental im-plant, which is adapted to be connected to the jawbone of a patient, is made of an at least first material; wherein said upper part of the dental implant, which is adapted to be connected to the lower part of the dental implant, is made of an at least second material; and wherein the upper surface of the upper part of the dental implant is adapted to be aligned with the upper surface of the jawbone of a patient; wherein said at least first material is different from said at least second material; wherein the at least second material of the upper part of the implant is made of a ceramic material, and wherein said ceramic material comprises zirco-nium dioxide comprising at least one coloring additive.Type: ApplicationFiled: December 10, 2020Publication date: January 19, 2023Applicant: DENTSPLY SIRONA Inc.Inventors: Lothar VÖLKL, Stefan FECHER
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Publication number: 20220281770Abstract: The invention relates to a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that in the form body comprising lithium silicate glass or containing lithium silicate glass the lithium ions are replaced by alkali ions of greater diameter to generate a surface compressive stress. To this end the form body is covered with a melt containing an alkali metal for which an aliquoted quantity of salt containing the alkali metal is used.Type: ApplicationFiled: May 23, 2022Publication date: September 8, 2022Applicant: DENTSPLY SIRONA Inc.Inventors: Stefan FECHER, Lothar VÖLKL
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Patent number: 11370702Abstract: The invention relates to a method to derive a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that in the form body comprising lithium silicate glass or containing lithium silicate glass the lithium ions are replaced by alkali ions of greater diameter to generate a surface compressive stress. To this end the form body is covered with a melt containing an alkali metal for which an aliquoted quantity of salt containing the alkali metal is used.Type: GrantFiled: May 20, 2016Date of Patent: June 28, 2022Assignee: DENTSPLY SIRONA INC.Inventors: Stefan Fecher, Lothar Völkl
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Publication number: 20220183804Abstract: The present invention is related to a pink colored pre-sintered or fully-sintered blank for use for the production of a dental restoration, such as a denture base of a full or a partial denture, a partial denture, or an implant supported denture, consisting of a ceramic material which comprises zirconium dioxide doped with yttrium oxide (Y2O3), calcium oxide (CaO), magnesium oxide (MgO) and/or cerium oxide (CeO2), wherein the pink colored blank comprises 2 to 25 wt %, preferably 4 to 17 wt %, and more preferably 5 to 12 wt %, erbium oxide.Type: ApplicationFiled: December 13, 2021Publication date: June 16, 2022Applicant: DENTSPLY SIRONA INC.Inventors: Stefan FECHER, Lothar VÖLKL, Daniel AMMON
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Publication number: 20220184847Abstract: The present invention is related to a method for producing a ceramic multilayer blank comprising at least a first layer of a first ceramic material and at least a second layer of a second ceramic material, wherein the first layer and the second layer are made of ceramic materials of different compositions, which are filled in pourable condition layer-by-layer into a mold and thereafter they are pressed and then sintered, wherein the first layer is a pink colored layer, wherein the first ceramic material comprises 2 to 25 wt % erbium oxide.Type: ApplicationFiled: December 13, 2021Publication date: June 16, 2022Applicant: DENTSPLY SIRONA INC.Inventors: Stefan FECHER, Lothar VÖLKL, Daniel AMMON
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Publication number: 20220175500Abstract: A blank for milling or grinding a dental article, the blank having a plate-shaped body adapted to be received in a blank holder of a CAM system, which plate-shaped body comprises one or more ceramic or glass ceramic blank portions and two or more through holes, wherein each through hole is contiguous with at least one of the ceramic or glass ceramic blank portions for receiving a working end of a milling or grinding tool of the CAM system.Type: ApplicationFiled: March 11, 2020Publication date: June 9, 2022Applicant: DENTSPLY SIRONA Inc.Inventors: Stefan FECHER, Lothar VÖLKL, Markus VOLLMANN, Andreas GEBHARDT
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Patent number: 11166794Abstract: The invention relates to a support body for a blank, whereby the support body possesses a receiving opening for the blank that is surrounded by an inner circumferential surface, which terminates in an upper and a lower edge, and whereby a blank fixed in position within the support body is bonded to the latter by means of an adhesive agent. In order to be able to easily introduce the adhesive agent into a gap between the blank and the support body it is intended that the inner circumferential surface possesses at least one depression and/or elevation extending to accommodate the adhesive agent.Type: GrantFiled: May 10, 2019Date of Patent: November 9, 2021Assignee: DENTSPLY SIRONA INC.Inventors: Martin Kutzner, Stefan Fecher, Lothar Völkl
