Patents by Inventor Markus Vollmann
Markus Vollmann 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: 20240041574Abstract: The invention relates to a method for the production of a blank of a ceramic material, wherein a first ceramic material and then a second ceramic material of different compositions are filled into a mold and wherein the materials are pressed and after pressing are sintered. Thereby, a layer of the first ceramic material is filled into the mold, a first open cavity is formed in the layer, the second ceramic material is filled into the first open cavity and the materials are pressed together and are then heat-treated. Both the first ceramic material and the second ceramic material contain, or consists of, lithium silicate glass ceramic.Type: ApplicationFiled: October 20, 2023Publication date: February 8, 2024Applicant: DENTSPLY SIRONA Inc.Inventors: Markus VOLLMANN, Lothar VOLKL, Stefan FECHER, Carsten WIESNER
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Patent number: 11833003Abstract: The invention relates to a method for the production of a blank of a ceramic material, wherein a first ceramic material and then a second ceramic material of different compositions are filled into a mold and wherein the materials are pressed and after pressing are sintered. Thereby, a layer of the first ceramic material is filled into the mold, a first open cavity is formed in the layer, the second ceramic material is filled into the first open cavity and the materials are pressed together and are then heat-treated. Both the first ceramic material and the second ceramic material contain, or consists of, lithium silicate glass ceramic.Type: GrantFiled: October 17, 2017Date of Patent: December 5, 2023Assignee: DENTSPLY SIRONA INC.Inventors: Markus Vollmann, Lothar Volkl, Stefan Fecher, Carsten Wiesner
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Publication number: 20230099360Abstract: The invention relates to glass-ceramics based on the lithium silicate system which can be mechanically machined easily in an intermediate step of crystallization and, after complete crystallisation, represent a very strong, highly-translucent and chemically-stable glass-ceramic Likewise, the invention relates to a method for the production of these glass-ceramics. The glass-ceramics according to the invention are used as dental material.Type: ApplicationFiled: June 28, 2022Publication date: March 30, 2023Applicants: FRAUNHOFER-GESELLSCHAFT zur Förderung der angewandten Forschung e.V., VITA Zahnfabrik H. Rauter GmbH & Co. KG, DeguDent GmbHInventors: Bernhard DURSCHANG, Jörn PROBST, Norbert THIEL, Joachim BIBUS, Markus VOLLMANN, Udo SCHUSSER
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Patent number: 11427504Abstract: The invention relates to a method to produce a dental structure with a cavity having a negative form of the structure, which is formed in an investment material, wherein flowable lithium silicate glass ceramic is pressed into the cavity. Thereby a compressive surface stress is created in the ceramic structure through the replacement of lithium ions by alkali ions, in that the model is enriched with alkali compounds and/or the model is covered with a layer of a material containing alkali ions.Type: GrantFiled: May 19, 2016Date of Patent: August 30, 2022Assignee: DENTSPLY SIRONA INC.Inventors: Markus Vollmann, Udo Schusser
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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: 11117829Abstract: The invention relates to a lithium silicate glass ceramic, which contains at least lithium disilicate as a crystal phase, and lithium aluminum silicate as further crystal phase. The lithium silicate glass ceramic in its initial composition contains Al2O3 at 1.5 to 3.5 percent by weight, and K2O at 0.6 to 1.8 percent by weight.Type: GrantFiled: July 31, 2019Date of Patent: September 14, 2021Assignee: DENTSPLY SIRONA Inc.Inventors: Markus Vollmann, Irmgard Wissel, Marcel Meegdes, Carsten Wiesner
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Publication number: 20210177544Abstract: The present invention is related to a dental prosthesis, in particular a crown, consisting of or comprising an inner primary part, such as a cap, which is joined in a fixed manner to an outer secondary part. Further, the present invention is also directed to a dental kit for manufacturing or producing such a dental prosthesis, in particular a crown.Type: ApplicationFiled: July 31, 2019Publication date: June 17, 2021Applicant: DENTSPLY SIRONA Inc.Inventor: Markus VOLLMANN