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Publication number: 20210290351Abstract: The present invention is related to a method for the manufacture of a multilayer blank, having a lowermost layer and a topmost layer, of a ceramic material, where layers of different compositions are introduced layer-by-layer into a mold, compressed and then sintered and where individual layers contain at least one coloring oxide, wherein as a first coloring oxide as the one coloring oxide at least one oxide from the group Co, Mn, Ni, Cr is used, the proportion of which in the lowermost layer containing the first coloring oxide is lower than in the topmost layer containing the first coloring oxide: and at least one oxide from the group Pr, Er, Fe, Ti, V, Bi, Cu, Tb is used as the second coloring oxide, the proportion of which in the lowermost layer containing the second coloring oxide is greater than that in the topmost layer.Type: ApplicationFiled: August 1, 2019Publication date: September 23, 2021Applicant: DENTSPLY SIRONA Inc.Inventors: Lothar VOELKL, Stefan FECHER, Martin KUTZNER, Tanja OEFNER, Christian KOHLER, Tobias KRANZ, Andreas GEBHARDT, Martin HAIZMANN, Heiner HOERHOLD, Andrea BURNS
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Patent number: 11040909Abstract: The invention relates to a method to increase the strength of a form body of lithium silicate glass ceramic, which after it has a desired end geometry and after the application of a material which influences its surface to form a coating, is subject to a heat treatment. To create a surface compressive stress through the replacement of lithium ions by alkali ions of greater diameter at least that region not covered by the application layer is covered by a melt or paste consisting of or containing a salt of an alkali metal with ions of greater diameter and the form body is in contact with the melt or paste for a period of time t at a temperature T and the melt or paste is subsequently removed from the form body.Type: GrantFiled: May 20, 2016Date of Patent: June 22, 2021Assignee: DENTSPLY SIRONA Inc.Inventors: Lothar Völkl, Stefan Fecher
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Publication number: 20190321147Abstract: A method for manufacturing a shaped body, comprising creating a mixture of a metal powder and binding agent, compacting the mixture to form a green compact, heating the green compact to a debinding start temperature T1, debinding the green compact by controlled heating of the green compact from start temperature T1 to end temperature T2 at a heat-up rate R1, presintering the debindered green compact to the presinter end temperature TVS at a heat-up rate RHVS, cooling the green compact from the presinter end temperature TVS at a cool-down rate RKVS, whereby at least the heat-up rate RHVS, the presinter end temperature TVS, and the cool-down rate RKVS are tuned relative to each other in such a way that the presintered green compact forming a blank has a surface porosity of 16% to 22% after presintering, and machining and sintering of the blank to form the shaped body.Type: ApplicationFiled: June 26, 2019Publication date: October 24, 2019Applicant: DEGUDENT GMBHInventors: Jörg HACHENBERG, Rudi STEINKE, Markus VOLLMANN, Irmgard WISSEL, Gerhard ZELLMANN, Elmar HOCK, Stefan FECHER, Lothar VÖLKL
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Publication number: 20190274798Abstract: The invention relates to a support body for a blank, whereby the support body possesses a receiving opening for the blank that is surrounded by an inner circumferential surface, which terminates in an upper and a lower edge, and whereby a blank fixed in position within the support body is bonded to the latter by means of an adhesive agent. In order to be able to easily introduce the adhesive agent into a gap between the blank and the support body it is intended that the inner circumferential surface possesses at least one depression and/or elevation extending to accommodate the adhesive agent.Type: ApplicationFiled: May 10, 2019Publication date: September 12, 2019Applicant: DENTSPLY SIRONA INC.Inventors: Martin Kutzner, Stefan Fecher, Lothar Völkl
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Patent number: 10327874Abstract: The invention relates to a support body for a blank, whereby the support body possesses a receiving opening for the blank that is surrounded by an inner circumferential surface, which terminates in an upper and a lower edge, and whereby a blank fixed in position within the support body is bonded to the latter by means of an adhesive agent. In order to be able to easily introduce the adhesive agent into a gap between the blank and the support body it is intended that the inner circumferential surface possesses at least one depression and/or elevation extending to accommodate the adhesive agent.Type: GrantFiled: January 19, 2016Date of Patent: June 25, 2019Assignee: DENTSPLY SIRONA Inc.Inventors: Martin Kutzner, Stefan Fecher, Lothar Völkl