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Publication number: 20210055157Abstract: The invention relates to glass-ceramics based on the lithium silicate system which can be mechanically machined easily in an intermediate step of crystallisation and, after complete crystallisation, represent a very strong, highly-translucent and chemically-stable glass-ceramic. Likewise, the invention relates to a method for the production of these glass-ceramics. The glass-ceramics according to the invention are used as dental material.Type: ApplicationFiled: September 4, 2020Publication date: February 25, 2021Applicants: FRAUNHOFER-GESELLSCHAFT zur Förderung der angewandten Forschung e.V., VITA Zahnfabrik H. Rauter GmbH & Co. KG, DeguDent GmbHInventors: Bernhard DURSCHANG, Jörn Probst, Norbert Thiel, Joachim Bibus, Markus Vollmann, Udo Schusser
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Publication number: 20200339470Abstract: The invention relates to a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that a surface compressive stress is created in a form body of lithium silicate glass, or containing lithium silicate glass, through the replacement of lithium ions by alkali metal ions of greater diameter. For this purpose the form body is covered with a paste that contains alkali metal.Type: ApplicationFiled: July 13, 2020Publication date: October 29, 2020Applicant: DENTSPLY SIRONA Inc.Inventors: Michael PRÖPSTER, Markus VOLLMANN
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Patent number: 10765496Abstract: The invention relates to glass-ceramics based on the lithium silicate system which can be mechanically machined easily in an intermediate step of crystallisation and, after complete crystallisation, represent a very strong, highly-translucent and chemically-stable glass-ceramic. Likewise, the invention relates to a method for the production of these glass-ceramics. The glass-ceramics according to the invention are used as dental material.Type: GrantFiled: December 20, 2018Date of Patent: September 8, 2020Assignees: FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V., VITA ZAHNFABRIK H. RAUTER GMBH & CO. KG, DEGUNDENT GMBHInventors: Bernhard Durschang, Jörn Probst, Norbert Thiel, Joachim Bibus, Markus Vollmann, Udo Schusser
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Patent number: 10745319Abstract: The invention relates to a method to produce a medical form body of lithium silicate glass ceramic. To increase its strength it is proposed that a surface compressive stress is created in a form body of lithium silicate glass, or containing lithium silicate glass, through the replacement of lithium ions by alkali metal ions of greater diameter. For this purpose the form body is covered with a paste that contains alkali metal.Type: GrantFiled: May 20, 2016Date of Patent: August 18, 2020Assignee: DENTSPLY SIRONA Inc.Inventors: Michael Pröpster, Markus Vollmann
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Patent number: 10537411Abstract: The invention relates to a method for producing a monolithic form body, in particular a dental restoration, comprising the steps of: providing of a blank, producing of the form body through pressing and/or machining of the blank, and softening of the form body exclusively in its surface region by irradiation with infrared radiation.Type: GrantFiled: March 8, 2017Date of Patent: January 21, 2020Assignee: DENTSPLY SIRONA Inc.Inventor: Markus Vollmann
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Patent number: 10531938Abstract: The invention relates to a method for the production of a restoration from a blank consisting of, or containing, a lithium silicate glass ceramic, wherein at least two layers of ceramic material of different compositions are filled into a mold layer-by-layer and after filling of the layers they are then pressed and sintered, wherein after filling of a first layer this is structured on its surface in such a way that the first layer, viewed across its surface, differs in its height from region to region, and then a layer with a composition that differs from the first layer is filled as a second layer into the mold. After sintering the dental restoration is produced from the blank by mechanical working.Type: GrantFiled: October 18, 2017Date of Patent: January 14, 2020Assignee: DENTSPLY SIRONA INC.Inventors: Markus Vollmann, Lothar Volkl, Stefan Fecher, Carsten Wiesner
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Publication number: 20190382304Abstract: The invention relates to a lithium silicate glass ceramic, which contains at least lithium disilicate as a crystal phase, and lithium aluminum silicate as further crystal phase. The lithium silicate glass ceramic in its initial composition contains Al2O3 at 1.5 to 3.5 percent by weight, and K2O at 0.6 to 1.8 percent by weight.Type: ApplicationFiled: July 31, 2019Publication date: December 19, 2019Applicant: DENTSPLY SIRONA Inc.Inventors: Markus VOLLMANN, Irmgard WISSEL, Marcel MEEGDES, Carsten WIESNER
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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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Patent number: 10442725Abstract: The invention relates to glass ceramics based on the lithium metasilicate system (Li2O.SiO2(Li2SiO3)), which are mechanically processible in a simple manner in an intermediate stage of the crystallization and, after complete crystallization, represent a high-strength, highly translucent and chemically stable glass ceramic.Type: GrantFiled: September 4, 2015Date of Patent: October 15, 2019Assignees: FRAUNHOFER-GESELLSCHAFT zur Förderung der angewandten Forschung e.V., VITA Zahnfabrik H. Rauter GmbH & Co. KG, DeguDent GmbHInventors: Bernhard Durschang, Jörn Probst, Norbert Thiel, Michael Gödiker, Markus Vollmann, Udo Schusser
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Patent number: 10407341Abstract: The invention relates to a lithium silicate glass ceramic, which contains at least lithium disilicate as a crystal phase, and lithium aluminum silicate as further crystal phase. The lithium silicate glass ceramic in its initial composition contains Al2O3 at 1.5 to 3.5 percent by weight, and K2O at 0.6 to 1.8 percent by weight.Type: GrantFiled: September 27, 2017Date of Patent: September 10, 2019Assignee: DENTSPLY SIRONA Inc.Inventors: Markus Vollmann, Irmgard Wissel, Marcel Meegdes, Carsten Wiesner
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Patent number: 10357343Abstract: The invention relates to glass-ceramics based on the lithium disilicate system which can be mechanically machined easily in an intermediate step of crystallisation and, after complete crystallisation, represent a very strong, highly-translucent and chemically-stable glass-ceramic. Likewise, the invention relates to a method for the production of these glass-ceramics. The glass-ceramics according to the invention are used as dental material.Type: GrantFiled: January 9, 2017Date of Patent: July 23, 2019Assignees: Vita Zahnfabrik H. Rauter GmbH & Co. KG, DeguDent GmbHInventors: Bernhard Durschang, Jörn Probst, Norbert Thiel, Joachim Bibus, Markus Vollmann, Udo Schusser
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Publication number: 20190142556Abstract: The invention relates to glass-ceramics based on the lithium silicate system which can be mechanically machined easily in an intermediate step of crystallisation and, after complete crystallisation, represent a very strong, highly-translucent and chemically-stable glass-ceramic. Likewise, the invention relates to a method for the production of these glass-ceramics. The glass-ceramics according to the invention are used as dental material.Type: ApplicationFiled: December 20, 2018Publication date: May 16, 2019Applicants: FRAUNHOFER-GESELLSCHAFT zur Förderung der angewandten Forschung e.V., VITA Zahnfabrik H. Rauter GmbH & Co. KG, DeguDent GmbHInventors: Bernhard DURSCHANG, Jörn PROBST, Norbert THIEL, Joachim BIBUS, Markus VOLLMANN, Udo SCHUSSER
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Publication number: 20190099244Abstract: The invention relates to a method for the production of a blank of a ceramic material, wherein a first ceramic material and then a second ceramic material of different compositions are filled into a mold and wherein the materials are pressed and after pressing are sintered. Thereby, a layer of the first ceramic material is filled into the mold, a first open cavity is formed in the layer, the second ceramic material is filled into the first open cavity and the materials are pressed together and are then heat-treated. Both the first ceramic material and the second ceramic material contain, or consists of, lithium silicate glass ceramic.Type: ApplicationFiled: October 17, 2017Publication date: April 4, 2019Applicant: DENTSPLY SIRONA Inc.Inventors: Markus VOLLMANN, Lothar VOLKL, Stefan FECHER, Carsten WIESNER