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Publication number: 20160340237Abstract: The invention relates to a method to derive a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that in the form body comprising lithium silicate glass or containing lithium silicate glass the lithium ions are replaced by alkali ions of greater diameter to generate a surface compressive stress. To this end the form body is covered with a melt containing an alkali metal for which an aliquoted quantity of salt containing the alkali metal is used.Type: ApplicationFiled: May 20, 2016Publication date: November 24, 2016Applicant: DENTSPLY SIRONA Inc.Inventors: Stefan FECHER, Lothar VÖLKL
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Publication number: 20160340238Abstract: The invention relates to a method to increase the strength of a form body of lithium silicate glass ceramic, which after it has a desired end geometry and after the application of a material which influences its surface to form a coating, is subject to a heat treatment. To create a surface compressive stress through the replacement of lithium ions by alkali ions of greater diameter at least that region not covered by the application layer is covered by a melt or paste consisting of or containing a salt of an alkali metal with ions of greater diameter and the form body is in contact with the melt or paste for a period of time t at a temperature T and the melt or paste is subsequently removed from the form body.Type: ApplicationFiled: May 20, 2016Publication date: November 24, 2016Applicant: DENTSPLY SIRONA Inc.Inventors: Lothar VÖLKL, Stefan FECHER
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Publication number: 20160229742Abstract: The invention relates to a method for the production of a medical form body comprising or containing a lithium silicate glass ceramic. To allow the strength of the form body to be increased compared to the prior art, it is proposed that in a preform body comprising or containing a lithium silicate glass ceramic with a geometry that corresponds to the form body a surface compressive stress is created by replacement of lithium ions with alkali ions of greater diameter, wherein after substitution of the ions the preform body is used as the form body.Type: ApplicationFiled: January 29, 2016Publication date: August 11, 2016Inventors: Lothar Wondraczek, Stefan Fecher, Lothar Völkl
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Publication number: 20160206411Abstract: The invention relates to a support body for a blank, whereby the support body possesses a receiving opening for the blank that is surrounded by an inner circumferential surface, which terminates in an upper and a lower edge, and whereby a blank fixed in position within the support body is bonded to the latter by means of an adhesive agent. In order to be able to easily introduce the adhesive agent into a gap between the blank and the support body it is intended that the inner circumferential surface possesses at least one depression and/or elevation extending to accommodate the adhesive agent.Type: ApplicationFiled: January 19, 2016Publication date: July 21, 2016Inventors: Martin Kutzner, Stefan Fecher, Lothar Völkl
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Patent number: 8986009Abstract: A process for determining 3-D data of at least one prepared jaw area, such as a prepared tooth stump, by mechanically scanning the jaw area and digitizing the measured values determined during the scanning. The jaw area is prepared with a dental instrument having positions which are optically measured during the preparation, and the 3-D data is determined from the positions of the dental instrument that are associated with the prepared jaw area.Type: GrantFiled: April 2, 2009Date of Patent: March 24, 2015Assignee: Degudent GmbHInventors: Lothar Völkl, Stefan Fecher, Hartmut Brinkmann, Ralf Jaumann
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Patent number: 8685294Abstract: Method of producing a dental ceramic structure by digitizing a model or partial model of the prosthesis to be produced and generating a CAD data set, cutting each section of the muffle based on the CAD data set to form the cavity, pressing the ceramic into the cavity by way of at least one sprue, removing the hardened ceramic from the cavity with the sprue or flash and removing the sprue or flash based on the CAD data set.Type: GrantFiled: December 17, 2004Date of Patent: April 1, 2014Assignee: Degudent GmbHInventors: Stefan Fecher, Lothar Völkl
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Patent number: 7922489Abstract: The invention relates to a process for determining the form a duplicate of a residual tooth area, which is to be fitted with a dental restoration whereby the duplicate sections to be fitted with the restoration are removed from the duplicate and the form data to be allocated to their forms has to be determined and stored in a computer, by means of which the form of the restoration is calculated taking into consideration the spatial allocation of the duplicate sections. In order to be able to determine the shape of the residual tooth area to be fitted with the restoration, and thereby determine the shape of the restoration itself with high precision, it is proposed that the duplicate sections are or are being individually referenced to each other in their spatial allocation to each other according to a referencing stored in the computer.Type: GrantFiled: December 8, 2004Date of Patent: April 12, 2011Assignee: Degudent GmbHInventors: Lothar Völkl, Philip Von Schroeter